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Category: Electric Ferry

  • Want Electric Ships? Build a Better Battery

    Want Electric Ships? Build a Better Battery

    Large container ships are a major contributor to greenhouse gas emissions, but electrifying the world’s fleet faces steep technological hurdles.

    Published in WIRED Magazine, By Daniel Oberhaus, March 19, 2020 https://www.wired.com/story/want-electric-ships-build-a-better-battery/

    LATER THIS YEAR, the world’s largest all-electric container ship is expected to take its maiden voyage, setting sail from a port in Norway and traveling down the Scandanavian coast. Known as the Yara Birkeland, the ship was commissioned by Yara, a Norwegian fertilizer company, to move its product around the country. The company expects the ship to reduce carbon emissions by eliminating about 40,000 trips each year that would otherwise be made by diesel-powered trucks.

    There are about 50,000 cargo ships operating around the world, and each year their engines spew about 900 million metric tons of CO2 and other pollutants into the atmosphere. Indeed, the 15 largest container ships alone emit more nitrogen oxide and sulphur oxide pollutants than all the world’s cars combined. Electrifying cars and other modes of transport promises to significantly reduce greenhouse gas emissions, and the same is true of the shipping sector.

    Yara Birkeland illustration showing it being docked
    An illustration of the Yara Birkeland, which will transport cargo in Norway using battery power.

    COURTESY OF YARA INTERNATIONAL ASA

    But conventional lithium-ion batteries can only pack enough power to move small ships like the Yara Birkeland over short distances. If we want to electrify the world’s largest cargo ships, we’re going to need some better batteries.

    Building battery-powered ships comes with two big problems. The first is that conventional lithium-ion batteries pose safety risks, because they use liquid electrolytes to carry lithium ions between the electrodes. If the components in a battery degrade, this can cause the cell to rapidly heat up and fail, a process known as thermal runaway. The battery’s heat can lead to a cascade of failures in nearby batteries. If these batteries release their chemicals as they fail, all it takes is one battery to catch on fire and cause a large explosion. That would be bad anywhere, but it’s particularly bad at sea where there are millions of dollars of cargo on the line and limited escape routes for crew.

    Last year, a small fire in the battery room of a hybrid-electric ferry in Norway resulted in an explosion. The ferry operator was able to evacuate passengers and crew to land before the explosion, but a similar event on a cargo ship in the middle of the ocean could be catastrophic.

    SPBES, a Canadian energy-technology company, is working to reduce the risk of electric vessels by designing marine energy systems that are resistant to thermal runaway. The company’s energy system, which is currently installed on roughly 20 ferries and tugboats around the world, uses lithium nickel manganese cobalt, or NMC, batteries. This is the same conventional lithium-ion chemistry you’ll find in most consumer electronics or electric vehicles, which have had their fair share of thermal runaway problems.

    a man in a control room
    COURTESY OF FORSEA

    To lower the risk of explosions on boats, SPBES built a battery container with a liquid cooling system that wicks away thermal energy faster than a battery in meltdown can produce it. While this won’t prevent a battery from failing, it does prevent the kinds of cascading failures that lead to explosions, says Grant Brown, cofounder and vice president of marketing at SPBES. “Our technology is basically bomb-proof,” says Brown. “It’s really tough stuff.”

    SPBES also designed its energy system to make it easy to swap out individual cells if they fail or reach the end of their lifetime. This helps address what may become a bane of the electric shipping industry: handling battery waste. Cargo ships will require hundreds of thousands of batteries, so the ability to selectively remove individual cells rather than scrapping the entire energy system will be critical to reducing waste. “Why throw away so much perfectly good material when you can simply reuse most of it?” asks Brown. “In terms of environmental impact, this is the future.”

    A second major challenge facing electric ships is that conventional lithium-ion battery chemistries simply don’t pack enough power to move cargo around the world. Today, batteries based on NMC chemistries can only be used to electrify ferries and small container ships like the Yara Birkeland. Yara’s ship is powered by enough batteries to provide up to 9 megawatt-hours of energy. It’s the equivalent of 90 Tesla Model S battery packs, and enough for short trips of up to 30 nautical miles while carrying 3,200 tons of cargo.

    But to meet the energy demands of massive international cargo ships, which carry tens of thousands of tons of cargo and use dozens of gigawatt-hours of energy, we’re going to need more advanced batteries. “Cargo ship engines can be as tall as a four-story house and as wide as three buses,” says Natasha Brown, a spokesperson for the UN International Maritime Organization. “At present, the size of the battery needed would likely limit the amount of cargo that could be carried, making it commercially nonviable.”

    To meet the energy needs of the next generation of electrified boats, Washington-based energy-technology company Lavle is developing an advanced energy-storage system based on solid electrolyte batteries. Lavle’s cells are made by 3DOM, a Japanese battery manufacturer that created a new type of separator made from a porous resin that is stacked between the layers of solid electrolyte material that carry ions between the battery’s electrodes. Swapping out liquid electrolytes for solid electrolytes reduces the risk of thermal runaway. Adding in the new separator increases the battery’s performance by efficiently transporting lithium ions.

    battery render showing patented CellCool system.
    COURTESY OF SPBES

    “From an energy density standpoint, we’re approaching three times what standard lithium-ion batteries on the market can do,” says Lavle CEO Jason Nye. But Nye sees Lavle’s solid electrolyte batteries as just a step on the road to an even better type of power pouch known as a lithium metal battery, which uses an anode made from solid lithium metal rather than a more typical carbon anode. Nye says its lithium metal anode can push the cell’s energy density even higher and would be easier to mass produce than a solid electrolyte battery.

    Ben Gully, Lavle’s chief technical officer, describes this kind of cell as a “holy grail” in energy storage development. Lithium metal batteries can boost a cell’s energy density and charging rates because the lithium metal anode easily gives up its ions. But the lithium anode swells a lot while a battery is charging, which can cause it to decouple from the electrolyte. Furthermore, lithium metal is highly reactive with most available electrolytes, and this causes them to degrade.

    Gully says Lavle and 3DOM were able to overcome these issues by using its new separator technology and making other tweaks to the lithium metal battery chemistry. Gully wouldn’t go into the details of the company’s “secret sauce” for making lithium metal batteries, but he says the company’s experimental lithium metal cells have already demonstrated a threefold improvement in energy density compared with conventional lithium-ion batteries.

    a boat
    COURTESY OF FORSEA

    Considering that the efficiency of rechargeable lithium-ion cells has only tripled since they were commercialized 30 years ago, Lavle’s batteries are showing the sort of large performance increase that is needed to electrify the world’s shipping fleet. For now, these batteries remain experimental, and the company still needs to demonstrate that they can be used in a commercial vessel. Lavle expects to begin deploying prototypes of its advanced energy systems in smaller vessels like ferries by the middle of next year, but Nye says that in the future their system could scale to meet the needs of large cargo ships.

    Even with these new advancements in marine energy-storage systems, cargo ships may never be able to rely on battery systems alone. Agis Koumentakos, a Greek energy trader and coauthor of a recent paper on electric ships, cites several environmental and geopolitical challenges that come with the electrification of the maritime sector.

    On the environmental side, each cargo ship will require dozens of tons of batteries that have limited shelf lives. The recycling industry isn’t ready to handle the surge in depleted lithium-ion cells, which come with several storage and handling challenges. Electrifying cargo ships could significantly accelerate the problem. On the geopolitical side, batteries require a lot of mined material, some of which is sourced from mines that employ child labor. Even if these materials can be sourced ethically, China controls a lot of the supply chain for lithium-ion batteries, and Koumentakos says policymakers may be wary of becoming totally dependent on China for maritime cargo transport.

    But using batteries for cargo ships isn’t an all-or-nothing proposition. Instead, they may be combined with other clean forms of energy generation, such as hydrogen fuel cells, solar, or even wind. “Batteries probably won’t be a monopoly in ship propulsion,” says Koumentakos. “It’s going to be a mixture of technologies.”

    Solar energy has been used on cargo ships for years to partially meet their electricity needs, but photovoltaic tech will never be energy-dense enough to power a ship on its own, Koumentakos says. Another option is to return to the original source of ship propulsion—the wind—using technologies like large metal sails or rotor sails to propel large cargo ships and reduce energy costs. And if the fabled hydrogen economy emerges in the coming decades, ships could implement hydrogen fuel cells as a primary source of propulsion and use batteries as backups.

    The development of high-performance energy-storage systems for ships may also see wide application beyond the maritime sector. Nye says Lavle’s technology could also be a good fit for electric aircraft like the vertical-takeoff-and-landing vehicles currently under development as air taxis, and Brown says SPBES is exploring large-scale applications for its energy system on land.

    The maiden voyage of the Yara Birkeland later this year will be a small but important milestone toward electrifying the world’s ships. As one of the only fully electric cargo ships in the world, it will show what’s possible with today’s technology and serve as a blueprint for the electrified ships of the future.

  • Determining Value in Energy Storage

    Determining Value in Energy Storage

    Comparing total cost of ownership against bare cost of batteries

    MarineLink March 15, 2020 https://www.marinelink.com/sponsored/pressrelease/determining-value-in-energy-storage-100383

    Introduction
    In the 10 years since I started the first company dedicated to producing specialist lithium ion batteries for the marine industry, there has been a huge uptake from the market. In the very early days, I would tell people that their vessels would be able to run on battery power and they would look at me with disbelief; at that point in time, land based electric propulsion was rare and – in many cases – people’s experiences of it painted a picture of inconsistency and unreliability.

    Fast forward and the electric cars are here to stay. With few exceptions, western countries are committing to exclusively use electric or hybrid electric vehicles in the medium term. Lithium battery power taken hold in other industries in a similar way, especially commercial shipping. Commercial mariners the world over have fully embraced the use of the technology. They are cheaper and cleaner to run and, most importantly, they outperform conventional vessels with very short-term payback.

    Today, most vessels being built either use energy storage in some way or have the provision for it. They are being built to future proof their investment.

    The Apples to Apples comparison
    At the beginning of the age of megawatt scale lithium energy systems, it was determined that cost per kilowatt hour (kWh) was a good way to measure the value that lithium could be evaluated. In the years since, there have been many articles, white papers, and countless conference speeches about the goal of reducing the cost of lithium batteries to below $100 USD/kWh. This may be an arbitrary number largely driven by the stationary grid and automotive suppliers, but suppliers were trying to use this measure to identify when lithium would be cheap enough for these industries to be successful.

    The problem with using an arbitrary metric like cost/kWh is that it assumes that all lithium batteries are equal. In the commercial marine space, that assumption is simply not true. The concept of cost/kWh is further complicated by the engineering requirements of marine systems, driven by the flag authorities and classification societies.  Things like safety, reliability and risk a far greater real-world influence on the cost of building batteries for the marine industry and all of the associated systems involved. But, how do we create an “apples for apples” comparison that supports rational commercial decision making?

    The Challenge:
    Power systems on large vessels are highly complex and it is not easy.  At Sterling PBES, we have taken the decision to measure the cost of an installation and its payback by including all of the elements necessary to offer a complete installed system. Batteries (priced per kWh) are a part of this – but certainly not all of it.  For customers to make a sound decision and understand the overall financial impact, everything needs to be considered.

    How do available batteries differ?
    There are several versions of battery chemistry available to the battery manufacturers; the dominant chemistries are NMC, Titanate, and LPO or Iron phosphate.  Each of these chemistries have different energy densities (energy density is the amount of energy stored for the volume of the cell. Systems with lower energy density tend to be heavier as well as larger while higher energy density systems are usually lighter). Different battery systems have different lifecycle characteristics, age in different ways, and charge/discharge characteristics.  The marine industry has gravitated towards NMC as a dominant chemistry but even in one chemistry type there are variations in performance existing from one cell manufacturer to the other, principally focussed on whether the cell is a power cell (instant power) or an energy cell (a larger gas tank).  Even the form factor of the cells has a lot to do with the managed risk and performance of a battery.

    Balance of System
    Then there is the balance of systems required to make a battery system qualify for Type Approval.  These are items from simple things like power cables, communication cables, plumbing systems, racking, emergency ventilation, HVAC, chillers, approved battery rooms, vibration and impact supports, fire detection, fire management, gas detection, and gas management.  While not typically supplied by the battery manufacturer, the impact to each required sub-system to overall system cost can add up: building a complete battery system in this way leads to hidden incremental costs.

    System Integration
    A battery that is not fully integrated is not practical .  We need to ensure that batteries are optimized to their performance characteristics to deliver the best overall return on investment and optimization of risk management. This is typically associated with the systems needed to make the batteries work – switch panels, cooling systems, heat extraction systems, large scale power electronics including inverters, converters, transformers, frequency regulation equipment, integrated power management systems and the sophisticated software that brings it all together to make the whole system work as designed.

    Obviously, integration is a real challenge, but it is imperative that the customers are able to navigate through the many options to actually compare the solutions available and understand the impact to their vessels and their profitability.

    It’s time for a reset in the marine energy storage sector. Batteries make financial sense – that is understood. But when comparing battery systems there is a lack of understanding of the all-in cost of a system. Installed and commissioned system costs may be significantly different than the cost per kWh quoted by some companies. Take liquid cooling for example; a liquid cooling system eliminates the need for expensive HVAC systems and makes a battery able to work at a much higher rate. This results in a far smaller battery not only in terms of installed kWh, but also in physical size and weight. A liquid cooled system doesn’t require large air gaps between components, ducting, or the blowers and compressors for HVAC and costs less overall. Far better value per kWh.

    If you add up all of the costs associated with batteries, you end up with an “apples for apples” comparison: price, performance, weight, volume, risk, and safety.  It is possible to define value by each of the variables and then put it together in a visual way that measures both capex and opex value over the life of a system.

    The concept of value per kWh may be easily demonstrated using a recently developed calculating tool. In this case we will examine the value of a liquid cooled SPBES battery using CellSwap compared to an air-cooled single use battery from a respected competitor. The graph below easily demonstrates the value of a system overall; this graph represents a single example of a system and is relative to a specific project. All systems will have slightly different payback and costs associated with each one.

    The vessel, a hybrid format harbour tug, is a 70-ton bollard pull boat with a battery capacity of approximately 840kWh of Power batteries. In the example below, we see that given a smaller battery size with the associated racking, liquid cooling, and cables, the system costs are lower for the Sterling PBES systems – even including the CellSwap at every 5 years (generally we expect a 5-7 year lifespan from a 5 year warranty battery). The Sterling PBES 10-year system is a strong second option, although can be more expensive in both the short-term and over 30 years.

    The competition was cheaper by the kWh but more expensive as a system. In this case, the air-cooled system cost less per kWh, but lost for a variety of hidden extra costs. It must be larger to achieve the same results, does not include racking, cabling, HVAC, etc. Even with very conservative estimates on additional costs, the air-cooled system loses much quicker. It weighs more, takes up more space, costs more, and may be subject to warranty dispute should the vendor deem that HVAC was not adequate and the system ages faster than anticipated.


    Caption: Calculating value from reviewing all sources and costs.
    Source: Sterling PBES

    Lifetime performance
    What if the battery starts to prematurely fail?

    Most agreements are written with success in mind, but who pays if the battery starts to show premature aging or worse? Sterling PBES offers our customers a Lifetime Performance Agreement (LPA) to ensure fixed and manageable costs associated with its solution. Other battery manufacturers may or may not do the same, but it is a point that needs to be clearly understood. Even recycling needs to be costed into the system; our movement to a more responsible and accountable industry requires us to know what happens at end of life.  Batteries thrown into a landfill is not acceptable – we need to support this phase of system life as thoroughly as the engineering and manufacturing at the start of life.

    The educated purchaser
    When a battery company starts talking about price per kWh as the metric for value, you should be cautious. As shown in this article, there are many additional costs and risks that may not be being addressed in their bid or their program. Here is a list of questions that the educated purchaser should ask of their battery vendor or simply take into account in total system costing:

    System per MWh Sterling PBES Competitor 1 Competitor 2
    Cost per kWh
    Racking included
    Cables- Power included
    Cables- Communications included
    BMS included
    Plumbing included
    Fire Detection included
    Gas Detection $3,000
    Fire Prevention/Suppression included
    Gas Extraction – Emergency included
    Room Ventilation included
    A60 Battery Room shipyard
    HVAC N/A
    Chiller $20,000
    Ventilation $5,000
    Power Electronics $0
    System Integration $0
    Cell Swap $0
    100% Replacement Warranty 2 years
    Lifetime 100% Replacement
    Warranty Available    		 Yes
    Lifetime Software Updates Yes
    Service Reports Yes

    30-year batteries
    Most commercial vessels built today have a lifespan of around 30 years, but the propulsion equipment onboard will require maintenance or rebuild several times. In fact, a vessel may require several rebuilds of machinery over its lifespan, yet most current battery technology only allows for full replacement.

    On this hypothetical 30-year vessel, there will be anywhere from 3-6 battery replacements and subsequent electronic waste entering the recycling stream. Anything that can be done to reduce the environmental impact of the battery should be done.

    This happens against the backdrop of increased regulation on the disposal of lithium ion batteries, especially in the EU, which will undoubtedly impact costs for the supplier and subsequently the end user. Sterling PBES’ proprietary CellSwap technology allows the battery to be rebuilt with new cells as required, usually on a 5-year cycle. This allows for a far more accurate prediction of lifespan and required system size as the battery doesn’t need to be oversized to compensate for variables like changes in route, duty, heat or even ownership and maintenance intervals. In fact, a battery that is designed for a 5-year lifespan with CellSwap may be only 30-50% the size of a battery designed for a 10-year life. If that hypothetical 10-year battery is air-cooled, then the size of an alternative liquid cooled system with CellSwap is even smaller. This, in turn, increases value again for the customer.

    Conclusion
    Battery Installations are complicated, but worth it. The impact to the bottom line, the improvement of the risk profile for a vessel, and the environmental impact all contribute so strongly to the bottom line that it is worth the effort of understanding the total system cost.
    Take comfort in your relationship with all of your partners. We all want your vessels to be successful and work reliably for a very long time, just don’t be fooled by metrics that don’t measure the risk or the impact thoroughly.

    Cheap is not always less expensive, but a value-added decision is critical in a value-added business. ESS is becoming mainstream but currently only 0.5% of the existing global marine fleet currently use ESS – there is huge opportunity for fleet owners to save money and reduce environmental impact of their operations.

    Now that ESS has demonstrated over many years the commercial and environmental benefits within the marine sector it is imperative that we optimize the system size, performance and safety to achieve the best financial returns for our end customers and provide the greatest value.

  • Advances in Battery Safety and Technology

    Advances in Battery Safety and Technology

    Energy storage safety for commercial vessels; lessons learned in practical application

    By Brent Perry, CEO, SPBES

    Published in G Captain on February 3, 2020. https://gcaptain.com/advances-in-battery-safety-and-technology/

    Forward

    A Li-ion battery has several potential hazards that must be considered in order to keep people and equipment safe. It is important to consider these hazards for each stage of the battery life, not just the day it is installed. From manufacturing through to delivery, installation, commissioning, maintenance and eventually the recycling of the battery, safety must be first and foremost.

    At the core of the system is the lithium-ion cell; a chemical power plant that cannot be simply switched off in order to make it safe. A battery cell is by its nature always live; therefore, it is important to ensure the safety of personnel from this potential hazard. The voltage on a single cell is low and therefore not hazardous, however the potential current is very high since the internal resistance of the cell is low. Shorting the positive and negative with a metal object will either result in the battery terminals evaporating or the metal object getting very hot.

    During manufacturing, special tooling and processes are used to decrease the risk of short circuit of a cell. When the cells are assembled in series to form higher voltages collectively in a module, the voltage becomes more dangerous. Again, special assembly tooling is used to protect personnel against accidental shorting. Once assembled it is important to protect personnel from this voltage during transportation, installation, commissioning and de-commissioning.

    For this, SPBES uses a contactor inside the module to isolate the battery voltage from the battery terminals. This contactor can only be closed by the Battery Management System (BMS) during operation, therefore eliminating all voltage related hazards when it is not in use. The total battery voltage once installed is very dangerous considering we commonly install batteries at bus voltages higher than 700VDC and up to 1500VDC. The protection for this is done through proper isolation design, the use of breakers and independent safety circuits like high voltage interlocks, independent breaker trips and ground fault detection.

    The system is also designed to reduce the voltage anywhere on the installation to less than 100V when the system is off. This ensures that any unintentional shorts will not result in a dangerously high current and potential damage to the system.

    Thermal runaway is a potentially catastrophic hazard that must also be in the front of an engineer’s mind when designing a lithium-ion battery. It is rare that thermal runaway occurs, but the impact can be devastating when it does . Our design philosophy is to eliminate the risk completely through our patented cooling system, CellCoolTM.

    Rather than trying to manage the potential consequences of a thermal runaway event, SPBES has always focused on removing this hazard completely.  Even if the cell heats up, regardless of the reason, SPBES’ system can remove the heat quick enough to prevent thermal runaway from occurring. Additionally, SPBES’s cooling system protects the cells from external heat sources such as a fire outside the battery.

    Our philosophy has always been and always will be to protect the vessel and crew to the best of our ability, incorporating new safety innovations from our R&D team as they become available.

    ForSea Aurora travels from Denmark to Sweden using EV battery Propulsion

    Advances in Battery Safety and Technology

    Battery technology has evolved very quickly, but hybrid and electric marine propulsion is still a relatively young industry.  As of today, there are still no commercial systems that can claim to have been in operation for 10 years.  Despite this, the economic and environmental advantages of battery storage have meant that there are now dozens of ships operating in hybrid and full electric modes. By recent estimates, Energy Storage Systems (ESS) are now being incorporated in roughly 75% of refits and new build vessels around the world.

    In 2009 I designed my first lithium batteries for marine applications.  These were designed to demonstrate the principal that MW scale ESS could work like traditional propulsion while delivering real commercial value; and there were a lot of doubters.  Today, we have evolved not only performance, but safety, integration, cost and risk management to much more predictable levels.  The data obtained from constant commercial use of the battery system provided invaluable information that allowed us to evolve and continuously improve our systems.

    The Classification Societies and Flag Authorities have also constantly pushed for better and better systems.  These agencies have been incorporating powerful risk evaluation tools to ensure operator and passenger safety as system capacities got bigger and bigger.

    Operational data and experience have led to significant improvements in battery design resulting in improved safety, system life, risk reduction and overall performance. The improved performance of modern marine batteries have also changed the market. Lower system cost means more and more marine verticals are now finding ROI from energy storage. For example, during the formation of the marine ESS industry, tugboats and ferries represented the best commercial applications for energy storage systems. Today we can add cruise ships, oil and gas, offshore and wind farms vessels to a never-growing list of commercial vessels that are making an ever-greater use of energy storage.

    The key considerations of effective battery design start with two principal issues 1) an ESS must be an improvement to the existing methods of operating ships, and 2) the solution has to deliver financial benefits without external support (government grants or tax credit schemes) in order to permanently earn its place as a part of system design.

    These are the key questions that we asked when at the design table for our current systems, understanding that they are the key to success. However, we also knew from years of real-world experience that the following criteria are also critically important to long term commercial success:

    Safety: we had to be able to effectively eliminate the possibility of thermal runaway in a battery system, otherwise we will never see true acceptability in the markets and growth in system size.  This challenge was at the top of our minds in every design decision, and we addressed it by creating our patented CellCoolTM cooling system that effectively removes the risk of thermal runaway.

    The principal is very simple; reduce the temperature of the cells at a faster rate than the cell increases in temperature. No matter how hard you work them, with CellCoolTM they will not achieve the temperature required to go into thermal runaway.  We worked in cooperation with Classification Societies and Flag Authorities to developed what we all felt were difficult to pass safety tests designed to demonstrate that batteries are inherently safe.  We took this to another level and set our own gold standard as safety in the face of spontaneous combustion- the most difficult test that a battery can face.

    Even in this very demanding test, we have proven success. Our systems are able to prevent significant damage to the battery (including propagation at the cell level) and ultimately make every system safe to operate.  This is done with an inherently simple liquid cooling system.  It cannot be achieved with air cooling systems due to the issue of managing transfer of heat with something as energy dense as most lithium chemistries.

    Waxholmsbolaget Yxlan Ice-class hybrid passenger ferry provides year-round travel in the Stockholm Archipelago.

    Safety has other considerations as well; there is disaster safety at the cell level, and then there is safe use of batteries. We designed a BMS that is inherently focussed on protecting the ship, the battery system and the cells.  This is done at its core by monitoring the voltage and temperature of every individual cell in the system, and then balancing the performance of the vessel within the safe operating principals of the ship.

    There are two different ways to design a BMS; one that is ideal for a fully electric ship and one that suits hybrid applications.  While both in principal will give the operators choices in the event of a battery failure, in a fully electric ship, the safe operation of the vessel becomes the guiding principal of the decision making of the BMS and Power Management System (PMS). In a hybrid application, the batteries can become the focus of the performance of the PMS as the vessel has alternative propulsion systems and is not totally reliant on the battery for operation.  Once we define the type of application as either hybrid or electric, we can optimize the operational logic of the BMS as it pertains to the PMS/operator decision making criteria.

    Another critical element of safety in design has been the inclusion of contactors in our building block modules.  Basically, as we are building DC voltage systems that range from 300-1500VDC, the risk of personal injury in transportation and service are very high. For example, a 1500 VDC arc flash can permanently disable a technician.  By adding contactors in the individual battery modules, we eliminate voltage at the terminals until the system is fully engaged and the BMS can approve that all cables are correctly sequenced and protected.  There is no voltage or power on the terminals as long as they are open.  We also reduce the risk by isolating the building blocks as single units no matter how large the overall size.  The element of crew safety of our technicians and the operators of the vessels cannot be overstated in terms of benefit to our customers. We can now train ships engineers and crew to do maintenance on the batteries, we don’t need to bring in specially qualified electricians to do basic maintenance.  This design decision was not free, but it is the right way to go to improve overall safety for our customers ships.

    SPBES patented eVent system showing path of gas extraction in a single cell thermal event.

    Cost: Another critical part of the design of a battery is not the actual battery itself, but the space the battery operates in. The impact of incremental costs of necessary added systems required for safe operations is significant. In most cases, and in our earlier designs, things like fire safety, fire detection, gas detection, gas extraction, cooling and emergency ventilation were left to other contractors and not included in the cost of the battery system.  These so-called add-on systems are actually critical to the performance of a battery and are not optional, but in most cases battery suppliers will leave these added costs to the ships builders.

    Our approach became more holistic and covered all parts of the battery system as our design evolved, which means less added cost per kWh and more integrated engineering.  Our next evolution in development is to validate the design of our core modules to withstand an A60 battery test. Validation of this test will eliminate the need to build an A60 enclosure for the batteries.

    To put this in context, one of our integrator partners determined that the typical added cost of a battery system could be as high as $275/kWh for a total battery installation, this cost comes on top of the cost of the batteries themselves.

    It is essential that integrators and end customers always understand the overall system costs to allow decisions to be made on return on investment based on the actual installed system costs not just the battery cost.  In fact, SPBES is not completely immune to this cost; our liquid cooling requires chillers sized to meet the power demand of the system and our gas extraction system must be correctly vented, but instead of $275/kWh, we face a cost typically of $20/kWh for the added components and to meet all performance requirements.

    Another benefit of SPBES CellCool liquid cooling is the ability to actually predict the life of our systems. Air cooled systems are very dependent on the ambient battery room temperature to be able to manage the overall life of a lithium battery, and they are very fickle. Even a small increase in ambient battery room temperature will affect the temperature of the lithium cells andcan have a significant reduction in calendar life.  In contrast, liquid cooling maintains the temperature of the cells at a fixed range and we can eliminate the impact of ambient temperature on the performance life of the cells.

    As system life continues to be in the 10-year range and with many operators seeking longer-life solutions, eliminating temperature as a variable goes a long way to meeting lifespan requirements.  There are still a large number of factors that will influence battery life, but temperature is by far the most impactful.

    SPBES 1MWh battery located inside a 20 foot ISO shipping container.

    System Size: Another area where we have seen a significant evolution both in the use of cells and the design of a battery is size. Cell manufacturers have significantly improved energy density over the last ten years. By increasing the energy density of the lithium-ion cells, a significantly smaller system can be created. For example, a system with 88kWh per module versus a battery that has 65kWh per module has already achieved 35%improvement of weight and space required for an installation.  As long as the cycle life meets the lifetime need, this is a huge improvement. In my experience, increases in energy density tend to a reduced cycle life.

    The other significant feature of any system is the percentage of energy available on a continuous basis. On our first-generation air-cooled design, the continuous rating was about 70%. This meant that if we needed 1MW of energy, we needed to have about 1.4MWh of capacity to operate at 1MW load. This meant a larger, heavier system that was also significantly more costly to install and maintain.  If we assumed that the battery system cost $100/kWh, then a 1.4MWh battery would add $140,000 to the capital cost of the system – and does not even consider the ongoing performance and financial impacts of the increased size, weight and maintenance!

    A liquid cooling system allows SPBES to use significantly more of the battery capacity. This really means we can greatly reduce the size and the associated costs of the battery. In our case, the battery can now operate at an average continuous rate (charge and discharge) of 300%.  In the example above, a 1MWh system can now be met with a 350kWh battery; much smaller, much lighter, and much less costly to install, with only a $35,000 budget needed (if the necessary costs were $100/kWh).

    Advanced technology: SPBES’ patented CellCoolTM liquid cooling system reduces risk and increases lifespan.

    While the above model is not always accurate, it is more reflective in what we call power systems.  In energy systems where a slower, more steady output of energy is required, size is totally dependent on capacity.  Clients and operators will understand the concept that their vessels are operating underpower or energy requirements and where energy is the driver, we have engineered a battery system where we can simply use the same battery with all of the same components, but with cells that have higher energy density- so we can significantly reduce the footprint of the battery system.

    Sustainability: A battery that can last for ten years is a pretty amazing thing, but it will never match the lifespan of the vessel itself. This equates to significant costs to replace a battery system every five or ten years on a vessel that will be in service for up to 50 years.  We took this challenge, and in analyzing a system, realized that while all components will require some maintenance, the most significant reason for ESS replacement was the fact the cells will age.

    The answer to continuous replacement (and the capital costs associated with it) is a design that allows us to remove and renew the cells regularly, i.e. every 5 to 10 years.  If we can keep the bulk of the infrastructure and safety systems in place, then we can reduce the cost of replacing the system to the cost of cell replacement and cell recycling. This radically reduces the total cost of operating an electric or hybrid vessel over its lifetime.

    Cell SwapTM has been at the core of our design since 2015, with every module core (regardless of chemistry of the cells) able to be replaced within 30 minutes.  SPBES technicians can perform CellSwap refurbishment while the ship is running or in for maintenance.  Cell swap means that the battery system life span is now the same as that of the vessel; it is similar to engine maintenance and rebuilds.  With this inclusion, the design of the battery system is now in line with marine market requirements.

    Recycling will have an increasingly prominent role in decision making over the next generation. This is part of the benefit of a cell swap; we can safely support the recycling of the lithium cells and do this at a very low cost and impact of operational budgets.  Part of our contracting now is to include end of life recycling with every system. While often overlooked, it is necessary for any company that uses ESS in commercial operations to include this operational expenditure in their impact analysis of utilizing energy storage systems in day to day application.

    Where to next?  I think that commercial needs are going to continue to drive improvements. Natural evolution of clean maritime propulsion with products such as fuel cells will significantly improve environmental impact and cost-effective operations.  Organizations like the IMO and Class and Flag Authorities will continue to motivate us to move the technology forward in order to meet the needs not only of our industry, but those of society as well. We look forward to the challenges of the future and the next generation of developments to come.

  • Gov. Inslee helps launch Washington’s first maritime startup accelerator in Seattle

    Gov. Inslee helps launch Washington’s first maritime startup accelerator in Seattle

    Excerpt from GeekWire, published January 22, 2020.   

    Written by

    The maritime industry has long been an anchor to Washington’s economy. Government and business leaders want to make sure that continues, especially with climate change and sustainability concerns looming.

    That’s the ethos behind the state’s first maritime startup accelerator, which officially launched Tuesday evening at the Port of Seattle headquarters.

    Gov. Jay Inslee spoke at the event. The maritime industry runs deep in the governor’s family; his grandfather was a salmon fisherman in Seattle.

    “I could not be more excited about this because it’s an extension of the basic value system of the state of Washington,” Inslee said, pointing to other local innovation across industries such as retail, gaming, life sciences, and agriculture.

    The Port teamed up with WeWork Labs — WeWork’s startup incubator — and Washington Department of Commerce’s Maritime Blue initiative to create the 4-month program. There are 11 companies in the inaugural cohort, ranging from a healthcare provider for mariners to a whitefish jerky maker.

    The startups will work out of WeWork Labs’ Seattle location and get access to mentors and advisers. WeWork will facilitate seminars and workshops to help the companies navigate challenges and obstacles.

    Accelerators are common in the tech world, but rare in centuries-old industries such as maritime.

    WeWork said the maritime industry in Washington state employs 146,000 people with an economic value of $30 billion. However, a lack of capital both in the Pacific Northwest and worldwide restricts innovation.

    “We knew from our conversations around the globe that there are entrepreneurs and investors ready to take advantage of the blue economy as it’s growing exponentially in this next decade,” said Joshua Berger, Maritime Sector Lead for Gov. Inslee and board chair for Washington Maritime Blue.

    Inslee, the self-declared climate change presidential candidate who exited the race in August, said the accelerator is part of a “larger endeavor we have in the state of Washington.” He noted plans to create the word’s largest hybrid-powered, auto-carrying ferries as one example of reducing emissions and becoming more energy efficient.

    “So while we’re cleaning up the maritime industry, we think it’s the right thing to do to clean up terrestrial pollution as well,” Inslee said.

    SPBES (Vancouver, B.C.)

    “SPBES provides high power lithium ion energy storage to hybridize or electrify heavy industrial equipment. Purpose engineered for the rigors of the commercial maritime industry, SPBES is safer and longer lasting than any other product on the market.”

    You can read the full GeekWire article here.

  • A small ferry’s battery fire deserves global attention

    A small ferry’s battery fire deserves global attention

    Excerpt from ShipInsight Article. Published by Paul Gunton · 23 December 2019
    You can read the full article here

    A seawater fire extinguishing system that had been installed as an additional safety precaution on the Norwegian battery-hybrid ferry Ytterøyningen may have “contributed to escalating” events that led to an explosion that struck the vessel on 11 October. It followed an onboard fire the previous evening, according to a preliminary report into the incidents published last week by battery supplier Corvus, but what caused the blast is not yet known.

    Although the vessel was a small local ferry operating on a short route in western Norway and the fire had been detected when the vessel was just 200m from its berth at which it docked safely, I believe this incident merits worldwide attention. With battery hybrid power systems becoming more common and an expectation that they will take an important place in the path towards zero-carbon shipping, a fire and explosion involving batteries should alert system designers and operators that this is not a risk-free option.

    However, this was the first fire in a battery ferry in Norway and we should be grateful that this wake-up call has been sounded on such a vessel as this, rather than on a large passenger ship far out to sea.

    Read the full ShipInsight article here.

    For more information on battery safety see our latest post on how battery technology can reassure industry safety concerns.

  • How can battery technology reassure industry safety concerns?

    How can battery technology reassure industry safety concerns?

    Written by Brent Perry, CEO, SPBES
    Published in ShipInsight, see link for article here.

    The shipping industry is currently finding itself at a vital transition point with respect to creating a more sustainable future, and with it, embracing the opportunity of lithium-ion technology as an increasingly viable energy storage solution.

    Just by looking at the increasing prevalence of the electric and hybrid vessels as a barometer for pace of change, it is indeed a promising future for the lithium ion energy storage system (ESS). The cruise and ferry industry are increasingly looking to lithium-ion batteries as ESS within their electric-hybrid vessels. This is especially true in Norway, where regulators and owners are leading attempts in adopting electric shipping to power the hundreds of cruise and ferry routes to make the fjords a carbon-neutral zone.

    The recent fire on board the Norwegian ferry, Ytterøyningen, however, has brought the safety issue of batteries at sea into focus. As with any new propulsion technology, it is essential that the industry understands the best practices that go with managing risks and how design, installation and operation of batteries can ensure that they are safe.

    Preventing Thermal Runaway

    The biggest risk surrounding the lithium-ion ESS is thermal runaway. This manifests as a positive feedback loop of increasing battery temperature.

    This can occur after being subjected to mechanical abuse or operating over, or under, the correct voltage or internal temperature. In these situations, heat may be generated within the lithium-ion cells which may in turn increase to a point whereby it melts the separators inside the cells. This causes a reaction between the cathode material and electrolyte and can result in the temperature increasing until the cell vents toxic and flammable gasses. If ignition occurs, these gasses can create an unpredictable fire which can be very difficult to extinguish. In large enough concentrations in an unvented room, these gasses are also capable of creating very large explosions.

    So what solutions are available when it comes to mitigating the risk of thermal runaway within a lithium-ion battery?

    Battery design is key in this instance. The use of complete liquid cooling systems is one verified approach to managing battery temperature, whereby chilled water is circulated through the core of a battery. Liquid cooling, as opposed to air cooling, cools both the interior and exterior of a battery unit. As well as being more effective, liquid cooling has been proved to be far more efficient than air cooling, which requires 3500 times more air flow volume than water flow volume to achieve the same heat removal. To try to compensate, the battery room for an air-cooled system requires a both a robust HVAC system and a way to evenly circulate the cooled air over the individual cells, an extra cost not typically included in the battery price by the battery vendor.

    Mitigating the risks of fires resulting from thermal runaway is only the first layer of protection that ESS must incorporate if they are to be used safely. The risk of a fire cannot be removed in its entirety, so failsafe mechanisms have to be in place in order to reduce the risk to the crew and vessel. Venting mechanisms can remove the flammable gasses away from an unstable battery, reducing the risk of a battery exploding.

    Battery Lifecycle and Safety

    The age of batteries is also a factor in managing risk. Naturally, batteries towards the end of their operational life do present the biggest risk to vessels as the cell materials degrade. This can be mitigated, to some degree, by systems, such as SPBES’ CellSwap system, which allows owners to use smaller systems with a shorter lifespan – negating the need for an over-sized battery that compensates for degradation over time. In this system, battery cells can easily be removed from the rest of the battery and replaced after five years, rather than the standard ten-year lifespan. This means that the batteries used can be smaller, which in itself reduces risk (as well as saving weight and space). It also means that batteries suffer less degradation. Liquid cooling also mitigates risk, as it stops batteries heating up unevenly.

    Smart Charging

    Another factor in ensuring safety is the integration of an intelligent battery management system into the wider automation systems of a vessel. This allows accurate monitoring of voltage and temperature of the lithium ion cells, and links directly to the alarm system. It also allows batteries to charge intelligently – slowing the rate of charge as the battery fills up to avoid overcharging, similar to the charging technology used for electric cars. As long as this system is in place, there is little additional risk to charging batteries as opposed to any other high voltage ship-to-shore power link.

    Best Practice

    Complementing a good design with best practice for safety and thermal management is the first major part of managing the safety concerns that accompany lithium-ion ESS. As there are safety practices for every power solution, whether it is bunker fuel oil, LNG or methane, safe operating practices are fundamental when it comes to marine batteries.

    In the wake of the Ytterøyningen fire, Norwegian Maritime Authorities have issued two safety recommendations: that battery units on hybrid vessels should be connected at all times to alarm systems and regular risk assessments are carried out on battery units.

    Recycling

    Mirroring their operational environmental credentials, how can marine batteries be environmentally friendly when they’ve reached the end of their operational life? Akin to embedding safe design, constructing batteries out of recyclable materials is a big leap forward in improving the eco-credentials of marine batteries. Ordinarily, when a battery comes to the end of its life, the whole system must be recycled and replaced with new components. Companies like SPBES have taken on this problem by designing a battery system with a 30-year life that includes CellSwap every 5-10 years. Replacing only the cells leaves the balance of system in place and significantly reduces the amount of recycling needed. The cells are certified as recycled, and the clients have clarity on the total environmental impact of their ESS. In other cases, where the entire system has to be replaced every 5-10 years, the recycling impact can be significantly higher, with no managed overview to ensure total recycling. This usually requires replacing a plastic housing and internal components held together with glue, creating a large amount of waste. As we see it, a better option is to recycle only the cell as most of the parts of a battery cell, including the rare earth metals used to create it, can be recovered using the latest recycling techniques.

    It is encouraging to see the shipping industry take steps into exploring the use of electric hybrid vessels. However, as with any transformation, there will be concerns, especially with something as deadly as fires and explosions.

    Therefore, it is vital that marine batteries have safety embedded within design, as well as operated alongside robust safety procedures. This will allow a greater scale of update and lead to widespread benefits realisation.

     

    Published in ShipInsight, see link for article here.
  • Safety Concerns for Hybrid & Electric Ships

    Safety Concerns for Hybrid & Electric Ships

    By Brent Perry and Grant Brown, Sterling PBES Energy Solutions (SPBES)

    Preface
    On October 11, 2019, an explosion rocked passenger ferry Ytterøyningen while dockside at Sydnes, Norway. The vessel, recently refit with a lithium-ion battery hybrid drive, is part of the new fleet of low and zero emission vessels being deployed across Norway and other parts of the world. The vessel was at dock having been pulled from service the night before due to a fire in the lithium propulsion batteries; a condition known as thermal runaway. The root cause of the fire is still to be announced, but the secondary explosion caused significant structural damage to the vessel; likely a result of a buildup of flammable gasses below deck. Thankfully none of the 15 people admitted to the hospital were badly injured and all were soon released.

    The concern of all parties in this industry is the root cause of the fire, the explosion and the impact of this event on our industry currently. The impact to future vessels incorporating lithium storage systems also must not be ignored.  Based on a lifetime of experience in the marine industry, the following are my personal opinions and observations about how we can reduce passenger risk and increase vessel safety and reliability.

    History

    When we founded this industry in 2009, the initial concerns that we had to address were centered initially around actual performance and safety.  The questions were simple: Does large scale lithium energy storage actually have the capability to optimize or replace fuel driven engines? Can this be done with the same safety and reliability of current commercial marine systems?  The next consideration was cost: Could lithium ESS actually match or improve the financial operating costs of commercial marine installations?  And lastly, did lithium energy storage improve the environmental impact of the commercial marine industry.

    At the time, lithium ESS was priced at around $3000/kWh, making it too expensive for widespread commercial adoption, and it was not available in a form factor that could support industrial scale marine installations.  Simply put, the technology was not commercially viable.  This lead me and my partners to take advantage of our unique position as marine people with strong battery knowledge to design the first “fit for purpose” lithium battery; one that was scalable to deliver MW scale power on a continuous basis.  Our efforts, along with the support of the type approval agencies, flag authorities, fleet operators and system integrators (and a host of un-named people who all supported the dream of an emissions free marine industry), led to the acceptance of the use of lithium ESS in support of both hybrid electric installations and full electric vessels.

    By 2014, the price of lithium ESS was approaching $1000/kWh and was regarded as a commercially acceptable solution in the marine industry, centered on Northern Europe and Scandinavia.  Government legislation in this market area presented us with an opportunity to support environmental targets, while delivering better financial results than conventional technology. An added bonus was actually reducing risk and improving safety of vessels overall.  There were still a lot of challenges. We were all learning as we went about how to engineer better and safer systems. At this point other companies saw a viable market and a chance for successful commercial use of their own lithium-ion solutions.  The revolution was firmly rooted and taking hold of the industry.  Most newbuilds were considering use of ESS in some form and many systems were being deployed.

    Of course, the challenges started to grow as well. Now that we knew it worked, we had to figure out how to make it safer and more reliable while reducing cost.  There are a lot of lithium solutions that are significantly cheaper than what meets the unique needs of the marine industry, but these are produced to serve markets with very different performance requirements than exist in commercial marine.  The inflow of battery supply has created a growing demand on the type approval agencies and government authorities to further define the standards and safety criteria. The overwhelming number of technologies available present a dizzying variety of potential issues to anticipate and manage in defining the standards.

    “In the rush to make this technology affordable, we cannot avoid the necessary steps to maintain safe operation. Safety is first and paramount always.”

    Brent Perry, CEO, Sterling PBES Energy Solutions

     

    Evolution

    Experts estimate that all modern commercial vessels will soon have some form of energy storage on board. Each year there are more and more hybrid or fully electric ships navigating waters worldwide. These ships range in type from ferries transporting thousands of people daily, to offshore supply vessels and now even cruise ships. These vessels increasingly rely on lithium-ion energy storage as a power source, with modern designs containing hundreds of individual modules (batteries).  The technology has proven itself reliable and powerful, but lack of performance history means lessons in safety are being acquired through daily operation. This is new technology and knowledge is being gained in real time.   Safety systems need to be validated and must be kept as the highest priority.

    As the industry founders that brought the first purpose designed energy storage to large marine projects, here is our opinion on what changes need to be made to improve safety.

     

     

     

     

     

    The ferry Ytterøyningen at Brekstad. Photo: Alexander Killingberg

     

    Testing & Certification

    One of the biggest risks for batteries is not just fire, it is overall thermal management.  Onboard the Ytterøyningen, the fire may have appeared to be under control, but the possibility for a lithium fire to continue to smolder is very real. As long as there is energy within the cells, risk remains of further fire and gas production. In our early days, our engineers were involved in automotive testing. In the course of these tests we observed one lithium fire that (in a controlled environment) took two full days to fully exhaust its energy and ultimately be extinguished. Aboard Ytterøyningen, I suspect that the batteries were damaged in some way and additional lithium-ion cells continued to fail after the initial fire occurred. The subsequent thermal runaway produced the gasses that ultimately led to the explosion the next day.

    Thermal runaway occurs if the lithium-ion cells used in marine batteries are subjected to mechanical abuse, suffer from internal manufacturing defects, or operate over or under the correct voltage or internal temperature. In these situations, heat may be generated within the lithium-ion cells which may in turn increase to a point whereby it melts the separators inside the cells. This causes a reaction between the cathode material and electrolyte and can result in the temperature increasing until the cell vents toxic and flammable gasses. If ignition occurs, these gasses can create an unpredictable fire which can be very difficult to extinguish. In large enough concentrations in an unvented room, these gasses are also capable of creating very large explosions.

    The minimum requirement for batteries used in commercial vessels in Norway is the Propagation Test Type 1. To receive certification this test is repeated three times and is intended to show prevention of propagation of the thermal event from one cell to the next. Simply put, this test means that if a cell in a single module ignites, fire may consume the single cell but will not enter thermal runaway and ignite the other cells in the module; thus the larger system remains safe.

    Isolating a thermal event to one cell makes sense but reliance on this standard on its own creates potential problems:

    1) The gasses that escape from even one cell are very flammable and are dangerous in an enclosed space. Proof of management of dangerous gases is required.

    2) What occurs when more than one cell is involved right from the beginning of the event?

    3) What happens when a module full of cells fails or even an entire system?

    4)  How can software help to predict and prevent a physical incident?

    Testing to validate the design of batteries needs to expand to incorporate the risks we identify above.  There is enough demonstrated market in the growing use of ESS to rationalize the furtherance of testing standards. It is a natural next step and will keep the focus on best engineering practices all around to minimize risk.

     

    Testing – Next Generation

    The technology exists today to nearly eliminate risk of battery failure, starting with fundamental safety systems that are not uniquely dependant on software. These hardware-based systems are complimented by software that can effectively alert the operator of real risk. Further, they must be incorporated with system testing to define the risks for whole system failures.  This means that in testing a system, it has to be able to demonstrate gas extraction; that is removing risk of gas exposure to crew and firefighters and dispersing it so that the risk of explosion is mitigated.  Safety testing must involve overcharging a pack so that cell failures are forced in more than one location, so that total safety management can be observed.  It requires software that is able to continue to deliver important voltage and temperature related alarms at all times, not just when a system is in operation.

    Combined with existing tests, this next generation of testing will be a very strong forward step to reducing the fears of operators. It will inspire reputable battery companies focussed on the needs of the industry to be better partners and prevent the others from bringing inappropriate solutions to market. This will reduce commercial risk instead of creating inevitable issues on board the very vessels that are at the core of this growing market.

    The image is a screen capture of an SPBES baseline test to show the energy contained in a single cell. A typical commercial vessel may carry many thousands of these cells.

    Image 2 Lithium Cell Fire.JPG – Link to https://youtu.be/kZsqzAx-Svs 

     

    The Solution – Prevent Thermal Runaway

    Liquid cooling is the only safety system currently tested and proven to prevent thermal runaway. These active cooling systems prevent batteries from entering thermal runaway by simply extracting more heat than the cells can produce. Similar to an engine block of an automobile, a low pressure, high volume closed loop of chilled water is circulated through the battery. SPBES has developed a proprietary and patented cooling system that takes this idea one step further and circulates coolant through the very core of the battery, around each individual cell in the system.  SPBES CellCoolTM is able to remove more thermal energy than the cells can produce when in an overcharge or damage scenario, effectively preventing the cells from achieving the temperature needed to go into thermal runaway.

    Independently validated testing shows that the SPBES system is so effective that it works even if the coolant pump is disabled. This means that even in the event of catastrophic damage to the vessel’s electrical system, the system will still protect the batteries. Due to its patented design, CellCoolTM also eliminates hot spots on the cells and maintains optimal cell temperature – thus increasing cycle life and overall lifespan.

    In comparison, forced air cooling only cools the external surfaces of the cells and is ineffective at eliminating hot spots in the cells. An air-cooled battery requires around 3500 times more air flow volume than water flow volume to achieve the same heat removal. To try to compensate, the battery room for an air-cooled system requires a robust HVAC system, an extra cost not typically included in the battery price by the battery vendor. A system using a chiller plate is only able to cool one single surface of the module and is therefore unable to fully prevent hot spots or remove all of the thermal energy contained in a lithium-ion battery.

     

    Additional Safety Considerations – Thermal Barriers and Venting

    Effective internal thermal barriers are an essential part of lithium battery safety systems. SPBES Thermal-StopTM is a metal barrier integral to the structure of the battery that works similar to a firewall. It prevents an overheated, overcharged or damaged cell from propagating to the adjacent cell. The event is therefore isolated to one cell and does not affect the others. Ignition does not jump to adjacent cells because of the metallic barrier between them. Because SPBES batteries have a solid metal internal assembly, they are in effect armored and resist mechanical damage from external forces.  Even in the event of a totally spontaneous combustion, the cooling system is able to prevent propagation from cell to cell.  In testing of spontaneous cell failure, cell temperature approached 500 degrees centigrade, but the adjacent cells never were hotter than about 80C. Upon disassembly, the adjacent cells showed no visible damage – they looked like new.

    The image is a screen capture of an SPBES thermal runaway test. Even with the cooling system disabled no thermal runaway event occurs. The graph shows the voltage and temperature increasing to the point of cell failure, and the subsequent cooling. In an air cooled system this thermal event could continue for hours or days until all the energy is released.

     

    Image 3 Thermal Runaway Test.JPG – link to https://youtu.be/e3ZOvwBUmx0

    In the event that a cell is damaged or overheated within a module, dangerous gases are released.  It is therefore important for every battery systems to be vented to protect the crew from exposure and protect the vessel from explosion. E-VentTM is another SPBES patented system to vent flammable gasses safely away from the battery area using a one-way valve that opens at low pressure. Gas is removed by an explosion proof fan that operates continuously or upon heat or gas detection.  When gas flow stops the valve immediately closes, restricting flow of air or gasses back into the battery. This simple system reduces risk of crew exposure or a secondary explosion. It thus allows the crew to safely re-enter the vicinity of the battery system sooner to make repairs and restore power.

    Using the SPBES CellCoolTM system, the cells simply do not combust. In fact, when modules used in standard overcharge testing were disassembled and inspected, the cells that had been overcharged looked virtually identical to untested, brand new units, save a small rupture on the top of the cell near the terminals. Despite the fact that virtually no gas has been detected during these tests (typically a 75Ah cell can produce 120l of gas, with liquid cooling we reduce this amount to around 800ml), we understand the potential risks. Every system we install has integrated CellCoolTM and E-VentTM systems installed.

     

    Conclusions – Will it happen on your watch? 

    Given the rapid uptake of the use of large format lithium-ion batteries it is difficult for regulators to stay abreast of technology changes. I believe it is in the best interest of the maritime industry to do everything possible to ensure crew, vessel and environmental safety. As the thought leaders of energy storage in the maritime industry, SPBES has always been willing to licence its safety systems to other manufacturers in order to improve safety. We are willing to help any organization, be it regulatory or supplier.

     

    About SPBES

    Since developing our system, SPBES has installed 21 MWh of lithium storage on 17 vessels. SPBES energy storage is the only energy storage system proven to stop thermal runaway. It has been engineered with performance and safety as the two guiding principles that direct the design. The resulting liquid cooling system is the only one that makes the battery last longer, work harder and ultimately reduce risk.

    Please contact info@spbes.com for more information.

    For news about SPBES or to sign up for news updates, please visit SPBES.com.

    https://spbes.com/battery-news/

  • SPBES response regarding recent fire and explosion on board ferry Ytterøyningen

    SPBES response regarding recent fire and explosion on board ferry Ytterøyningen

    As a leading Battery System provider to the Marine industry, SPBES has been asked to provide a response in regard to the recent fire and explosion in the battery compartment of the ferry Ytterøyningen.

    Battery system safety is the primary concern in any system design. SPBES has designed several layers of safety into our system to ensure that there is reduced risk of a similar event occurring with one of our systems. The primary safety feature is our closed loop water cooling system (CellCool ™) that is independent of the operation of the battery. This means that in the case where an individual battery unit, or indeed even a full string(s) is offline, the cooling system stays in operation whether or not the batteries are connected. In addition, we have run extensive destructive testing in our lab where we caused cells to fail inside our battery, and successfully stopped the resulting thermal event without experiencing any sort of thermal runaway. All gases were vented properly and safely through our ducting system and the adjacent cells were maintained at safe temperatures.

    SPBES normal operating procedure is that when an individual string is not connected, the cooling system runs continuously, but the string control unit (called an MBU) does not communicate to the ships control system until the string functionality is restored. As an added measure, we are amending our procedures to maintain communication between the MBU and the customer interface when a disabled string is not in operation. This procedure can be implemented immediately, but may in some cases require manual installation of a software update by SPBES in coordination with our customers. We are currently assessing the effort to implement this feature in our system as a standard procedure and expect to have a plan for that by the end of October.

    Please do not hesitate to contact us directly if you have any concerns or questions, info@pbes.com.

    You can download the PDF version of this here.

  • Practical Application of Energy Storage

    Practical Application of Energy Storage

    Excerpt from The Journal of Technology, written by Grant Brown, VP Marketing SPBES.  Published November 2018.  Read full article here.

    Marine engineers have long been aware of the potential efficiency increases from hybridizing their onboard energy systems; the ability to optimize the use of diesel generators by storing excess energy and using it to provide propulsion during low load times. However, only recently has the battery technology been improved to the point of allowing large-scale systems to survive in a commercial marine environment. Not only do these new energy storage systems survive, they are designed for and excel in commercial marine environments. Hybrid tugboats, offshore supply vessels (OSV), ferries and a variety of other purpose built vessels all derive huge efficiencies from the use of onboard energy storage.

    These hybrids range from new builds to retrofits of existing vessels. Payback on investment is a critical component in the decision to convert or build a hybrid workboat. However, an often overlooked benefit is the redundancy and increased safety offered to the operator of a hybrid vessel. A vessel employing a large battery or energy storage system (ESS) not only operates more efficiently, it also has an ability to draw upon a reserve of energy instantly. This pool of energy may be used as spinning reserve to keep the vessel from harm’s way in the event of power loss, provide emergency navigation and hotel loads, auxiliary propulsion power, and even extra bollard pull to the main drives in the event of an emergency situation while towing. While these and other advantages, such as the environmental and cost savings benefits, are well-documented, real world lessons learned by an experienced integration and engineering team are exceptionally valuable. This experience helps vessel owners, operators and designers understand how to design and integrate a lithium energy storage system for safe, reliable use, now and for years to come.

    Simply put, batteries will reduce a vessel’s exposure to risk and make it fundamentally safer to operate, while providing economic gain for vessel owners.

    Risks of Energy Storage
    Despite the obvious advantages to a vessel using energy storage to increase efficiency, redundancy and safety, the batteries themselves may pose risk. Due to an event known as thermal runaway, the batteries, if not managed within certain and specific parameters, may pose risk of combustion.

    Lithium ion cell forced into thermal runaway – all safety mechanisms disconnected.

    Thermal runaway occurs if the lithium-ion cells used in marine batteries are subjected to electrical or mechanical abuse, suffer from internal manufacturing defects, or operate over or under the correct voltage or temperature. Heat is generated within the lithium-ion cells and in cases where this heat exceeds a specific temperature (usually in excess of 120˚ centigrade), the internal structure of the cell begins to degrade. This degradation results in the internal separators melting and thus causes a reaction between the cathode material and electrolyte. This can result in the cell temperature increasing until the cell vents toxic and flammable gases. If ignition occurs, these gases can create an unpredictable fire, which can be very difficult to extinguish.

    Therefore it is extremely important to a) reduce risk by designing and manufacturing the highest quality product available, b) reduce risk by managing the batteries in the safest possible way and c) provide a system that is capable of containing and suppressing thermal runaway should it occur. While we have come to accept the risks of maintaining large quantities of flammable diesel on board a vessel, it is due to decades of experience that we now have very little incidence of diesel fire. This is due to trial and error, consistent regulation, and adoption of best practices for management of the systems.

    The same learning curve is occurring in the marine industry regarding large-scale lithium batteries. Currently, regulations do not reflect the realities of the size and types of systems that are now being installed and while it is unfortunate, it may take some sort of significant incident to force the industry regulators to adopt stricter regulation.

    Fire Suppression
    Given the possible issues associated with fire and explosion, the class groups have spent a lot of time focusing on how to prevent and manage fires and thermal runaway. No matter the amount of care that the class rules can apply to prevention, it does not remove the battery manufacturers from the responsibility of incorporating sophisticated prevention systems into the design of the batteries. With lithium energy storage systems now regularly being discussed that exceed several MWh of capacity, the risk of thermal runaway or fire cannot be taken lightly. Today’s hybrid designs must take this into account and do everything possible to ensure that a fire cannot start in the first place. This has created a shift in thinking that is driving designs to incorporate liquid cooling systems. These liquid cooling systems manage battery safety inside the core of the module through temperature control and management at the cell level. Fire suppression is critically important but must be viewed as a secondary system to manage the issue in extreme circumstances, after all else fails. Fire suppression systems therefore are recommended to control external fires adjacent to the energy storage system to prevent them from causing a thermal event in the battery room. If desired, fire suppression in the battery room may also be employed to further give peace of mind as a backup system. Mist type fire suppression provides adequate cooling to suppress virtually any fire (outside of a major catastrophe involving the ship itself) that may pose a hazard to the energy storage system. In order to meet class standards, the energy storage system itself must be rated for IP67 water resistance and therefore able to safely withstand activation and use of mist type fire suppression.

    Management Systems, Communications and Controls
    Modern battery systems provide an ability to not only integrate with existing systems on board the vessel, but also increase longevity of system life and enhanced safety of the system. These systems reside inside the battery modules and the system controller, which in turn communicates with the other vessel power electronics. The Battery Management System (BMS) is able to predict module lifespan using complex algorithms that incorporate historical data and projected future use. This allows vessel owners to alter their use profile of the energy storage system to a) increase lifespan, b) increase vessel fuel efficiency, or c) a combination of both. The BMS is also an extremely important part of the safety system of the ESS. It constantly monitors the internal core temperature of the modules and if they are going out of spec (too hot or too cold), they will warn the vessel captain to limit use. The BMS is also able to actively monitor the state of health of the system within the temperature warnings; if a specific component in any one part of the entire system is out of spec, the system will warn the captain and the team who is monitoring it. The monitoring team will then proactively engage with the vessel and determine what, if any, course of action need be taken. If the warnings continue without intervention from the team, or if the vessel crew ignores the warnings, the system will protect itself and the vessel by disengaging from the DC bus and isolating all the modules in the system via their internal contactors, effectively reducing system voltage from a maximum of 1,000 V to ~100 V (the voltage of a single module). As the controls are powered separately from the ESS, they are safer in that there is redundancy in the system. It will always have an external power source ensuring the cooling system is operating and the management system is communicating with the vessel and system administrator team at all times, regardless of the system status.

    Cooling Systems
    While the industry standard for many years was passive cooling on all systems, it is increasingly apparent that the smaller systems demanded by industry are required to operate at, or beyond, the limits of passive cooling. Virtually all modern ESS employ some form of liquid cooling, either as an optional addition to the standard system or as an integral component. Advanced, state of the art ESS use individual cell level cooling systems; the coolant circulates within the very core of the battery module at a low pressure enabling far greater charge and discharge currents, increased lifespans, and reduced system sizes. In fact, the most modern of these systems has been validated to discharge approximately 16 times more power than the current industry standard product. Typically the ESS will connect to a standard chiller of specified size, using an inexpensive and small pump and be able to meet the very high demands with a far smaller system size and capacity with resulting cost savings benefits.

    Conclusion
    The new breed of hybrid commercial vessel is now a proven workhorse capable of huge economic and environmental benefits in virtually every application it is deployed (Figure 5). The added risk mitigation and increased safety has tangible value that should not be dismissed. No longer is the reduced cost of ownership from the decreased fuel consumption and maintenance outweighed by concerns about safety and reliability. As with any updated technology, lithium energy storage is new and system design is currently being refined, as are class rules regarding the use of the technology. As a co-founder of one of the early companies developing energy storage for hybrid marine systems, I have observed the industry develop, grow and mature. It is my assertion that the technology is gaining momentum by leaps and bounds. As it continues to evolve so will advances in the design and safety of the systems and increasingly strict regulations governing their use. The industry is now producing safe, reliable systems that provide meaningful financial benefits for the owners, safe operation for the crew and, ultimately, huge environmental benefits for the planet.

    Read full article here.

  • A Battery Room Fire

    A Battery Room Fire

    [vc_row][vc_column][vc_column_text]“In the rush to make technology affordable- we cannot avoid all the necessary steps to stay true to the reality of our markets- Safety is first and paramount always.” Batteries have made incredible progress in the last ten years and are an integral part of the solution- financially, environmentally and socially. Our thoughts go out to all of the first responders affected by this event- godspeed your recovery. – Brent Perry, CEO SPBES

    Below is an excerpt from OffShore Engineer published October 15, 2019 by William Stoichevski about the recent battery fire on-board the MF Ytteroyningen. Link to full article here.

     

    A Fire in the Battery Room

    The fire on the night of October 17 occurred just a hundred meters from shore, and “passengers and crew got to land before the situation escalated”, NRK reported. The fire aboard the ferry MF Ytteroyningen, reported by Norwegian national broadcaster NRK, was a stark warning. It escalated. The fire in the battery room was thought to have been extinguished during the night, but an explosion below deck rocked the converted hybrid ferry in the morning. Damage is severe and structural.

    The risk inherent in marine energy storage has, however, been known and understood — by a few. Little-known lab tests in Sweden produced fires.

    Canadian entrepreneur and shipbuilder Brent Perry, behind both Corvus and PBES (now SPBES), has cautioned about thermal runaway and fumes build-up for years, adding that some competitors don’t understand risks that need to be mitigated via special safety mechanisms.

    Brent Perry (Photo: William Stoichevski)

    Rig risk
    The risks need to be thoroughly understood and responded to given the implications of the MF Ytteroyningen fire for rigs or the offshore service vessels hoping to rely on energy storage. Was it the ferry’s battery room construction that caused the explosion and fire? Was it a flaw in the energy storage system itself?

    Rig owners and operators need to know what caused the metal-melting battery fire aboard that ferry before more marine batteries are installed on anything destined for an offshore hazard zone. Early investigations reveal the batteries weren’t plugged in.

    But what caused thermal runaway in the first place.

    Perry once told this author that the systems have to robust enough not to need their own battery rooms, where fumes can gather. Batteries need to speak to technicians, and then they need to be kept at stable temperatures. Their control programming needs to be adjusted.

    I’d talk to Perry, as he seems to have written the rules on energy storage safety.

    “We monitor these systems 24/7. If we see a slight variation in voltage, we know it before the customer does,” we once quoted him as saying.

    “Lithium batteries — although they have extraordinary performance capacity — are very temperature-sensitive beasts.[/vc_column_text][/vc_column][/vc_row]