Lithium Power Energy Systems for the Next Generation of Vessels. Power for a Green Future

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1 Vancouver, Canada Organised by the ABR Company Ltd Day 2 Paper No. G2 Lithium Power Energy Systems for the Next Generation of Vessels. Power for a Green Future Brent Perry (speaker/co-author), George Roddan (co-author), Neil Simmonds (co-author), Corvus Energy Limited, Canada SYNOPSIS A brief description of the benefits of lithium energy battery technology, will be followed by a brief history of its growth, and a comparison of modern battery systems. There will then be brief descriptions of working scenarios and the benefits of hybrid and electric applications, including an outline of how to mitigate costs, improve ROI, and develop an understanding of the impact on the environment. The paper will touch on all aspects of the benefits of using lithium technology today, and how it will be impacting the future of vessel design, construction and use in today s vessels. It will demonstrate the financial and environmental gains that are possible today. THE BENEFITS Lithium energy storage is quickly becoming a costeffective alternative for vessel designers, builders and fleet owners. The technical capabilities of lithium-driven energy are offering the current generation of vessels changing parameters in systems in the following ways: Has stable, reliable and safe chemistry and systems that provide years of consistent and quality performance to meet the growing demand for more sophisticated and power-hungry vessel systems; Offers complimentary power that optimises the performance and extends the life of diesel power drivelines; Provides power to replace diesel drivelines with no compromise in performance for specific applications; Offers vessel systems designers an alternative source of high energy/power that creates the opportunity to re-design systems and reduce system complexity and costs throughout the vessel; Offers the commercial marketplace an alternative power supply that reduces harmful emissions generated by fossil fuel engines, thereby improving the environmental footprint of commercial marine fleet operators without compromising performance; Creates the opportunity through the generation of carbon credits to monitor and measure the impact of electrified vessels on the environment. BACKGROUND To better understand the role of lithium energy technology, we will first supply a brief history of the development of the lithium battery and its applications across the world that has led to the current situation. 1 Presently, lithium ion technology is poised to take over and dominate a new marketplace as its values and abilities become evident and the return of investment models become feasible to commercial operators today. EARLY HISTORY Due to cost and power management limitations, lithium batteries were first applied in very small applications such as RC models and telephone handsets, and gradually migrated into small technology applications such as cameras, laptop computers and hand-tools. The technology proved its value in each application, and began to dominate the small re-chargeable market places. As time progressed, the design of the batteries advanced and technology behind the battery management systems became more sophisticated, improving the performance and cost effectiveness of each application. This enhanced performance, and a reduction in costs, led to lithium ion dominating the small re-chargeable battery field globally and displacing the majority of small battery technology that was used in these applications. The leading chemistry in this sphere, due to excellent performance characteristics, compact packaging and cheap costs, is the lithium iron phosphate cell. It is ideally suited for applications such as laptops and power tools: applications where its principal features are very well applied, and the size of the cells is ideally suited for small output applications. RECENT HISTORY The next field to be a focus of lithium energy battery technology was the motive power field, principally the automotive industry. The demand here was for mediumsized power packs, up to 30kWh in size. It is here where

2 the features and benefits of lithium iron phosphate began to have less appeal and develop more challenges. Designers and engineers found that in order to meet the overall power needs of the automotive packs, thousands of the small cells of lithium iron phosphate had to be assembled together to be able to create the amount of power needed to operate a vehicle. In every case the issues surrounding efficient and repeatable quality and manufacture were a challenge, as well as the ability of battery management systems to effectively manage the volume of individual cells combined with the use of several charging sources (braking, alternators, remote charging stations). It was at this time that the development of large format lithium polymer cells was coming to maturity. Chemistry, manufacturing and management processes could now combine to produce cells with the power, energy storage and discharge features that are critical to the success of engineering battery packs that start at 6kWh and can be scaled to sizes (literally MWhs) that actually challenge and offer real alternatives to fossil fuel power-plants. Until today, that has not been possible to achieve. The chemistry of the cell that we are describing is Nickel Manganese Cobalt, or NMC, manufactured by Dow Kokam, and it is ideally suited for high power marine applications for the following reasons: 1. In either energy or power ratings, lithium polymer is the most effective chemistry commercially available today; it can deliver the needs of a vessel within the smallest possible weight and size footprint. NMC lithium has 22 per cent more energy than iron phosphate and 88 per cent more energy than lead acid batteries. In power applications, NMC is again 22 per cent more powerful than iron phosphate and 76 per cent more powerful than a typical lead acid battery. 2. Discharge capability affords the operator the full use of available power at very consistent voltages, even up to 10C discharge rates. This means we can operate all machinery until the end of the discharge life of the battery, even with very large loads, without seeing the battery voltage drop to levels that machinery cannot operate at. Simply put, they push more energy longer, and can do this over and over again. Lead acid batteries are not designed to operate at this level of performance, and to do so would require such large packs that storage and weight would become significant challenges. 3. Charge and discharge efficiency is superior to any battery technology available today. NMC cells offer the least amount of resistance due to the patented folding technology that Dow Kokam owns, resulting in very high capacity cells up to 250 amp hours per cell that operate at a charge/discharge efficiency of 99 per cent. Iron phosphate chemistry is manufactured as a carpet roll and the energy has to run around the roll until it is finished, resulting in a charge/discharge efficiency that is at best 95 per cent. Lead acid batteries typically operate at approximately 60 per cent charge/discharge efficiency The manufacturing process is critical to the performance of large-scale battery packs. Dow Kokam has a patented manufacturing process that is nearly 100 per cent robotic, delivering cells of the greatest consistency in the world today. The foundation of our battery technology is made up of cells that all work and perform within a very specific voltage and amperage level. The larger the battery pack, the more important the consistency of the cells to the overall performance. Safety is critical and the Dow Kokam cells are each individually fused so that should a critical energy level occur (20C discharge), the cell s built-in fuse will fail and shut the battery down to prevent an explosion or a fire from occurring. 5. Reliability is the other critical foundation feature, and the Dow Kokam cells are the proven leader in this field as well: this has been proved by the selection of Dow Kokam cells in many critical military, space and aviation industries. Dow Kokam cells are the only cells approved for use in commercial airliners, and are aboard the Boeing 787 Dreamliner as a power supply. BATTERY MANAGEMENT SYSTEMS In addition to the evolution of the lithium polymer battery cell technology, another stream of development has been underway, equally critical to the success of the application of the batteries: the development of the battery management system. Battery management systems are responsible for turning the cells into smart sources of power, and they exist in every modern battery made. In very small applications the battery management system will operate to determine charge remaining and tell the operator when to charge the battery, as in a cell phone. In large battery packs, the demands and requirements are much more involved and far more critical to the overall performance and lifespan of the battery bank. Our patent-pending technology in this field has resulted in a smart battery that monitors each and every cell in a battery as well as in banks of MWh size to create an equilibrium of performance and reliability, no matter how many different charge sources are available. Lithium polymer batteries are actively balanced, charge and discharge are managed and monitored, temperature and voltage are actively monitored and all of the data relative to performance is tracked to manage the overall performance, giving us the ability with lithium polymer batteries to support the applications with literal lifetime support and eliminate downtime due to battery failure. We also have the ability to introduce any number of safety alarms, all of which can be programmed to either shut down a system, isolate a system or in a worst case scenario the failsafes can be bypassed if the vessel or rig is in danger and needs to use the full power of the battery bank. The result of this is a battery that adds a new dimension to vessel design, where the standby power is the flexible partner of the designer and the vessel operator.

3 Chemistry Lead acid (AGM) Sodium nickel Chloride Lithium iron Phosphate Corvus lithium NMC Nominal Voltage 2.0V 2.58V 3.20V 3.70V Maximum Voltage 2.60V 2.9V 3.60V 4.20V Minimum Voltage 1.50V 2.0V 2.30V 2.75V Energy Density 20Wh/kg 100Wh/kg 129Wh/kg 163Wh/kg Power Density 75Wh/l 150Wh/l 255Wh/l 320Wh/l Cycle life (100% >1500 >3000* DOD) Internal Impedance >20 ohms 150 milliohms 3 milliohms 0.5 milliohms Charge Efficiency 60% 85% 95% 99% Operating Temp 40 o C to 60 o C 270 o C 20 o C to 55 o C 20 o C to 60 o C Self Discharge 4%/month none <3%/month <0.001%/month (20 o C) Cell Format Liquid filled box High temp box Manufacturing Foundry Partially Automated Cylindrical/ prismatic Partially Automated Layered Fully Automated Comparison between lead acid, sodium nickel chloride, lithium iron phosphate and Corvus lithium NMC. What does this mean to a large footprint battery pack? Voltage The lower the operating voltage of the cell, the more cells required to attain the required voltage of the pack, eg for a 320 volt pack it will require 160 lead acid cells or 124 NaNiCi cells or 100 iron phosphate cells or 86 Corvus NMC cells; Energy density a higher energy density cell will give you longer running times than the lower energy density cell or the same running time with a smaller pack (this has an impact on the size, weight and cost of the pack); Power density a higher power density will permit you to accept or deliver higher current surges (this, again, has an impact on the size, weight and cost of the pack); Life cycle has a direct relationship to the overall cost including cell costs and cell replacement costs. The next generation of cells we will be using will incorporate new nanotechnology materials that are estimated to increase the life cycle by a factor of two; Internal Impedance the internal impedance is directly related to cell chemistry and to quality of manufacture. Lower cell impedance permits the cell to be safely operated at higher charge/discharge rates. Charge efficiency charge efficiency is directly related to internal impedance; Self discharge a lower self discharge means that the battery can remain dormant for a longer period of time without having to be recharged, thus reducing maintenance. It should be noted that NaNiCi cells do not have a self discharge, but consume 14 per cent of their own energy to maintain the 270 degrees C for operation and, once activated, cannot be turned off; Cell format A liquid-filled box has been a simple packaging technique used for many years, but is bulky; a cylindrical cell is a good technique but wastes space; a prismatic cell is simply a cylindrical cell that has been flattened. This can lead to hot spots of high conductivity at the corners. A layered cell is the most recent packaging technique and permits higher capacity cells to be manufactured. Our cell supplier has the world-wide patent on this technique; Manufacturing a large footprint battery pack is only as good as its weakest link, therefore cell quality is extremely important. Manufacture in a foundry using manual labour does not permit consistent quality. Partially automated manufacture is an improvement, but only for the area of manufacture that is automated. There is still a quality issue with the sections that use manual labour. The only way to produce a large footprint battery pack is by using high quality cells that have been manufactured using a fully automated process. 3

4 CELLS AND BATTERY MANAGEMENT SYSTEMS The development of both the large scale cells and the sophisticated battery management systems has set the stage for the use of commercial lithium ion batteries in high power applications, specifically in this case the commercial marine industry. In understanding the needs of the marine industry, we determined that the key features of any large scale storage systems were based on the following needs: more and more systems come to rely on electricity as the primary source of power to operate. In order to optimise the ROI for the vessel operators, the battery systems also must be able to have a long life. Naval architects and designers require the support of lithium battery design engineers to be able to tailor the application engineering to optimise performance while keeping capital and operational costs to a minimum so that operators can enjoy the benefits that lithium inherently has over the industry standard lead acid batteries. 1. Have to be able to be 100 per cent reliable in use and in service: We designed the batteries in both energy and power applications, performanceengineered so that no matter the use, the battery and battery hardware are oversized for the application. Only marine grade materials have been used in the design and engineering of all of our battery systems. 2. Have to be 100 per cent sealed: If the battery is susceptible to moisture or water intrusion, the environment we operate in would be able to destroy the batteries in a short period of time. Largely due to the design of our cells and the controls we have with the battery management system, we do not develop thermal issues until the external temperature approaches 60 degrees C. Even the terminal points are made with sealed connectors, isolating the terminals from any degradation due to corrosion. 3. Have to have efficient charge and discharge characteristics: Due to the low impedance of our batteries, we are 99 per cent efficient in transfer of energy. 4. Have to be able to meet the needs of the vessel systems and drive systems: We can produce batteries in packs that can literally replace the diesel engines in vessel support while the diesel engines run up and come to power. If there were any compromise in performance, a battery-operated support or main system would be of no value to the operators or the industry. 5. Have to be seamless in operation: The operator has to be able to operate the vessel without switching modes or stopping to go from electrical to diesel application. 6. Have to be safe: With both mechanical and electronic safety features built in to the batteries, our battery packs and the chemistry that supports them is the safest battery technology available today. They will not produce any gas or by-products that are explosive or flammable in any way. The nature of the marine industry is a unique one from the perspective of the application. It requires all systems to be developed to operate under the harshest conditions on the planet, whether surfaceor subsurface-bound. The need for the systems to be functional at all times is absolute, and the work requirements of the marine industry require a battery to be 100 per cent reliable, and this responsibility grows as the applications broaden and 4 HYBRID DRIVE SYSTEMS Hybrid marine applications arise where there is a large intermittent fluctuation of load requirements, as in the case of harbour tugs and short-run transit ferry systems. Again, with the advent of large-scale lithium polymer battery systems, there is the opportunity to reduce operating costs by 50 per cent and emissions by 70 per cent. With the current move to reduce emissions and the need to lower operating costs, many commercial operators are looking to the electric solution, similar in some ways to the hybridisation in the automotive industry. In certain vessel applications, a hybrid solution makes sense in terms of reduced emissions as well as improved efficiency. In addition to general environmental concerns, legislation is coming which will demand the need for lower emissions in harbours. One key example is the harbour tug. This specialised tug is used to dock and manoeuvre large ocean-going vessels and faces the dilemma of having to provide thrust levels of up to 75 tons for brief periods of time, while loitering or operating marginally for up to 90 per cent of its time on duty. One proposed solution is to hybridise the vessels to operate in the electric mode during loiter and switch over to the high thrust/diesel mode during docking manoeuvres. There are approximately 2,000 coastal workboats in the world that are more than 40 years old and nearing the end of their service life. A minimum of 450 of these vessels will be replaced in the next five years and the remaining over the following five years. ELECTRIC DRIVE SYSTEMS Electric Drive Systems are ideal in port and harbour roles, meeting and exceeding the expectations of air quality management boards, local communities and the public in general. The reduction in emissions and noise pollution also contribute to a more healthy working environment capable of co-existing with residential and light industrial areas near to ports. Another critical advantage is the cost of operation, where the cost of inexpensive local grid power can be used to significantly reduce the cost of operation of the vessel and improve the return of investment that the operator has to make. There are also significant government incentives and grants in both North America and Europe for companies and operators that will commit to this level of emission reduction. The downside of this option today is cost, but this can be offset by the taking advantage of the

5 option of leasing, which will offer the vessel owner and operator the full advantages of zero emissions and the power of lithium while reducing the time to investment return to less than two years. Projected percentage cost of electricity to diesel (kwhr). THE ENVIRONMENT While the impact on the environment has been for a long time the last reason to improve systems, communities, governments and businesses are now recognising the need to improve our impact on the environment. Today, we have much more data and facts to determine the damage we do as well as measure the improvements we can make. The most obvious benefit of using hybrid or full electric systems is the reduction of greenhouse gases and other forms of emissions which are believed to cause climate change and known to cause acid rain, asthma, cancer and other chronic respiratory ailments in humans. Below are actual measured facts regarding the impact we have on our environment. Going Hybrid impact The same size and type of boat, running for the same number of hours at the same duty cycle using a Corvus Energy hybrid drive system emits 66 per cent less pollution. This means that 1,000 tugs equipped with Corvus hybrid drives would prevent the emission of 1.2 million tons of carbon each year. It would also prevent more than 2,800 tons of PM, 11,000 tons of NOx, and 1,100 tons of ROG. Other less publicised benefits are to the men who actually work on the boats. Reduced exposure to fumes and noise help to create a safer, healthier workplace. Carbon and NOx credits In recent years, the pollution credit markets have been evolving into the fastestgrowing commodity market in the world, with pollution credit standards evolving into tangible measurable items, with a global valuation for each type of credit produced. Credits tend to be measured in tons, with a value on each project or application being determined not only by the reduction of pollution but also such things as the integration of new technologies for the reduction of pollution. This has led to the reduction or elimination of fossil fuels as the type of project that are the most valuable and noteworthy creators of pollution credits. Organisations such as the Gold Standard in California and the Pacific Carbon Trust in British Columbia have been created to value and monetise (ie give legal value to) the reduction in pollution in credits that can be traded for values ranging from US$22 for a carbon credit to much higher values for NOx credits globally. Companies such as Lloyds and DNV have been active in qualifying the pollution credits produced for many years now. Traditional diesel Carbon dioxide (CO 2 the most well known of the greenhouse gases): One gallon of diesel fuel burned creates 10.84kg of carbon. A typical 2,000hp tug burns 163,200 gallons of diesel in a year resulting in carbon emissions of 1,769 tons. PM (Particulate Matter material suspended in the air in the form of minute solid particles or liquid droplets): The same tug under the same duty cycle will produce 4.3 tons of particulate matter in a year of use. This is one cause of lung irritation in adults and asthma in children. NOx (nitrogen oxides the leading cause of acid rain): The same tug will also produce 17.3 tons of NOx per year. ROG (Reactive Organic Gases a known cause of varied chronic health conditions): The tug in our example will also emit 1.8 tons of ROG in one year. 5 Using the information we gained from the pollution data above, the 1,000 tugs in a hybrid application would generate US$26,400, per year for the operators of these vessels. CONCLUSION In order to meet the growing demand for sophisticated vessels that are not encumbered by the limitations of current power storage technology, high quality, builtfor-purpose lithium polymer technology offers a solution that is commercially available and viable today. There are not only solid financial incentives and tools in place to make this technology viable, but performance and flexibility in use that offers a new generation of vessels the ability to exceed the needs of both their owners and the environment that commercial vessels operate within. Designers, engineers, operators and owners now all have solid reasons to transition vessels into hybrid and electric formats.

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