Applications advanced battery systems

As of this writing, there is little commercialization of advanced battery systems. Small rechargeable lithium button cells have been commercialized, however, by Sanyo, Matsushita (Panasonic), and Toshiba. These cells are intended for original equipment manufacturer (OEM) use in applications such as memory backup and are not available to the general consumer. 

Another conventional battery technology that has been considered for EVs is Ni/Cd. Although capable of somewhat better performance than lead-acid in some respects, this battery is also more costly and does not equal the performance levels possible with advanced battery systems. It is unlikely to see widespread use in EV applications in the U.S. although there are reported to be more than 10,000 EVs using Ni/Cd batteries presently on the road in Europe [23]. Because of the toxicity of cadmium, which precludes disposal, and the value of the nickel, there are well-developed processes for recycling of Ni/Cd batteries. Most of the facilities in Europe are dedicated Ni/Cd battery recycling plants. 

Much of the effort to develop the Na/S battery was aimed at its use in electric vehicles. Current applications of this advanced battery system are now mainly in the stationary battery area, but feasibility studies were done on the recycling of this system before the EV development efforts were suspended. Sodium/sulfur batteries contain reactive and corrosive materials, but not toxic ones. By treatment of the battery waste, the reactivity problems can be removed. 

Thermal aspects of batteries and their consequences on automotive applications can be briefly reminded here. In general, it would be easy to imagine that heat losses in advanced battery systems could be great. The maximum output power typically reaches more than several kilowatts. If we assume that the energy efficiency of a battery is 90% in these cases, there is a deficit of 10% due to the loss of energy as heat within the battery. 

Several test facilities are in existence in the U.S. for the evaluation of improved and advanced battery systems. Batteries of all types are tested at Argonne National Laboratory, Idaho National Engineering Laboratory, Lawrence Berkeley National Laboratory, and Sandia National Laboratories. Certain tests for satellite and military applications are conducted at the Naval Surface Warfare Center in Crane, Ind. There are also specialized testing facilities established by companies in the private sector and test facilities in other countries. 

Portable power applications continue to drive research and development of advanced battery systems. Often, the extra energy content and considerations of portability have outweighed economics when a system is considered. This has been true of lithium battery technologies for the past thirty years and for lithium ion battery systems, which evolved from the early lithium battery development hi recent years, the need for portable power has accelerated due to the miniaturization of electronic pliances where in some cases the battery system is as much as half the weight and volume of the powered device. 

S. Voss, H. Kollmann, and W. Kollmann. New innovative materials for advanced electrochemical applications in battery and fuel cell systems. Journal of Power Sources 127 (2004) 93-97. 

The above discussion provides the context for 3-D batteries. That is, there are a variety of small power applications, typified by MEMS devices, which the most advanced, 2-D lithium battery systems are unable to satisfy. The inability to provide sufficient power is because of configuration and not because of intrinsic energy density. Three-dimensional designs offer the opportunity to achieve milliwatt-hour energies in cubic millimeter packages and, more importantly, with square millimeter footprints. While such power sources may not influence the enormous commercial markets in cell phones and laptop computers, they are certain to impact emerging markets where... 

R. S. Gordon, W. Fischer, A, V, Virkar, in Ceramic Transactions Vol. 65, Role of Ceramics in Advanced Electrochemical Systems, P. N. Kumpta, G. S. Roher, U. Balachadran, eds., American Ceramic Society, Westerville, OH, 1996, pp. 203-237. Current review on the application of ceramics in the sodium sulfur battery and the solid oxide fuel cell. 

Lithium-ion [71-73] and lithium-ion polymer batteries [74] are commodity products in consumer applications, but are not yet ready for use in the harsh automotive environment. Although in an advanced state of development, the batteries are not expected to be ready for mass production for use in automotive applications in the near future. If limitations in calendar life at elevated temperature can be overcome and production costs can be lowered to an acceptable level, the lithium-ion battery may become a serious competitor to both AGM lead-acid and Ni-MH batteries, as the lithium-ion system combines the strengths of both these battery systems. 

Lithium-ion batteries have been commercially available for over 2 decades and currently represent state-of-the-art power source for all modem consumer electronic devices. Due to its advanced chemistry, Li-ion cells exhibit superior performance characteristics over most other rechargeable battery systems. The lithium-ion technology offers a high energy and power density, long life, and reliability that makes it attractive for electric drive vehicle (EDV), military, and aerospace fields, and large format Li-ion cells and battery packs are currently under development for such applications. 

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