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At the end of 2007 SAFT developed the next generation of power Lithium Ion and delivered first prototypes. This work is funded by US Army TACOM and is continuation of US Air Force AFRL sponsored effort aimed at meeting the needs of both aircraft power as well as emerging Directed Energy applications. Ultra High Power (UHP) Li-ion cells offer unparalleled continuous and pulse power. Additionally the technology is capable of excellent charge acceptance and power delivery at low temperature. These specific characteristics could enable a floating on the bus aviation battery in the near future. The extreme pulse power capability coupled with limited heat generation make the technology a leading candidate for a Directed Energy intermediate energy storage power system.

The AFRL, Electrochemistry and Thermal Sciences Branch has evaluated numerous aircraft battery designs and chemistries since the 1960s. Recent experiments on advanced battery chemistries have shown poor performance at ultra low temperatures below −20° C. Aircraft battery designs stress low weight and volume and maximum capacity. One design concept uses lower capacity cells in a series parallel configuration to reduce overall battery resistance and should also improve ultra low temperature performance. Our organization has begun experiments with series-parallel cell designs to evaluate the concept and to solve low temperature performance issues. Progress, observations on the effect of different chemistries, and the impact on aircraft battery characteristics are discussed.