A High Power Bipolar Ni-MH Battery for a Hybrid Vehicle

40290 November 6, 1996 Electro Energy, Inc. Advanced batteries are a critical component for hybrid electric vehicles (HEVs). In a power assist mode, the battery is mated with a small internal combustion engine so that the battery can assist with acceleration as well as recover spent energy through regenerative braking. Such a role requires that the battery have high energy and power density, offer exceptionally long cycle life, meet demanding cost objectives, and be safe and ecologically sound. No presently available battery system is capable of meeting this mix of attributes, especially the anticipated power densities of l,000 W/kg. This project will develop a new approach to a stackable wafer cell-type bipolar design which has already been shown to offer performance improvements over conventional Ni-MH batteries in energy and power density, as well as in cycle life and cost. The new design is expected to enable bipolar operation in a much higher power regime than previously possible. Phase I will concentrate on component development, including the electrode compositions, as well as on separator and cell interface. Anticipated Results/Potential Commercial Applications as described by the awardee: This project should result in new opportunities for portable or motive devices requiring high power and energy density batteries. Applications include power tools, cordless lawn mowers, electric and hybrid cars, and other motive applications.