High energy rechargeable lithium batteries would be of great importance for the entire field of heart pump development and other implantable or portable medical or biomedical devices, providing energy densities well in excess of what nickel-cadmium batteries deliver at present. It is proposed to emphasize an innovative approach in which exceptionally high energy density reducible cathodes capable of high discharge rates are employed with high conductivity electrolytes designed using a multicomponent cosolvent formulation. Recent laboratory results have demonstrated a good cycling capability for a high energy divalent metal halide-Li system. The remarkably high energy density of the proposed Li- reducible cathode battery system results in a projection of a small, light weight VAS internal battery with an energy density 3- 4 x greater than Hi-Cd. and yet able to provide over 100 mins.of operating time, compared to 15-30 mins for current designs. Experimental laboratory cells containing reducible cathodes comprised of metal halides would be evaluated for discharge capacity. high rate performance. and cycle life. Design of separator systems for long cycle life. and a viable overcharge mechanism would lead into the construction of sealed cylindrical cells. These prototype cells would be extensively evaluated for discharge rate capability and cycle life. In addition, safety tests will be conducted.
