HIGH PERFORMANCE CATHODE FOR LITHIUM-ION BATTERIES

Sony Corporation's recent large scale commercialization of the lithium-ion battery for cellular phones has shown this system to be inherently safe, with high cycle life (1200 cycles), specific energy and energy density (83+ W.hr/kg). This application demonstrates the ideal suitability of the lithium-ion battery for both space and portable electronics applications. PolyStor Corporation personnel have previously developed a high capacity carbon foam anode tehcnology (used in all "potential" lithium ion system couples) which has reached the theoretical capacity limit (372 mA.hr/gm carbon, compared to Sony's 206 mA.hr/gm). The best present high voltage cathode technology is expensive to produce asnd has a useful capacity of about one third of this value (125mA.hr/gm, high temperature LiCo02) and is therefore not well matched to the anode. Improvements in the cathode specific capacity and manufacturability provide the best means to substantially improve battery performance.