LI/LIXNIO2 AND LI/LIXCOO2 RECHARGEABLE SYSTEMS - COMPARATIVE-STUDY AND PERFORMANCE OF PRACTICAL CELLS

Lithiated cobalt and nickel oxides have been prepared using an original synthesis process, based on thermal treatment with LiOH. Their properties as reversible cathodic material for lithium rechargeable cell were studied, showing different behavior in electrochemical mechanisms. Excellent energy densities were obtained from the two compounds. At high working potential from 4 to 3 V, up to 300 W h/l and 174 W h/kg were obtained in 'C'-size cells. The kinetics of cathode reactions are fairly rapid, which allows high rate of discharge (> 'C'). Cycle life was demonstrated over more than 100 cycles. Storage capability was tested at 45-degrees-C at the charged state. Better results were obtained with LixNiO2 than with LixCoO2.