LIMN2-XCOXO4 CATHODE WITH ENHANCED CYCLEABILITY

Lithium-manganese-cobalt oxides, LiMn2-xCoxO2 with 0<x<0.2 were synthe sized by a solid-state multi-steep reaction, in air, from a mixed mang anese-cobalt oxide with lithium hydroxide, The samples were characteri zed by X-ray diffraction and electrochemical tests. The crystal struct ure of the obtained compounds is spinel-related. The discharge capacit y of an Li/LiMn2-xCoxO2 cell with x = 0.1 was 114 mAh/g for the fifth discharge and staged almost the same at the cycle no, 100-107 mAh/g - related to the cathode capacity. The demonstrated cycling stability fo r 100 cycles reaches 99.93%, The improvement in cycleability can be at tributed to the stabilizing role of Co3+ ions, substituting Mn3+ in th e initial structure. (C) 1997 Published by Elsevier Science S.A.