RECHARGEABLE CATHODES BASED ON LI2CRXMN2-XO4

Phases in the solid-state solution series Li2CrxMn2-xO4 were prepared as single-phase compounds over the range 0<x<2. The unit cell volume d ecreases smoothly with increasing chromium content as Cr3+, With a sma ller ionic radius, is substituted for Mn3+. The X-ray powder diffracti on patterns of phases in the range 1.5 less than or equal to x<2 are s imilar to that of LiCrO2, while the diffraction patterns of Li2CrxMn2- xO4 phases over the range 0<x less than or equal to 1.25 resemble that of lambda-Li2Mn2O4. Selected phases of Li2Cr(x)Mn(2-x)O(4) were forme d into cathodes and evaluated in lithium-ion cells with petroleum coke -based anodes.