Cr, Fe and Si were added to improve the performance of olivine LiCoPO4 in cathodes for lithium-ion batteries. A substituted-LiCoPO4 in a half cell delivered a reversible capacity of 125 mAh/g at C/3 rate, with no capacity loss after over 100 cycles at 25 degrees C. The well-known capacity fade of LiCoPO4-based cathodes was almost completely eliminated by substituting Cr, Fe and Si.