Patent ID: 8541136

Claim:
A positive electrode material having an improved charge capacity at high discharge rates, the positive electrode material comprising: an electroactive material having two or more phases comprising lithium (Li), an electroactive metal (M), and phosphate (PO 4 ), wherein the overall composition of the electroactive material has a ratio of Li:M ranging from greater than 1.1 to about 1.3, a ratio of (PO 4 ):M ranging from about 1.0 to about 1.14, the ratios Li:M and (PO 4 ):M are as compared to a stoichiometric composition for an olivine lithium transition metal phosphate (LiMPO 4 ), M is one or more metals selected from the group consisting of Cr, Mn, Fe, Co, and Ni, and wherein the electroactive material comprises an olivine lithium electroactive metal phosphate phase and less than 10 wt % of a lithium-rich secondary phase or a lithium-rich and phosphate-rich secondary phase.