Patent ID: 7510804
Filing Date: 2009-03-31
Classification: H01M,Y02E

Abstract:
1. A cathode material for use in a lithium secondary battery comprising a compound represented by the chemical formula: Li x Ni y Co z M m O 2 when not in a charged state, having high thermal stability and large discharging capacity in which M is selected from the group consisting of Ba and Ba with Sr, and x, y, z and m are values for the molar ratio of each element: 0.9≦x≦1.1, 0.5≦y≦0.95, 0.05≦z≦0.5 and 0.0005≦m≦0.005, wherein the compound represented by the chemical formula: Li x Ni y Co z M m O 2 when not in a charged state changes to a compound when in a charged state represented by the chemical formula: Li a Ni b Co c M n O 2 and a, b, c and n are values for the molar ratio of each element and are, respectively, 0.2≦a≦0.4, 0.5≦b≦0.95, 0.05≦c≦0.5, and 0.0005≦n≦0.005 and the material is powdery, has a BET specific surface area 0.8 m 2 /g or less and has a DTG increase start temperature at 215° C. or higher.