LITHIUM ION SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery improved in electrical property such as rate characteristics and cycle characteristics by using a plurality of positive electrode active materials.

SOLUTION: When a plurality of kinds of positive electrode active materials are used, lithium insertion and elimination reaction potential of the positive electrode material of a first positive electrode layer 2a on nearer side to the positive electrode current collector 1 is made lower than that of the positive electrode material of a second positive electrode layer 2b which is farther side from the positive electrode current collector 1.

COPYRIGHT: (C)2007,JPO&INPIT