Patent ID: 8986884
Filing Date: 2015-03-24
Classification: H01M,Y02E

Abstract:
1. A lithium-ion secondary battery comprising a positive electrode and a negative electrode, wherein the positive electrode comprises, as a positive electrode active material, a lithium transition metal composite oxide having a layered structure, with the lithium transition metal composite oxide comprising at least one species of Ni, Co and Mn and further comprising W and Ca as its metal components, and the lithium transition metal composite oxide contains at least 0.26 mol % to at most 5 mol % of W and Ca combined when all the metal elements contained in the lithium transition metal composite oxide excluding lithium account for a total of 100 mol %, with the ratio (m wherein the lithium transition metal composite oxide is a lithium-containing composite oxide represented by general formula (I): wherein, x is a number that satisfies 1.05≦x≦1.25, and conditions that 0.99≦a+b+c+d+e≦1.0, at least one of a, b and c is larger than zero, both d and e are larger than zero, 0.0026≦d+e≦0.05, and 2.0≦(d/e)≦50 are all satisfied.