ACTIVE MATERIAL, ELECTRODE, BATTERY CELL, LITHIUM ION SECONDARY BATTERY AND ELECTRONIC DEVICE

摘要

PROBLEM TO BE SOLVED: To provide: a lithium ion secondary battery with a large capacity; or a lithium ion secondary battery enhanced in cycle characteristics.SOLUTION: An active material comprises: particles having lithium, manganese, oxygen and nickel. The particles have a layered rock salt type crystal structure region. The crystal region has a lamination defect. Using an electrode including as an active material, a material having a lamination defect in its layered rock salt type crystal structure region for a lithium ion secondary battery enables the increase in discharge capacity, and the enhancement of battery cycle characteristics involved with charge and discharge thereof.SELECTED DRAWING: Figure 1