ALL SOLID LITHIUM ION SECONDARY BATTERY

摘要

Provided is an all solid lithium ion secondary battery. The all solid lithium ion secondary battery has a positive electrode active material particle and a positive electrode including a solid electrolyte particle which comes into contact with the positive electrode active material particle, wherein the positive electrode active material particle comprises: a lithium cobalt oxide particle; a first coating layer which includes a nickel element, and covers at least one portion of the lithium cobalt oxide particle; and an M1 element, and a composition of the positive electrode active material particle is represented by chemical formula 1. The average diameter of the positive electrode active material particle has 5 to 35 μm. The all solid lithium ion secondary battery can improve discharge capacity and cycle properties.