SECONDARY BATTERY

摘要

A secondary battery includes an electrode body. The electrode body includes a positive electrode active material layer. The positive electrode active material layer includes a plurality of hollow positive electrode active material particles, a plurality of void supporting particles, and a plurality of conductive material particles. The void supporting particles are configured to provide voids having a pore diameter of 0.5 pm or more in the positive electrode active material layer. The conductive material particles are configured to provide an electrical continuity of the positive electrode active material layer. A ratio of an average particle size of the void supporting particles to an average particle size of the hollow positive electrode active material particles is 1/3 or more and 2 or less. The crushing strength of the void supporting particles is larger than the crushing strength of the conductive material particles.