ACTIVE MATERIAL PARTICLES, ELECTROCHEMICAL ELEMENT, METHOD FOR PRODUCING SAID ACTIVE MATERIAL PARTICLES, METHOD FOR PRODUCING SAID ELECTROCHEMICAL ELEMENT, AND ELECTROCHEMICAL DEVICE

摘要

Each one of the active material particles according to the present invention is provided with: a lithium silicate composite particle that contains a lithium silicate phase and silicon particles dispersed in the lithium silicate phase; and a first coating film that covers at least a part of the surface of the lithium silicate composite particle. The first coating film contains carbon atoms and an oxide of a first element that is other than a non-metallic element; and if T1_A is the thickness of the first coating film, the element ratio Rb of the first element to the carbon atoms of the first coating film at the position of 0.25T1_A from the surface of the lithium silicate composite particle and the element ratio Rt of the first element to the carbon atoms of the first coating film at the position of 0.75T1_A from the surface of the lithium silicate composite particle satisfy Rb > Rt.