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

An active material particle include a lithium silicate composite particle including a lithium silicate phase, and silicon particles dispersed in the lithium silicate phase, and a first coating that covers at least a portion of a surface of the lithium silicate composite particle; wherein the first coating includes an oxide of a first element other than a non-metal element, and a carbon atom, the first coating has a thickness T1, an element ratio Rb of the first element relative to the carbon atom at a position of 0.25T1of the first coating from the surface of the lithium silicate composite particle, and an element ratio Rt of the first element relative to the carbon atom at a position of 0.75T1of the first coating from the surface of the lithium silicate composite particle satisfy Rb>Rt.