Lithium ion battery, lithium ion battery negative electrode material and preparation method thereof

The invention discloses a lithium ion battery, a lithium ion battery negative electrode material and a preparation method thereof. The lithium ion battery negative electrode material comprises a composite microsphere of silicon/silicon oxide compound and graphite, an amorphous carbon layer coated on the surface of the composite microsphere and a copper layer coated outside a part of the amorphouscarbon layer. A copper-carbon double-layer coating structure is successfully constructed by coating the amorphous carbon layer on the composite microsphere of silicon/silicon oxide compound and graphite and then plating the copper layer outside the amorphous carbon layer. The copper can be used as a good conductor and can improve the electron conductance of the lithium ion battery, and the coppercan also be used as a ductile metal to provide a high-strength coating layer, effectively suppress the volume expansion of silicon, avoid the powdering of active materials such as silicon/silicon oxide compound, reduce the spe