| abstract |
A method for producing a material capable of electrochemically storing or releasing a large amount of lithium ions is provided. The primary particles of silicon or tin are composed of crystal particles having a diameter of 5 nm to 200 nm with an amorphous surface layer having a thickness of 1 nm to 10 nm, and the amorphous surface layer of the primary particles is composed of at least a metal oxide. The Gibbs free energy when the metal oxide is generated by oxidation of the metal is smaller than the Gibbs free energy when the silicon or tin is oxidized, and the metal than the silicon oxide or tin oxide. Electrode material for negative electrode of electricity storage device that can store and release lithium ions electrochemically where oxide is thermodynamically stable. [Selection] Figure 1 |