NEGATIVE ELECTRODE ACTIVE MATERIAL FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERIES AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY CONTAINING NEGATIVE ELECTRODE ACTIVE MATERIAL

摘要

In a nonaqueous electrolyte secondary battery in which SiOx is used as a negative electrode active material, initial charge/discharge efficiency and cycle characteristics are improved. Provided is a negative electrode active material, containing particles made of SiOx (0.5≦X≦1.5), for nonaqueous electrolyte secondary batteries. In the negative electrode active material, amorphous carbon is stuck on carbon coatings. The particles made of SiOx preferably have a size of 1 μm to 15 μm. Particles of amorphous carbon preferably have a size of 0.01 μm to 1 μm. One hundred percent of the surface of SiOx is preferably covered by the carbon coatings.

主权项

1. A negative electrode active material for nonaqueous electrolyte secondary batteries being a particulate negative electrode active material used in nonaqueous electrolyte secondary batteries, the negative electrode active material comprising:
mother particles made of SiOx (0.5≦X≦1.5); carbon coating layers each covering at least one portion of the surface of a corresponding one of the mother particles; and amorphous carbon particles stuck on the carbon coating layers.