NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

Provided is a non-aqueous electrolyte secondary battery containing amorphous carbon as the base of a negative-electrode active material and having high energy density, small loss of capacity when stored in charged state, and excellent cycle life characteristics. The secondary battery is provided with a negative-electrode active material that is a mixture of graphitizable carbon, non-graphitizable carbon, and graphite, said negative-electrode active material being composed of graphite and composite particles having a structure in which non-graphitizable carbon is bonded to particle surfaces of graphitizable carbon. In particular, the non-graphitizable carbon content is preferably 0.5 to 7% of the total weight of the mixture, the graphite content is preferably 5 to 20% of the total weight of the mixture, and the non-graphitizable carbon is preferably provided on the particle surfaces of the graphitizable carbon by a mechanochemical treatment.