NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To preserve lithium to be reversibly doped/undoped in a carbonic material serving as a negative electrode active material under an over- discharged state so as to provide a nonaqueous electrolyte secondary battery with little battery characteristic change after over-discharging by means of a simple safe means by using a proper carbonic material as the negative electrode active material. SOLUTION: A non-aqueous electrolyte secondary battery is provided with a negative electrode using a carbonic material, to/from which lithium can be doped/undoped, as a negative electrode active material, a positive electrode using a lithium transition metal composite oxide as a positive electrode active material, and a non-aqueous electrolyte prepared by dissolving lithium salt in an organic solvent. The carbonic material includes a high residual capacity carbonic material allowing reversibly charge/discharge at 20 mAh/g or more per a unit weight within a potential range from 0.5 V to 1.0 V when an electrode potential of metallic lithium is set to 0 V.