NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

The purpose of the present invention is to provide a nonaqueous electrolyte secondary battery which has excellent battery characteristics, while having an SEI coating film that has a special structure. An electrolyte solution which contains an organic solvent having a hetero element and a salt wherein an alkali metal, an alkaline earth metal or aluminum serves as cations, and which satisfies Is > Io is used as the electrolyte solution of the nonaqueous electrolyte secondary battery of the present invention, and a coating film containing S and O and having an S=O structure is formed on the surface of the positive electrode and/or the surface of the negative electrode. Alternatively, the above-described electrolyte solution is used in the nonaqueous electrolyte secondary battery of the present invention, and a binder that is composed of a polymer having a hydrophilic group is used as a binder for the negative electrode.