US Patent 7132199 Non-aqueous electrolyte and non-aqueous electrolyte secondary battery

A non-aqueous electrolyte containing propylene carbonate and 1,3-propanesultone as additives can reduce the amount of a gas evolved during storage at a high temperature of a non-aqueous electrolyte secondary cell comprising the electrolyte, a non-aqueous electrolyte containing at least one compound selected from the group consisting of vinylene carbonate, diphenyl disulfide, di-p-tolydisulfide and bis(4-methoxyphenyl)disulfide as comprising the electrolyte, and a non-aqueous electrolyte containing a combination of the above-two types of additives can provide a non-aqueous electrolyte secondary cell exhibiting excellent retention of capacity and storage stability.