NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PURPOSE:To provide a nonaqueous electrolyte secondary battery which is excellent at cycle life characteristic and low temperature characteristics by improving the solvent of electrolyte. CONSTITUTION:A nonaqueous electrolyte secondary battery includes a negative electrode 3 made by a carbonaceous material which can store and release lithium ions, nonaqueous electrolyte, and a positive electrode 1 made by an oxide containing lithium. The solvent of the nonaqueous electrolyte is a mixed solvent of ethylene carbonate and propionic acid methyl. The ratio of the volume of the propionic acid methyl to that of the ethylene carbonate is not less than 1 and not more than 4. The nonaqueous electrolyte secondary battery excellent in cycle life and low temperature characteristics is thus obtained.