Patent ID: 6998194
Filing Date: 2006-02-14
Classification: H01M,Y02E

Abstract:
1. A nonaqueous electrolyte secondary battery, comprising: a case; an electrode group comprising a positive electrode, and a negative electrode which is provided in the case; and a nonaqueous electrolyte which is provided in the case and comprises a nonaqueous solvent, wherein the nonaqueous solvent comprises ethylene carbonate (EC), propylene carbonate (PC), γ-butyrolactone (GBL), vinylene carbonate (VC) and a fifth component that comprises vinyl ethylene carbonate and/or phenyl ethylene carbonate and the nonaqueous solvent satisfies the following relationships (5) to (9): where, x is the ratio (volume %) of ethylene carbonate to the total volume of the nonaqueous solvent, y is the ratio (volume %) of propylene carbonate to the total volume of the nonaqueous solvent, z is the ratio (volume %) of γ-butyrolactone to the total volume of the nonaqueous solvent, w is the ratio (volume %) of vinylene carbonate to the total volume of the nonaqueous solvent, and q is the ratio (volume %) of the fifth component to the total volume of the nonaqueous solvent.