| 摘要 |
PROBLEM TO BE SOLVED: To provide a polymer electrolyte which has a good electrolyte solution holding property and excellent high temperature characteristics, and to provide a nonaqueous electrolyte secondary battery. SOLUTION: A copolymer, which is formed by copolymerizing a mixture including a vinylidene fluoride monomer, a tetrafluoroethylene monomer, and a hexafluoropropylene monomer, is used as a polymer material composing the polymer electrolyte. The copolymer is characterized in that the ratio of the tetrafluoroethylene unit is not less than 5 wt.% and below 30 wt.%. Alternatively, the copolymer is characterized in that the ratio of the hexafluoropropylene unit is not more than 10 wt.%. As a result, the polymer electrolyte, which has the good electrolyte solution holding property and the excellent high temperature characteristics, and the nonaqueous electrolyte secondary battery can be provided. COPYRIGHT: (C)2003,JPO |
