| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery of excellent charge and discharge cycles by using the mixed solvent among at least one kind selected from dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate, and propylene carbonate, and 1,4-dioxane for an aqueous solvent. SOLUTION: For a nonaqueous electrolyte secondary battery, a separator 5 is interposed between a positive electrode 1 and a negative electrode 2, and insulators 9 and 10 are arranged above and below an electrode body, and they are accommodated in a batter container 6, and a negative lead terminal 4 is connected to the bottom of the vessel, and a positive electrode lead terminal 3 is connected to the sealing board 7 of the battery. The hydrolytic solvent is the mixed solvent among at least one kind selected from dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate, and propylene carbonate, and 1,4-dioxane. The mixture ratio of 1,4-dioxane in the nonaqueous solvent is 0.1-5 volume %, and the mixture ratio of propylene carbonate is 30-60 volume %. Even in case that it is used with charge potential of 4V or over, excellent charge-discharge cycle can be obtained. |
