NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PURPOSE:To increase charge-discharge cycle life and storage performance by specifying the range of concentration of lithium hexafluorophosphate in relation to a mixed solvent consisting of ethylene carbonate and 2-methyltetrahydrofuran. CONSTITUTION:A nonaqueous electrolyte prepared by dissolving 0.1 mole/liter or more but less than 1 mole/liter of lithium hexafluorophosphate in a mixed solvent consisting of ethylene carbonate and 2-methyltetrahydrofuran is used. By the specifying of the range of concentration of lithium hexafluorophosphate serving as an electrolyte and the use of manganese dioxide or a lithium- magnanese composite oxide as a positive active material, deterioration of a lithium caused by the reaction of negative electrode lithium with the nonaqueous electrolyte and dendrite deposition can be retarded.