| abstract |
PURPOSE:To improve charge and discharge characteristics in a high temperature atmosphere without impairing the performance which it had by using 1,2- diethoxyethane instead of DME (1,2-dimethoxyethane). CONSTITUTION:An electrolytic solution is a mixed solvent which consists of one or two kinds out of propylene cabonate and gamma-butyrolacton, and 1,2- diethoxyethane. Because 1,2-diethoxyethane (DEE) has almost the same structure as that of DME, the chemical properties are also likely to those of DME and DEE shows quite the same behavior as that of DME in the mixed solvent. Among physical properties, their dielectric constants are almost the same, and the viscosity of DEE is lower, so that the characteristics (for example, heavy load discharge characteristics etc.) of a conventional device are not degraded by using DEE. Moreover, the boiling point of DEE is higher than that of DME, thereby the stability in a high temperature atmosphere is improved and the charge and discharge characteristics in a high temperature atmosphere is also improved. |