摘要 |
PURPOSE:To increase the conductivity of an electrolyte and the chargedischarge efficiency of a lithium electrode by containing a specified concentration range of dicarboxylic acid compound as an additive. CONSTITUTION:A dicarboxylic acid compound is contained in a concentration range of 10<-3>-10<-1>M (mole/l) in an electrolyte. The dicarboxylic acid compound used is a compound having two carboxyl group. Monoester or diester obtained by substituting alkyl group, phenyl group, benzyl group, or derivative of each of these for one or two hydrogen atoms of the carboxyl group is used, however a compound obtained by substituting alkali metal or alkali earth metal also has similar effect. A group to be bonded to the carboxyl group of the dicarboxylic acid compound is either aromatic group or nonaromatic group. The conductivity of an electrolyte and the charge-discharge performance of a lithium electrode are increased. |