摘要 |
PURPOSE: To prevent oxidative deterioration of an electrode active material without lowering appearance capacity in a cell containing a proton transmission type polymer as an active material to improve cycle properties. CONSTITUTION: An electrolyte with a water-soluble N-containing heterocyclic compound added into an aqueous solution of an organic or inorganic acid is used. Examples of the N-containing heterocyclic compound include imidazole and derivatives thereof represented by the formula (1), triazole and derivatives thereof represented by the formula (2) or (3), and pyrazole and derivatives thereof represented by the formula (2). In the formulae, substituents R are, independently of one another, an H atom, an alkyl group with carbon number of 1 to 4, amino group, carboxyl group, nitro group, phenyl group, vinyl group, halogen atom, acyl group, cyano group, trifluoromethyl group, alkylsulfonyl group or trifluoromethylthio group. |