| 摘要 |
PURPOSE:To prevent dendrite short and restrain negative electrode deterioration while extending cycle lifetime and enlarging discharge capacity by adding a carboxyl compound to a water solution of zinc sulfate as an electrolyte. CONSTITUTION:A carboxyl compound is added to a water solution of zinc sulfate as an electrolyte. As a compound for discharging carboxyl anion, there are used, for example, sodium acetate, zinc acetate, zinc formic acid and the like. Any amount of the carboxyl compound may be added, but preferably is within 0.1mM to 1M in order to keep low electronic conductivity and the reversibility of a positive electrode material. The addition of the carboxyl compound has an effect on the pH value of the electrolyte via carboxyl anion contained therein. Also, an influence is caused on nucleation when zinc is deposited on a negative electrode. Furthermore, the roughening of crystal grains due to the progress of a cycle is restrained. Therefore, dendrite short is thereby prevented. |
