| 摘要 |
PURPOSE:To mitigate a drop of a capacity after maintenance and lengthen an interval of maintenance by setting an operating pressure of a valve for use in maintenance lower than an operating pressure of a safety valve during an electric charging/discharging cycle for the purpose of overcharging. CONSTITUTION:An operating pressure for use in maintenance is set lower than an operating pressure of a conventional valve, i.e., an operating pressure (3atm or higher) of a safety valve, more preferably set to 1.5-2.5atm, followed by overcharging (releasing overcharging). Although a battery capacity of the positive electrode, which is reduced after maintenance by the electric overcharging, is recovered from M2 to M1, an extra capacity S is generated in the negative electrode at the time of electric charging after maintenance. Consequently, electric charging is principally dependent on the positive electrode until hydrogen is completely stored in the extra capacity S. As a result, it is possible to mitigate a drop of the capacity after maintenance and lengthen an interval of maintenance. |
