METHOD FOR RECOVERING CAPACITY OF ALKALINE RECHARGEABLE BATTERY

To provide a capacity recovery method of a nickel hydride storage battery, which recovers a capacity of a positive electrode while avoiding deterioration of an output due to an open valve.SOLUTION: A capacity recovery method of a nickel hydroxide storage battery, includes: a positive electrode that contains an active material using a charging and discharging device and a control device for controlling them, and having a nickel hydroxide as a main component; and an electrolyte containing a potassium hydroxide aqueous solution. A recover charing of the nickel hydroxide storage battery, comprises: an order of a high rate charging (S43) that performs a charging at a charging rate higher than that of a low rate charging (S41) in a low SOC region as a SOC lower than the lowest length SOC in a high SOC region as C in a region of the SOC higher than the lowest length as the SOC of an alkaline secondary battery of which a c axis length of the nickel hydroxide becomes the shortest; and a high rate discharge (S45). A type of an alkali ion such as a potassium ion (K+) fetched into the positive electrode is discharged to recover a capacity of the positive electrode by diffusing a proton (H+) into the positive electrode.SELECTED DRAWING: Figure 10