Patent ID: 6669742
Filing Date: 2003-12-30
Classification: H01M,Y02E,Y02P,Y10T

Abstract:
A method for producing a nickel metal-hydride storage battery that includes positive electrodes containing nickel hydroxide and negative electrodes containing a hydrogen-absorbing alloy, and has a nominal capacity of C (ampere-hour), the method comprising:(i) assembling a battery by enclosing the positive electrodes, the negative electrodes, separators, and an electrolyte in a case; (ii) charging the battery with electric current in a range of 0.05 C (ampere) to 0.2 C (ampere) until a state of charge rises to a range of 10% to 30%; (iii) overcharging the battery having been subjected to the charging with electric current in a range of 0.2 C (ampere) to 1 C (ampere), and thereafter discharging the same until the state of charge lowers to 10% or below; and (iv) subjecting the battery after the discharging to a plurality of charging-discharging cycles, each charging-discharging cycle being composed of charging the battery with electric current in a range of 0.2 C (ampere) to 5 C (ampere) until the state of charge rises to a range of 60% to 95%, and discharging the same until a battery voltage lowers to a range of 0.70 V to 1.05 V, wherein in the charging-discharging cycles, the battery is cooled with a coolant at a temperature in a range of 30Â° C. to 60Â° C.