| 摘要 |
PROBLEM TO BE SOLVED: To realize excellent cycle life characteristics, by detecting the closed- circuit voltage of a battery during a discharge of the battery and stopping the discharge if the voltage or the rate of change of the voltage with the lapse of time reaches or exceeds a specified value. SOLUTION: The voltage of a battery is detected during a discharge of the battery and the discharge is stopped if the voltage or the rate of change of the voltage with the lapse of time reaches or exceeds a specified value. Otherwise, during a discharge, another short-time discharge with a different current is inserted, and the voltage of the battery is measured during the short discharge period. That is, during a discharge with a current I1, another discharge with a current I2 different from the I1 is inserted by time t1, and thereafter, when the difference V2-V1 between a battery voltage V2 after the lapse of time t2 from the start of the discharge with the current I2 and a battery voltage V1 after the lapse of time t1 therefrom, exceeds a specified value, the discharge is stopped. If the short-time discharge with the current I2 different from the current I1 is not intentionally inserted, in the case of a personal computer for example, a large current flows when a hard disk is accessed, and therefore the V2-V1 can be detected also from voltage behavior appearing at that time. |
