| 摘要 |
PROBLEM TO BE SOLVED: To enable abnormality (fault) in a current detection unit to be determined without providing two detection circuits in the current detection unit for detecting a battery current in an electric-powered apparatus system.SOLUTION: An abnormality determination unit 48 of a battery pack 2 estimates, upon discharging from a battery 10 to an electric-powered tool 50 and charging to the battery 10, battery voltage and battery temperature change amounts from a battery current (a discharge current or a charge current) obtained by a detection signal from a current detection circuit 26, and, when one of differences between the estimation results (estimate voltage change amount and estimate temperature change amount) and actual battery voltage and battery temperature change amounts obtained from a cell voltage measurement IC 20 and a temperature detection circuit 22 exceeds a default value, determines that a current detection unit comprising a current detection resistor 24 and the current detection circuit 26 is abnormal. |
