| 摘要 |
PROBLEM TO BE SOLVED: To reduce difference between charge rates of a plurality of battery cells connected in series, while making a charger occupation time shorter than that of conventional ones.SOLUTION: A battery system comprises: a battery module formed by connecting a plurality of battery cells in series; discharge circuits each of which is formed by connecting a switching element and a resistor in series and is provided at each battery cell; and voltage sensors for detecting voltages of the battery cells. The battery system comprises control means which, in the case of having detected a battery cell whose voltage reaches upper limit voltage from the plurality of battery cells during charge, stops the charge and discharges a battery cell whose voltage value exceeds a voltage threshold value set lower than the upper limit voltage until the value of the battery cell's voltage becomes the voltage threshold value by turning on a switching element of a discharge circuit of the battery cell. |
