| 摘要 |
PURPOSE: To provide a protective device, of a secondary battery, which has a protective function with reference to the degradation or the like of a battery cell block. CONSTITUTION: In a secondary battery, a plurality of battery cell blocks 1A, 1B are connected in series, and a charging FET 4 and a charging FET 5 which are composed of FETs with parasitic diodes as switching elements which can be on-off-controlled by a control circuit 6 are interposed so as to be in series with a charging and discharge route. A means which detetcs voltages of the respective battery cell blocks 1A, 1B in a charging and discharge operation and a means which controls the FETs 4, 5 so as to inhibit the charging and discharge operation when a relative voltage across the battery cell blocks 1A, 1B or its time-differentiated value exceeds a definite value are installed at the control circuit 6. |
