摘要 |
A battery pack that detects the voltage of a plurality of batteries ( 1 ) connected in series with a plurality of voltage detection circuits ( 2 ). When a voltage detection circuit output is HIGH, batteries ( 1 ) discharge through an output resistor ( 6 ). In addition, discharge circuits ( 7 ), which are series connections of balance resistors ( 8 ) and switching devices ( 9 ), are connected in parallel with batteries ( 1 ) left "un-discharged" by the output resistors ( 6 ). When a voltage detection circuit output is HIGH, some batteries ( 1 ) are discharged by the output resistor ( 6 ) and the "un-discharged" batteries ( 1 ) are discharged by the discharge circuit ( 7 ). When a voltage detection circuit output is LOW, no batteries ( 1 ) are discharged by the output resistor ( 6 ) and the "un-discharged" batteries ( 1 ) are also left un-discharged by the discharge circuit ( 7 ) to balance the discharge currents of all the batteries ( 1 ). |