Patent ID: 6291973
Filing Date: 2001-09-18
Classification: H02J

Abstract:
An external discharging/charging apparatus for directly charging a battery set, or first discharging and then charging the battery set, comprising at least:a DC power-supplying device for supplying power to charge the battery set;a load;a first switch, wherein when the first switch is turned on, the battery set is charged by the DC power-supplying device;a second switch, wherein when the second switch is turned on, the battery set is discharged through the load;a switch controlling device, wherein when a voltage level sensed from the battery set is higher than a predetermined value, the switch controlling device turns on the second switch, and otherwise turns on the first switch; anda charge-holding device, wherein when the voltage level sensed from the battery set after discharging is lower than the predetermined value, the switch controlling device turns off the second switch and turns on the first switch, and the charge-holding device outputs a control signal to make the switch controlling device leave the first switch in a turned-on state; and when the battery set is removed from the external discharging/charging apparatus, the control signal is eliminated such that the switch controlling device can control the first switch in response to the voltage level sensed from the battery set.