Patent ID: 7928695

Claim:
A rechargeable battery protection device, comprising, a voltage detector for detecting voltages of a first terminal and a second terminal of a rechargeable battery; a logic circuit linked to the voltage detector for outputting a first voltage equal to the voltage of the first terminal of the rechargeable battery and a second voltage equal to the voltage of the second terminal of the rechargeable battery; an output stage coupled to the first and the second terminals of the rechargeable battery for receiving the first voltage from the logic circuit and converting the first voltage into a third voltage; a first switch linked to the second terminal of the rechargeable battery and the logic circuit for receiving the second voltage from the logic circuit for switching on a current path from a first terminal of a charger to a second terminal of the charger when a voltage difference between the first terminal of the rechargeable battery and the second terminal of the rechargeable battery is close to 0V; a second switch linked to the second terminal of the charger and connected in series with the first switch for switching on the current path from the first terminal of the charger to the second terminal of the charger when the voltage difference between the first terminal of the rechargeable battery and the second terminal of the rechargeable battery is close to 0V; and at least two inverter circuits linked to the output stage, the second switch and the first terminal of the rechargeable battery for receiving the third voltage from the output stage and outputting a fourth voltage to the second switch and a fifth voltage to the charger.