Battery protection switch

The utility model discloses a battery protection switch, include battery, current sensor, quick electronic switch, relay and the pullup resistor of series connection, it has overcurrent protect device to connect in parallel between current sensor and the quick electronic switch, and it has microprocessor to connect in parallel between current sensor, quick electronic switch and the relay, and overcurrent protect device is connected with the microprocessor electricity. The beneficial effects of the utility model are that: when battery protection switch guarantees that the relay switches over, not having the electric current in the system return circuit, converting a relay area year switching life-span into machinery and switch over the life-span, it is area year more than 10 times of life-span of switching that general relay machinery switches over the life-span, has improved the life of relay greatly, avoids simultaneously overflowing and damages quick electronic switch, has promoted battery protection switch's reliability by a wide margin.