Battery heat exchanger, battery pack, thermal management system and vehicle

The utility model discloses a battery heat exchanger, a battery pack, a heat management system and a vehicle. The battery heat exchanger comprises a heat exchange plate, a first collecting pipe and a second collecting pipe, the heat exchange plate is provided with micro-channels which are spaced in the width direction of the heat exchange plate, and each micro-channel penetrates through the heat exchange plate in the length direction of the heat exchange plate; the first collecting pipe and the second collecting pipe are arranged at the two ends, in the length direction, of the heat exchange plate correspondingly and extend in the width direction of the heat exchange plate, and the two ends, in the length direction, of each micro-channel on the heat exchange plate communicate with the first collecting pipe and the second collecting pipe correspondingly. According to the battery heat exchanger, the flow channel is in the one-way trend, the on-way length of a cooling medium in the heat exchange plate is effecti