PRESSURE RELIEF VALVE FOR BATTERY PACK AND BATTERY PACK

A pressure relief valve includes a valve body; a valve cover matched with the valve body; a flexible element positioned between the valve body and the valve cover and having a through hole; and a breathable film covering the through hole. The flexible element has a compression portion at least partially surrounding the through hole and configured to be deformable to make the flexible element displace relative to the valve body. A battery pack can use the pressure relief valve. Due to the use of the pressure relief valve, internal pressure of the battery pack can be controlled.