PRESSURE RELIEF APPARATUS, BATTERY CELL, BATTERY AND ELECTRICAL DEVICE

The embodiments of the present application provide a pressure relief apparatus, a battery cell, a battery, and an electrical device, which belong to the technical field of batteries. The pressure relief apparatus comprises a pressure relief part and multi-stage score grooves, wherein the pressure relief part has a first surface and a second surface in a thickness direction thereof that are opposite to each other; and the multi-stage score grooves are sequentially arranged on the pressure relief part in a direction from the first surface to the second surface, wherein among two adjacent stages of score grooves in the thickness direction, the stage of score groove far from the first surface is arranged on the bottom surface of the stage of score groove near the first surface. The pressure relief apparatus of this structure adopts the structure of multi-stage score grooves, which can reduce the forming depth of each stage of score groove, thereby reducing the forming force applied to the pressure relief part when each stage of score groove is formed, and reducing the risk of cracks generated on the pressure relief part, so that the pressure relief apparatus is not easy to fail due to cracks generated on the pressure relief part at the position where the score grooves are arranged, thus improving the long-term reliability of the pressure relief apparatus.