Abstract: The present disclosure relates to a cover plate assembly for a lithium ion battery and a lithium ion battery. The cover plate assembly includes a cover plate body, provided at a middle portion thereof with a through hole which extends to form a tube body, and the tube body protrudes from at least one surface of the cover plate body; a pressure relief portion, wherein the pressure relief portion is located in the tube body and is in sealed communication with the tube body, the pressure relief portion is ring-shaped and is configured to crack and split from the cover plate body in response to deformation of the cover plate body; and a central conductor, embraced by the pressure relief portion and runs through the pressure relief portion along the axial direction. The cover plate assembly features excellent safety performance and small space occupation.

Abstract: The present disclosure discloses an explosion-proof enclosure for an energy storage device and an energy storage device. The explosion-proof enclosure includes: a housing body, having a through hole; and an explosion-proof element, including a central portion and a pressure relief portion provided around the central portion, wherein the pressure relief portion is loop-shaped, the pressure relief portion is provided in the through hole and is in sealed connection with the through hole, the pressure relief portion is configured to crack and split from the housing body in response to the deformation of the housing body when the pressure intensity in the housing body reaches a first set value, and to detach from the housing body when the pressure intensity reaches a second set value, wherein the second set value is greater than the first set value.