Shell structure of square steel shell lithium battery

The utility model relates to a square steel shell lithium battery shell structure. The square steel shell lithium battery shell structure comprises a front shell and a rear cover plate welded with the front shell, a liquid injection hole is formed in the front shell, and an anti-explosion piece is welded to the liquid injection hole. According to the utility model, the structure is reasonable, the design is novel, and a pressure relief point is formed at the position of the liquid injection hole, so that high-pressure air pressure is enabled to burst away from the pressure relief point preferentially to release pressure when abnormities such as short circuit and the like in a battery cell are ensured, and the problem that people and equipment are injured due to explosion caused by the fact that the pressure in the steel shell rises all the time is prevented; the structure is good in safety performance, and the safety performance of the square steel shell lithium ion battery in emergencies such as short circui