The utility model relates to the technical field of batteries, and discloses a cover plate structure and a
battery cell, the cover plate structure comprises: a plate body provided with an explosion-proof valve hole and a
liquid injection hole, the explosion-proof valve hole and the
liquid injection hole being arranged at an interval; the protection piece covers the anti-explosion valve hole, a
helium detection opening is formed in the protection piece, the
helium detection opening is located in the side, away from the
liquid injection hole, of the protection piece, and at least part of the
helium detection opening is overlapped with the projection of the anti-explosion valve hole in the direction perpendicular to the plate body; the circumferential edge of the side, facing the plate body, of the protection piece is coated with a bonding layer, the bonding layer and the edge, surrounding the anti-explosion valve hole, of the plate body are bonded, and an avoiding area is formed in the area, close to the helium detection opening, of the bonding layer. According to the cover plate structure provided by the utility model, the helium detection port can be far away from the liquid injection hole, and the difficulty that
electrolyte overflowing from the liquid injection hole flows to the helium detection port and enters the surface of the anti-explosion valve is increased, so that the risk that the
electrolyte enters the surface of the anti-explosion valve through a protection sheet to pollute the anti-explosion valve is reduced.