Terminal, top cover structure, battery cell, battery module, and battery pack

A top cover structure, comprising a terminal, the terminal comprising a first metal part and a second metal part connected to each other, a protruding portion being arranged at an end of one of the first metal part and the second metal part, a first recessed portion being arranged at an end of another one of the first metal part and the second metal part, the protruding portion being connected to the first recessed portion in an embedded manner;

• an edge of an end, close to the first metal part, of the second metal part extending outward to form an extension edge, the extension edge being disposed around the second metal part, a second recessed portion being arranged at the first metal part, and the extension edge being connected to the second recessed portion in an embedded manner;
• and the top cover structure further comprising:
• a cover plate assembly;
• and
• a pressing block, a mounting hole being formed in the pressing block, the second metal part passing through the cover plate assembly and closely fitting the mounting hole, the first metal part and the pressing block are respectively abutted against two sides of the cover plate assembly;
• a welding groove being formed in a surface of the pressing block, the welding groove being in communication with a periphery of the mounting hole, the second metal part being fixed to the pressing block by welding, the welding groove being configured to accommodate a welding residue.

A battery cell, comprising a casing, a cell pack, and a top cover structure, the cell pack being disposed in the casing, the top cover structure being connected to an opening end of the casing in a sealed manner;

• the top cover structure comprising a terminal, the terminal comprising a first metal part and a second metal part connected to each other, a protruding portion being arranged at an end of one of the first metal part and the second metal part, a first recessed portion being arranged at an end of another one of the first metal part and the second metal part, the protruding portion being connected to the first recessed portion in an embedded manner;
• an edge of an end, close to the first metal part, of the second metal part extending outward to form an extension edge, the extension edge being disposed around the second metal part, a second recessed portion being arranged at the first metal part, and the extension edge being connected to the second recessed portion in an embedded manner;
• and the top cover structure further comprising:
• a cover plate assembly;
• and a pressing block, a mounting hole being formed in the pressing block, the second metal part passing through the cover plate assembly and closely fitting the mounting hole, the first metal part and the pressing block are respectively abutted against two sides of the cover plate assembly;
• a welding groove being formed in a surface of the pressing block, the welding groove being in communication with a periphery of the mounting hole, the second metal part being fixed to the pressing block by welding, the welding groove being configured to accommodate a welding residue.