Battery, battery pack and power-consuming device

Abstract

A battery characterized in that it comprises a housing, a cover plate, and a battery cell, wherein a receiving space is provided inside the housing, the housing has an opening area at one end in a first direction perpendicular to the cover plate, the battery cell can be inserted into the receiving space through the opening area, the cover plate is welded to the opening area and closes the receiving space, the housing is cuboid in shape and comprises a short side wall perpendicular to a second direction and a long side wall perpendicular to a third direction, wherein the first direction, the second direction, and the third direction are perpendicular to each other in pairs, the short side wall has a short wall edge at its end located near the cover plate in the first direction, and the long side wall has a long wall edge at its end located near the cover plate in the first direction.the long wall edge is longer than the short wall edge, the short wall edge and the long wall edge form at least part of the opening area, a first projection is provided on the inner surface of the short side wall towards the battery cell, the first projection is arranged near the short wall edge, the cover plate is rectangular and comprises a short side perpendicular to the second direction and a long side perpendicular to the third direction, the long side is longer than the short side, the long side is welded to the long wall edge, the short side is welded to the short wall edge, the battery cell comprises a cell body and a cell outlet section, the cell outlet section comprises a positive terminal tab and a negative terminal tab, the positive terminal tab and the negative terminal tab each extend from two cell side surfaces of the cell body opposite each other in the second direction,the two cell side faces are perpendicular to the cover plate, the connecting tab of the positive connecting tab and the negative connecting tab that is closer to the short side wall projects from the corresponding cell side face towards the short side wall, the cover plate is made of steel, the dimension of the first projection in the second direction is a1, the dimension of the short side wall in the second direction is a2, the length of the short side is b1, the length of the long side is b2, a melting zone and a heat-affected zone surrounding the melting zone are formed at the weld point between the short wall edge and the short side, the hardness c of the heat-affected zone is 10×10−4 HV−1≤b1b2 / (c×a1a2)≤4500×10−4 HV−1, where the units of a1, a2, b1 and b2 are each mm and the unit of c is HV.