A battery comprising: a box; a battery unit, provided in the box, the battery unit comprising a plurality of battery cells stacked in a first direction, each of the battery cells comprising two first walls provided oppositely in the first direction and two second walls provided in a second direction, an electrode terminal being provided on a second wall, and the first direction being orthogonal to the second direction; and an end plate, provided between a box inner wall of the box and the battery unit, the end plate having a first surface facing the box inner wall and a second surface facing a first wall, the first surface having a first region corresponding to a central region of the first wall and a second region corresponding to an edge region of the first wall, and the second surface being a flat surface that is attached to the first wall, wherein spacing (d) exists between the first region and the box inner wall, a buffering portion is provided in the spacing (d), the buffering portion is configured to be capable of abutting against the box inner wall to be deformed when the battery unit expands, thereby providing an expansion space for the expansion of the battery unit for buffering, and the second region abuts against the box inner wall, wherein at least a part of the buffering portion extends relative to the position of a bottom wall of the box in a direction obliquely upward towards the box inner wall, wherein an upward direction refers to a direction from the bottom wall of the box to an upper box wherein the first region is formed by providing a recess in the end plate, and wherein the buffering portion and the end plate are of an integral structure. a box; a battery unit, provided in the box, the battery unit comprising a plurality of battery cells stacked in a first direction, each of the battery cells comprising two first walls provided oppositely in the first direction and two second walls provided in a second direction, an electrode terminal being provided on a second wall, and the first direction being orthogonal to the second direction; and an end plate, provided between a box inner wall of the box and the battery unit, the end plate having a first surface facing the box inner wall and a second surface facing a first wall, the first surface having a first region corresponding to a central region of the first wall and a second region corresponding to an edge region of the first wall, and the second surface being a flat surface that is attached to the first wall, wherein spacing (d) exists between the first region and the box inner wall, a buffering portion is provided in the spacing (d), the buffering portion is configured to be capable of abutting against the box inner wall to be deformed when the battery unit expands, thereby providing an expansion space for the expansion of the battery unit for buffering, and the second region abuts against the box inner wall, wherein at least a part of the buffering portion extends relative to the position of a bottom wall of the box in a direction obliquely upward towards the box inner wall, wherein an upward direction refers to a direction from the bottom wall of the box to an upper box wherein the first region is formed by providing a recess in the end plate, and wherein the buffering portion and the end plate are of an integral structure.