Abstract: a first, a second, a third, and a fourth side plates of a battery casing are connected in sequence. The first and the third side plates are arranged opposite to each other, and the first side plate is shorter than the third side plate. The second and the fourth side plates are arranged opposite to each other, and the fourth side plate is shorter than the second side plate. A connecting plate adapted to mount a tab of a battery is provided between the first and the fourth side plates and connected to the first and the fourth side plates, and the connecting plate is shorter than the second and the third side plates. The first, the second, the third, and the fourth side plates and the connecting plate are located at the same side of a support plate, and work with the support plate to define an accommodating cavity.

Abstract: A battery housing includes an upper housing and a lower housing. The lower housing includes a bottom portion and first side walls, the first side walls extend upward from edges of the bottom portion, the bottom portion and the first side walls enclose a cavity, and at least one of the first side walls having a first flange on an end of the first side wall away from the bottom portion. The upper housing is located above the lower housing, the upper housing includes a top portion and a second flange, a second concave structure is disposed at a joint between the second flange and the top portion, the first flange is in contact with the second flange by welding to obtain melt, and the melt is disposed in the second concave structure.

Abstract: A battery housing includes a first housing and a second housing. An accommodating space with an opening is defined by a bottom plate, two first side plates and two second side plates of the first housing. The second housing includes a body, and two first extending plates and two second extending plates arranged on a peripheral edge of the body. An avoiding region is formed on one second side plate. In a first direction, a width of the second extending plate corresponding to the second side plate provided with the avoiding region is smaller than or equal to a width of the avoiding region, and additionally, a width of the two first extending plates is greater than a width of the second extending plate. The second housing covers the opening of the first housing, and the two first extending plates and the two first side plates are fixedly connected.