Abstract: The disclosure provides a battery pack. The battery pack includes a battery pack box body and a plurality of cells, wherein the battery pack box body has an accommodation space, the plurality of cells are stacked in the accommodation space, and each cell of the plurality of cells has a safety valve, a positive electrode terminal and a negative electrode terminal, the positive electrode terminal and the negative electrode terminal are located on a first surface of the cell, and the safety valve is located on a second surface of the cell; the battery pack box body further includes an accommodation pipeline and a cooling mechanism, wherein the accommodation pipeline and the cooling mechanism are both located in the accommodation space, the cooling mechanism is configured for supporting the second surface and cooling the cell, the accommodation pipeline is configured for accommodating molten substance collected by the accommodation holes.

Abstract: A cell and an assembly method thereof. The cell has an elongated structure with a positive electrode end and a negative electrode end. The negative electrode end is provided with a liquid injection hole, a tab protector and a single-cell collection board. A negative electrode column is connected to a negative tab on a cell core set through an aluminum plate, which is bendable to be accommodated into an accommodating cavity. The liquid injection hole is sunk into an avoidance hole on a top frame plate of the tab protector to clamp the tab protector. The electrolyte flows through the accommodating cavity to fill a core cavity, and the liquid injection hole is sealed by a sealing mechanism including a steel ball welded in thxoer liquid injection hole and a structural adhesive filled in the recess.