Battery cell and battery pack

Abstract

Provided in the present application are a battery cell and a battery pack, relating to the technical field of batteries. The battery cell comprises a wound core and a current collector plate. The current collector plate is welded to a tab layer of the wound core along a preset welding trajectory, wherein a first end of the preset welding trajectory is located between a root portion and an end portion of a first-turn tab, and a second end of the preset welding trajectory is located between a root portion and an end portion of an Nth-turn tab; one of the first end and the second end serves as a welding start point and the other serves as a welding end point; and the following conditions are satisfied: 0.95D1≤s≤0.99D1, and 1.01dN≤f≤1.05dN. In this way, the impact on the welding quality from the condition where inner and outer turns of a tab layer are low while a middle plane is high is reduced, thereby prolonging the cycle life of the battery cell and also reducing the risk of a short circuit in the battery cell.

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