BATTERY CELL AND MANUFACTURING METHOD THEREFOR, BATTERY, AND ELECTRIC DEVICE

A battery cell and a manufacturing method therefor, a battery, and an electric device. The battery cell comprises: a housing (1), an opening (11) being formed in an end portion of the housing (1); an electrode assembly provided in the housing (1) and comprising an electrode body (21) and a first tab (22), the first tab (22) being led out from one end of the electrode body (21); an end cap (3) closing the opening (11), the outer periphery of the end cap (3) and the housing (1) being fixed by welding; and a conductive member (4) located between the electrode assembly and the end cap (3), the conductive member (4) being electrically connected to the first tab (22), the conductive member (4) being electrically connected to at least one of the end cap (3) and the housing (1), and the outer edge of the conductive member (4) extending to a position close to a welding region. Residual heat generated by the welding of the end cap and the housing is used for indirectly melting and welding the conductive member, welding energy is reduced, the generation of micro-cracks can be reduced, electrolyte leakage is prevented, and the performance and safety of the battery cell are improved.