Abstract: The present application relates to a secondary battery, a battery module and an apparatus. The secondary battery includes an electrode assembly and a casing. The electrode assembly includes a main body portion and a tab portion, the tab portion extending out from the main body portion along an end of the main body portion and including an outer peripheral surface. The casing includes an accommodating hole for accommodating the electrode assembly. The casing includes a limiting protrusion. The outer peripheral surface extends around an axis of the accommodating hole. The limiting protrusion protrudes toward the tab portion and presses against the outer peripheral surface of the tab portion. The limiting protrusion is adapted to limit a position of the tab portion. The secondary battery provided by the present application can reduce the possibility of fatigue fracture of the adapting piece.

Abstract: The present application relates to a secondary battery, a battery module and an apparatus. The secondary battery includes an electrode assembly and a casing. The electrode assembly includes a main body portion and a tab portion, the tab portion extending out from the main body portion along an end of the main body portion and including an outer peripheral surface. The casing includes an accommodating hole for accommodating the electrode assembly. The casing includes a limiting protrusion. The outer peripheral surface extends around an axis of the accommodating hole. The limiting protrusion protrudes toward the tab portion and presses against the outer peripheral surface of the tab portion. The limiting protrusion is adapted to limit a position of the tab portion. The secondary battery provided by the present application can reduce the possibility of fatigue fracture of the adapting piece.

Abstract: A welding method includes placing a housing covered with an end cap into a jig, where a clearance structure is created on the jig and available for exposing a target weld zone between the end cap and the housing, and the target weld zone includes a first target weld zone section and a second target weld zone section located on two opposite sides of the end cap respectively; and moving the jig to a first welding station of a welding device; welding, by a first welding head of the welding device, the first target weld zone section through the clearance structure; and welding, by a second welding head of the welding device, the second target weld zone section through the clearance structure. The first welding station is located between the first welding head and the second welding head.

Abstract: The present application relates to a secondary battery, a battery module and an apparatus. The secondary battery includes an electrode assembly and a casing. The electrode assembly includes a main body portion and a tab portion, the tab portion extending out from the main body portion along an end of the main body portion and including an outer peripheral surface. The casing includes an accommodating hole for accommodating the electrode assembly. The casing includes a limiting protrusion. The outer peripheral surface extends around an axis of the accommodating hole. The limiting protrusion protrudes toward the tab portion and presses against the outer peripheral surface of the tab portion. The limiting protrusion is adapted to limit a position of the tab portion. The secondary battery provided by the present application can reduce the possibility of fatigue fracture of the adapting piece.