The embodiments of the present disclosure provide a secondary battery, a battery module, a battery pack, a device, and a manufacturing method. The secondary battery includes: an electrode unit, including a main body portion and a first tab and a second tab extending out from the main body portion; a casing, including an accommodating cavity for accommodating the main body portion and a first opening which is in communication with the accommodating cavity; a first cover plate capping the first opening, the first cover plate including a first relief hole penetrating therethrough, the first tab passes through the first relief hole and is connected to a side of the first cover plate facing away from the accommodating cavity; and a sealing plate, which is sealingly connected to the side of the first cover plate facing away from the accommodating cavity and covers the first relief hole.

A battery includes a power generating element including a positive electrode layer, a negative electrode layer, and an electrolyte layer, an inner terminal electrode electrically connected to the power generating element, and a laminate film accommodating the power generating element and the inner terminal electrode. The laminate film includes a metal layer, an inner resin layer located closer to the power generating element than the metal layer, and an outer resin layer on an opposite side of the metal layer from the inner resin layer. The inner resin layer has an inner opening through which the metal layer is exposed. The inner terminal electrode is electrically connected to the metal layer through the inner opening. The inner terminal electrode and the metal layer each have an uneven surface over a contact area between the inner terminal electrode and the metal layer. The uneven surfaces engage with each other.

A battery cell assembly, including a rolled cell formed from a first electrode and a second electrode rolled together about a longitudinal axis. The rolled cell includes a primary section in which the first electrode and the second electrode overlap in a radial direction from the longitudinal axis, and a first extension end extending from a first longitudinal end of the primary section and formed from a first edge section of the first electrode. The first edge section includes a first folded portion folded to contact an adjacent portion of the first edge section. The battery cell assembly further includes a first end cap coupled to the rolled cell and contacting the first folded portion.

A pouch cell includes a copper foil forming a pouch, an active material layer adjacent to the copper foil inside the pouch forming a cathode with the copper, and a lithium-based anode inside the pouch. The cell includes a separator interposing the one active material layer and the lithium-based anode, and an electrolyte. In other embodiments, the active material forms an anode with the copper and the cathode is a lithium-based cathode.

A pouch cell includes a copper foil forming a pouch, an active material layer adjacent to the copper foil inside the pouch forming a cathode with the copper, and a lithium-based anode inside the pouch. The cell includes a separator interposing the one active material layer and the lithium-based anode, and an electrolyte.

One variation of a battery unit includes: a series of anode collectors; a set of anode electrodes including anode material arranged on both side of the anode collectors; a set of anode interconnects interposed between and electrically coupling adjacent anode collectors and folded to locate the anode collectors in a boustrophedonic anode stack; a series of cathode collectors; a set of cathode electrodes including cathode material arranged on both side of the cathode collectors; a set of cathode interconnects interposed between and electrically coupling adjacent cathode collectors and folded to locate the cathode collectors in a boustrophedonic cathode stack with cathode collectors interdigitated between anode collectors in the boustrophedonic anode stack; and a set of separators arranged between the anode and cathode electrodes and transporting solvated ions between the anode and cathode electrodes.

Provided are a manufacturing method of a core assembly for battery, a core assembly for battery, and a battery pack including the core assembly. The method includes; providing a jelly-roll including a cylindrical main body and a tab group including tabs stacked in an axial direction of the main body and electrically connected to an axial end of the main body, each tab extending outward in a radial direction of the main body; providing a current collecting member including a current collecting portion; electrically connecting the current collecting portion to at least one of the tabs so that the current collecting portion extends outward in the radial direction; and bending the current collecting portion and at least one part of the tabs inward in the radial direction so that no current collecting portion or tab extends beyond an outer peripheral surface of the main body in the radial direction.

The present disclosure provides a cap assembly for a secondary battery, a secondary battery and a battery module. The cap assembly for the secondary battery includes a cap plate, a first electrode terminal, and a sealing member, wherein: the cap plate has an electrode lead-out hole; the first electrode terminal includes a first terminal board and a second terminal board connected with the first terminal board, wherein the first terminal board is located at a side of the second terminal board away from the cap plate, the second terminal board covers the electrode lead-out hole, and the material of the first terminal board and the material of the second terminal board have different base metals; the sealing member surrounds the electrode lead-out hole and is disposed between the cap plate and the first electrode terminal to seal the electrode lead-out hole.

The present disclosure provides a cap assembly for a secondary battery, a secondary battery and a battery module. The cap assembly for the secondary battery includes a cap plate, a first electrode terminal, and a sealing member, wherein: the cap plate has an electrode lead-out hole; the first electrode terminal includes a first terminal board and a second terminal board connected with the first terminal board, wherein the first terminal board is located at a side of the second terminal board away from the cap plate, the second terminal board covers the electrode lead-out hole, and the material of the first terminal board and the material of the second terminal board have different base metals; the sealing member surrounds the electrode lead-out hole and is disposed between the cap plate and the first electrode terminal to seal the electrode lead-out hole.

A position assurance apparatus, which is used for a connector assembly connected to a signal circuit are provided. The connector assembly comprises a first connector and a second connector, which are connected in pairs, wherein the first connector is connected to the signal circuit, and the second connector is inserted in the first connector. The position assurance apparatus comprises a first connecting portion and a second connecting portion, which are electrically connected to each other. The first connecting portion and the second connecting portion are configured to be electrically connected to the signal circuit by means of the first connector, so as to turn on the signal circuit when the first connector and the second connector are inserted in place.