An electrode assembly, a battery cell, a battery, and a method and device for manufacturing an electrode assembly are provided. In some embodiments, the electrode assembly includes a positive electrode plate and a negative electrode plate. The positive electrode plate and the negative electrode plate are wound or folded to form a bend region. The positive electrode plate includes a plurality of bend portions located in the bend region. Each bend portion includes a positive current collecting layer and a positive active material layer. The positive current collecting layer is coated with the positive active material layer on at least one surface in a thickness direction of the positive electrode plate. A barrier layer is disposed between the positive current collecting layer and the positive active material layer.

A method includes, by a folding station: receiving an anode assembly including anode collectors connected by anode interconnects and coated with a separator; receiving a cathode assembly including cathode collectors connected by cathode interconnects; locating a first anode collector over a folding stage; locating a first cathode collector over the first anode collector to form a first battery cell between the first anode collector and the first cathode collector; folding a first anode interconnect to locate a second anode collector over the first cathode collector to form a second battery cell between the first cathode collector and the second anode collector; folding a first cathode interconnect to locate a second cathode collector over the second anode collector to form a third battery cell between the second anode collector and the second cathode collector; wetting the separator with solvated ions; and loading the anode and cathode assemblies into a battery housing.

An electrode assembly includes a plurality of electrodes arranged in a stack along a stacking axis, where each of the electrodes in the stack is separated along the stacking axis from a successive one of the electrodes in the stack by a respective separator portion positioned therebetween. At least one outer surface of the stack may include a pattern defining a first region and a second region, where a second portion of the stack corresponding to the second region has a different property or height from a first portion of the stack corresponding to the first region. The property may include any one of shading or color of the at least one outer surface of the stack, air permeability of the separator portions in the first and second regions, and adhesive force between the electrodes and separator portions in the first and second regions.

A producing method of a flat-wound electrode body, which is formed by winding a strip-shaped positive electrode plate and a strip-shaped negative electrode plate via a pair of separators into a flat shape, includes winding of forming a cylindrical-wound electrode body by winding the positive electrode plate and the negative electrode plate interposed with the pair of separators into a cylindrical shape, and pressing of forming the flat-wound electrode body by pressing and flattening the cylindrical-wound electrode body. The pressing is to perform pressing to position a positive electrode end portion at a winding end of the positive electrode plate in a flat portion of the flat-wound electrode body.

An auxiliary electrode includes a conductive layer having a first major surface in an X-Y plane, the conductive layer is electrically conductive and has a first surface area. The auxiliary electrode includes a first carrier ion supply layer and a second carrier ion supply layer, each carrier ion supply layer comprising a material that supplies carrier ions for an electrode of the secondary battery. The first carrier ion supply layer covers a first region of the first major surface of the conductive layer and the second carrier ion supply layer covers a second region of the first major surface of the conductive layer. The first and second regions are separated by a third region, the third region configured to be folded such that the first region and the second region are substantially parallel, and the third region is substantially perpendicular to the first and second regions in the folded configuration.

An electrode assembly includes a first electrode plate. The first electrode plate includes a first current collector, a first active material layer and a first insulation layer. The first current collector includes a first surface and a second surface. The first surface and the second surface are provided opposite to each other. The first active material layer is provided on the first surface. The first insulation layer is located between the first current collector and the first active material layer.

An electrode assembly includes first and second electrode plate having opposite polarities, and a separator separating the first and second electrode plates. The first electrode plate includes two first stack sections and a bend section connecting the first stack sections and including a guide portion configured to guide the bend section to bend during production. The second electrode plate includes a second stack section disposed between the first stack sections. The separator includes two separation sections each disposed between the second stack section and one first stack section. Thickness Da of each first stack section, thickness Dc of the second stack section, and thickness Ds of each separation section in a stacking direction of the first stack sections, and a dimension w of the guide portion in a bending direction of the bend section satisfy: Dc+2Ds≤w≤2×(Dc+2Ds+Da).

A secondary battery includes an electrode assembly including a first electrode bent in a zigzag shape, a second electrode bent in a zigzag shape to overlap the first electrode, and a separator bent in a zigzag shape to be interposed between the first and second electrodes; a can configured to accommodate the electrode assembly; and a cap part mounted in an opening of the can. An upper end of the first electrode is disposed on the uppermost end of the electrode assembly to extend longer than the second electrode, a lower end of the second electrode on the lowermost end of the electrode assembly extends longer than the first electrode, a first protrusion piece bonded to the cap part provided on the upper end of the first electrode, and a second protrusion piece bonded to the can provided on the lower end of the second electrode.

Disclosed in the present invention is a secondary battery having a safety vent integrally formed with a side wall part of a case thereof whereby the secondary battery is improved in safety and has the effect of reducing manufacturing cost and simplifying process. As an example, disclosed is a secondary battery comprising: an electrode assembly; a case for receiving the electrode assembly; and a cap plate for covering an opened opening of the case, wherein the case includes two pairs of side wall parts, the side wall parts in each pair facing each other, and a bottom part perpendicular to the side wall parts, and a safety vent is integrally formed with an edge part of one region selected from the side wall parts and the bottom part.

An X-ray inspection apparatus for a cylindrical secondary battery according to the present invention comprises: an inspection chamber; a transfer unit for transferring a cylindrical secondary battery into the inspection chamber; an inspection body moving while holding the secondary battery; an X-ray source; an X-ray detector; a discharge unit for discharging the inspected secondary battery outside the inspection chamber;

and an alignment mechanism arranged along a moving path of the inspection body so as to align the cylindrical secondary battery. Further, in the X-ray inspection apparatus for a cylindrical secondary battery according to the present invention, the alignment mechanism comprises: one or more sensing unit for sensing the position of a specific portion of the cylindrical secondary battery; and one or more contact unit operable between a standby position in which the contact unit do not come into contact with the secondary battery and a contact position in which the contact unit can come into contact with the secondary battery.