An electrode assembly having a first electrode, a second electrode, and a separator therebetween, the first electrode, the second electrode, and the separator being wound in a jelly-roll shape is provided. The first electrode includes a first winding start portion, a first winding end portion, and a first coating portion having a first active material provided between the first winding start portion and the first winding end portion. The second electrode includes a second winding start portion, a second winding end portion, and a second coating portion having a second active material provided between the second winding start portion and the second winding end portion. A first electrode tab is provided at the first winding end portion of the first electrode. A first protective member is attached to a surface of the second winding end portion of the second electrode facing the first electrode tab.

A secondary battery includes an electrode assembly disposed within a constraint. The electrode assembly comprises a population of unit cells comprising an electrode current collector layer, an electrode layer, a separator layer, a counter-electrode layer, and a counter-electrode current collector layer in stacked succession. A subset of the unit cell population includes extended spacer members between the electrode current collector layer and the counter-electrode current collector layer. One of the spacer members is spaced in a transverse direction from the other extended spacer member, at least a portion of the counter-electrode active material of the counter-electrode layer being located between the spacer members such that the portion of the counter-electrode active material and the spacer members lie in a common plane defined by x and z axes, wherein each of the extended spacer members extend a distance SD in the x-axis direction beyond an x-axis edge of the constraint.

An electrode plate which is to be contained in a wound or multilayer electrode body, and which is provided with: a band-like electrode plate core body; mixture layers that are formed on both surfaces of the electrode plate core body; and a tab that extends from one end of the electrode plate core body in the short-side direction. With respect to this electrode plate, the front edge of the electrode plate core body at the end from which the tab extends is covered by the mixture layers.

An electrode plate which is to be contained in a wound or multilayer electrode body, and which is provided with: a band-like electrode plate core body; mixture layers that are formed on both surfaces of the electrode plate core body; and a tab that extends from one end of the electrode plate core body in the short-side direction. With respect to this electrode plate, the front edge of the electrode plate core body at the end from which the tab extends is covered by the mixture layers.

Disclosed herein is a method for manufacturing an electrode assembly. The method may include a step of applying an electrode active material to at least a portion of an electrode collector, which is formed by sequentially stacking a first electrode foil, an electrode insulating layer, and a second electrode foil, to manufacture an electrode, a step of stacking the electrode and a separator, and a step of connecting an electrode lead to a non-coating portion that is not coated with the electrode active material on the electrode collector. The step of connecting the electrode lead may include passing a coupling part through the electrode collector and the electrode lead to connect the electrode collector to the electrode lead.

Disclosed herein is a method for manufacturing an electrode assembly. The method may include a step of applying an electrode active material to at least a portion of an electrode collector, which is formed by sequentially stacking a first electrode foil, an electrode insulating layer, and a second electrode foil, to manufacture an electrode, a step of stacking the electrode and a separator, and a step of connecting an electrode lead to a non-coating portion that is not coated with the electrode active material on the electrode collector. The step of connecting the electrode lead may include passing a coupling part through the electrode collector and the electrode lead to connect the electrode collector to the electrode lead.

A secondary includes an electrode assembly having a jelly roll structure including a positive electrode sheet, a negative electrode sheet, and a separator; a cylindrical case in which the electrode assembly is received; and a flat spiral spring positioned between an outer peripheral surface of the electrode assembly and an inner surface of the cylindrical case.

A secondary includes an electrode assembly having a jelly roll structure including a positive electrode sheet, a negative electrode sheet, and a separator; a cylindrical case in which the electrode assembly is received; and a flat spiral spring positioned between an outer peripheral surface of the electrode assembly and an inner surface of the cylindrical case.

A battery cell includes an electrode assembly and a housing. A thickness of the electrode assembly is T1 mm. The housing includes a first surface; a second surface at a distance T2 mm from the first surface; a first lateral edge with arc shape and connected to the second surface and possessing a radius of R mm; a third surface connected to the first lateral edge; and a second lateral edge including a first part extending away from the electrode assembly by starting from a first edge of the first surface and a second edge of the third surface, and a second part extending toward the electrode assembly and possessing an ending edge connected to the third surface. Along the thickness direction, a distance between the second edge of the third surface and the ending edge is Z mm, and (T2−Z)/2≤R≤T1/2+0.3.

A battery cell includes an electrode assembly and a housing. A thickness of the electrode assembly is T1 mm. The housing includes a first surface; a second surface at a distance T2 mm from the first surface; a first lateral edge with arc shape and connected to the second surface and possessing a radius of R mm; a third surface connected to the first lateral edge; and a second lateral edge including a first part extending away from the electrode assembly by starting from a first edge of the first surface and a second edge of the third surface, and a second part extending toward the electrode assembly and possessing an ending edge connected to the third surface. Along the thickness direction, a distance between the second edge of the third surface and the ending edge is Z mm, and (T2−Z)/2≤R≤T1/2+0.3.