US-20260128486-A1 - ELECTRODE ASSEMBLY AND SECONDARY BATTERY INCLUDING THE SAME

US20260128486A1US 20260128486 A1US20260128486 A1US 20260128486A1US-20260128486-A1

Abstract

An electrode assembly and a secondary battery including the same are disclosed. An electrode assembly includes an electrode including a substrate, an electrode tab including a first tab portion joined to the substrate and a second tab portion extending from the first tab portion and arranged outward, and a protective tape attached to the substrate and the electrode tab to cover a portion of the first tab portion that includes an end portion of the first tab portion.

Inventors

Jin Hoon JANG
Han Sol MA
Su Han JUNG

Assignees

SAMSUNG SDI CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251106
Priority Date: 20241106

Claims (20)

1 . An electrode assembly comprising: an electrode comprising a substrate; an electrode tab comprising a first tab portion joined to the substrate and a second tab portion extending from the first tab portion and arranged outward; and a protective tape attached to the substrate and the electrode tab to cover a portion of the first tab portion that includes an end portion of the first tab portion.
2 . The electrode assembly as claimed in claim 1 , wherein, in an overlapping portion in which the protective tape and the electrode tab overlap, a first boundary line of the electrode tab corresponding to the end portion is not parallel to a second boundary line corresponding to a boundary of the protective tape.
3 . The electrode assembly as claimed in claim 2 , wherein, in the overlapping portion, the first boundary line is parallel to a longitudinal direction of the substrate; and the second boundary line is inclined at a certain angle with respect to the first boundary line.
4 . The electrode assembly as claimed in claim 3 , wherein the overlapping portion has an isosceles triangle-shaped boundary including the first boundary line and the second boundary line.
5 . The electrode assembly as claimed in claim 3 , wherein the overlapping portion has a right triangle-shaped boundary including the first boundary line and the second boundary line.
6 . The electrode assembly as claimed in claim 3 , wherein the overlapping portion has a trapezoid-shaped boundary, and the first boundary line and the second boundary line are non-parallel facing sides of the trapezoid shaped boundary.
7 . The electrode assembly as claimed in claim 1 , wherein the electrode includes a jelly-roll type electrode, and the second tab portion of the electrode tab is disposed to extend from the first tab portion toward a winding axis of the jelly-roll type electrode.
8 . An electrode assembly comprising: an electrode comprising a coated portion in which an active material layer is arranged on at least one surface of a substrate, and an uncoated portion on which the active material layer is not arranged; an electrode tab comprising a first tab portion joined to the uncoated portion, and a second tab portion extending from the first tab portion and arranged outward from the electrode in a width direction of the electrode; and a protective tape comprising a first tape portion to cover a portion of the first tab portion that includes an end portion of the first tab portion, and a second tape portion attached to the uncoated portion.
9 . The electrode assembly as claimed in claim 8 , wherein the end portion of the first tab portion has a first boundary line which is parallel to a longitudinal direction of the electrode, and a second boundary line of the protective tape overlapping the first tab portion is inclined at a certain angle with respect to the first boundary line.
10 . The electrode assembly as claimed in claim 9 , wherein the protective tape has a rhombus shape.
11 . The electrode assembly as claimed in claim 10 , wherein the first tape portion comprises a first vertex, which is one vertex of the rhombus shape, and the second tape portion comprises three remaining vertexes of the rhombus shape.
12 . The electrode assembly as claimed in claim 11 , wherein, in the second tape portion, a first sub-portion including a second vertex connected to the first vertex and a third sub-portion including a third vertex connected to the first vertex are folded toward the electrode.
13 . The electrode assembly as claimed in claim 12 , wherein the second tape portion has a same size as the electrode tab in the longitudinal direction of the electrode.
14 . The electrode assembly as claimed in claim 9 , wherein the protective tape has a parallelogram shape or a trapezoidal shape, and first facing sides of the parallelogram shape or second parallel sides of the trapezoidal shape are parallel to the width direction of the electrode.
15 . The electrode assembly as claimed in claim 14 , wherein a distance between the first facing sides or the second facing sides is greater than or equal to a width of the electrode tab.
16 . The electrode assembly as claimed in claim 9 , wherein the first boundary line meets the second boundary line at a vertex of the electrode tab.
17 . A secondary battery comprising: an electrode assembly; a case accommodating the electrode assembly; and a pair of terminals electrically connected to the electrode assembly and arranged on an outer surface of the case such that portions of the pair of terminals protrude from the case, wherein the electrode assembly comprises an electrode comprising a substrate, an electrode tab comprising a first tab portion joined to the substrate, and a second tab portion extending from the first tab portion and arranged outward, and a protective tape attached to the substrate and the electrode tab to cover a portion of the first tab portion that includes an end portion of the first tab portion.
18 . The secondary battery as claimed in claim 17 , wherein, in an overlapping portion in which the protective tape and the electrode tab overlap, a first boundary line of the electrode tab corresponding to the end portion is not parallel to a second boundary line corresponding to a boundary of the protective tape.
19 . The secondary battery as claimed in claim 18 , wherein, in the overlapping portion, the first boundary line is parallel to a longitudinal direction of the substrate, and the second boundary line is inclined at a certain angle with respect to the first boundary line.
20 . The secondary battery as claimed in claim 19 , wherein the overlapping portion has a right triangle-shaped boundary including the first boundary line and the second boundary line.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority to and the benefit of Korean Patent Application No. 10-2024-0155775, filed on Nov. 6, 2024 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. BACKGROUND 1. Field Aspects of embodiments of the present disclosure relate to an electrode assembly and a secondary battery including the same. 2. Description of the Related Art Secondary batteries are capable of being charged and discharged, unlike primary batteries that cannot be charged. Low-capacity secondary batteries may be used in small portable electronic devices, such as smartphones, feature phones, notebook computers, digital cameras, and camcorders, and high-capacity secondary batteries are widely used as power sources for driving motors and batteries for power storage of hybrid vehicles, electric vehicles, and the like. The secondary battery includes an electrode including a positive electrode and/or a negative electrode, an electrode assembly including the electrode, a case accommodating the electrode assembly, an electrode terminal connected to the electrode assembly, and the like. As technology advances, high-capacity secondary batteries are in demand. Accordingly, the capacity of the secondary battery may be increased, and a plurality of secondary batteries may be electrically connected and used. For example, the secondary battery may be applied to an electronic device in the form of a battery module including a plurality of secondary batteries and/or a battery pack including a plurality of battery modules. Depending on the implementation, a battery pack may include a plurality of secondary batteries. In this case, for example, the electronic device may be an electronic device requiring high output and/or high capacity, such as an electric vehicle. As the cell capacity of the secondary battery increases, an increase in cell expansion of the secondary battery occurs. The increase in cell expansion may cause various stability issues inside and outside the secondary battery. Particularly, cracks may occur or spread due to increased stress caused by a volume increase at or around a joint between different materials, which may cause an increase in leakage current, a disconnection, or a short circuit. Accordingly, a secondary battery with improved structural stability is desired even if a cell capacity increases. The above-described information disclosed in the background of the invention is provided to facilitate understanding of the background of the present invention, and may contain information that does not constitute the related art. SUMMARY According to an aspect of embodiments of the present invention, an electrode assembly, a secondary battery, and a battery pack capable of suppressing cracks from occurring at or around a joint portion of a substrate to which an electrode tab is joined are provided. However, aspects and technical objects to be achieved by the present invention are not limited to the above-described aspects and objects, and other aspects and objects which are not described above will be clearly understood by those skilled in the art through the following description of the present invention. According to one or more embodiments of the present invention, an electrode assembly includes an electrode including a substrate, an electrode tab including a first tab portion joined to the substrate and a second tab portion extending from the first tab portion and arranged outward, and a protective tape attached to the substrate and the electrode tab to cover a portion of the first tab portion that includes an end portion of the first tab portion. According to one or more embodiments of the present invention, an electrode assembly includes an electrode including a coated portion in which an active material layer is arranged on at least one surface of a substrate, and an uncoated portion on which the active material layer is not arranged, an electrode tab including a first tab portion joined to the uncoated portion, and a second tab portion extending from the first tab portion and arranged outward from the electrode in a width direction of the electrode, and a protective tape including a first tape portion to cover a portion of the first tab portion that includes an end portion of the first tab portion, and a second tape portion attached to the uncoated portion. According to one or more embodiments of the present invention, a secondary battery includes an electrode assembly, a case accommodating the electrode assembly, and a pair of terminals electrically connected to the electrode assembly and arranged on an outer surface of the case such that portions of the pair of terminals protrude from the case, wherein the electrode assembly includes an electrode including a substrate, an electrode tab including a first tab portion joined to the substrate and a second tab portion extending from the first tab portion