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JP-2026514533-A - Secondary battery and method for manufacturing the same

JP2026514533AJP 2026514533 AJP2026514533 AJP 2026514533AJP-2026514533-A

Abstract

Some embodiments of a secondary battery may include an electrode assembly with an electrode tab bundle on one side, electrode leads welded to the electrode tab bundle, and an adhesive layer located between the electrode tab bundle and the electrode leads and below the front edge of the electrode leads. Some embodiments of a secondary battery can prevent the electrode tab bundle from breaking and thus prevent a decrease in the performance of the secondary battery.

Inventors

  • ジュン・ホ・ピョ
  • キ・ウン・キム
  • イン・ジュン・キム
  • スン・チョル・キム
  • スン・ソク・ビン

Assignees

  • エルジー エナジー ソリューション リミテッド

Dates

Publication Date
20260511
Application Date
20250221
Priority Date
20240329

Claims (11)

  1. An electrode assembly including an electrode tab bundle on one side, Electrode leads welded to the electrode tab bundle, It is located between the electrode tab bundle and the electrode lead, A secondary battery comprising an adhesive layer located beneath the front edge of the electrode lead.
  2. The secondary battery according to claim 1, wherein the distance from the adhesive layer to the plurality of electrodes included in the electrode assembly is shorter than the distance from the welded portion to the plurality of electrodes included in the electrode assembly.
  3. The secondary battery according to claim 1, wherein the adhesive layer is separated from the welded portion.
  4. The secondary battery according to claim 1, wherein the adhesive layer is non-conductive.
  5. The secondary battery according to claim 1, wherein the adhesive layer has portions that do not overlap with the electrode leads in a direction parallel to the thickness direction of the electrode leads.
  6. The first step is to provide an electrode assembly including an electrode tab bundle on one side, The second step is to apply an adhesive layer to the electrode tab bundle, The third step includes welding the electrode tab bundle to the electrode lead, The aforementioned second step is performed before the aforementioned third step. A method for manufacturing a secondary battery, comprising applying the adhesive layer in the second step so that it is located below the front edge of the electrode lead to be welded in the third step.
  7. The method for manufacturing a secondary battery according to claim 6, wherein in the second step, the adhesive layer is applied such that the distance from the adhesive layer to the plurality of electrodes included in the electrode assembly is shorter than the distance from the welded portion formed by welding in the third step to the plurality of electrodes included in the electrode assembly.
  8. The method for manufacturing a secondary battery according to claim 6, wherein the welding is not performed on the adhesive layer in the third step.
  9. The method for manufacturing a secondary battery according to claim 6, wherein the adhesive layer in the second step is non-conductive.
  10. The method for manufacturing a secondary battery according to claim 6, wherein in the second step, the adhesive layer is applied such that there is a portion that does not overlap with the electrode lead to be welded in the third step, in a direction parallel to the thickness direction of the electrode lead.
  11. The method for manufacturing a secondary battery according to claim 6, wherein the welding in the third step is one or more of laser welding, resistance welding, and ultrasonic welding.

Description

This disclosure claims priority under Korean Patent Application No. 10-2024-0042963 dated March 29, 2024, and all contents of Korean Patent Application No. 10-2024-0042963 are incorporated by reference into this disclosure. This invention relates to a secondary battery and a method for manufacturing the same. In recent years, there has been growing interest in rechargeable batteries that can be used repeatedly for extended periods through recharging, as a way to reduce carbon emissions while decreasing reliance on fossil fuels. In particular, lithium-ion batteries, which use lithium ions as their energy source, offer superior energy density and lifespan, and research and development in this area is actively underway. As a result, lithium-ion batteries are used in a variety of fields, including portable electronic devices, vehicles, and ESS (Energy Storage Systems). Lithium-ion batteries are classified into cylindrical, prismatic, and pouch-type based on the shape of their battery case. Pouch-type lithium-ion batteries use film as the battery case, making assembly simpler than cylindrical and prismatic batteries which use a can-type case. They also offer superior heat dissipation, lifespan, and energy density. Furthermore, pouch-type lithium-ion batteries have a similar design for small and medium-to-large size batteries, giving them an advantage in market leadership. As a result, much development has been undertaken for pouch-type lithium-ion batteries. In a typical pouch-type lithium secondary battery, an electrode assembly consisting of multiple positive electrodes, multiple negative electrodes, and multiple separator films is located inside a film. On one side of the electrode assembly, there is an electrode tab bundle, to which multiple electrode tabs are welded. This electrode tab bundle is welded to the electrode leads and electrically connected to them. However, during the manufacturing process of the electrode leads, such as through mold notching, burrs are inevitably formed on one side. Traditionally, workers visually inspected both sides of the electrode leads to ensure that the burr-free side was in contact with the electrode tab bundle before inserting the lead. However, if a worker made a mistake, the burrs on the electrode leads would come into contact with the electrode tab bundle, as shown in Figure 1. Therefore, conventionally, there was a risk of the electrode tab bundle being torn due to worker error. If a secondary battery was manufactured with a torn electrode tab bundle, the performance of the secondary battery would inevitably deteriorate. This is a diagram to explain the conventional problem.This is a schematic side view illustrating some embodiments.This is a schematic top view illustrating some embodiments. The terms and words used herein should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather in a manner consistent with the technical idea of the present invention, based on the principle that inventors may appropriately define the meaning of terms and words in order to best describe their own invention. In this specification, terms such as “includes” and “have” are intended to specify the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, without prejudice to the presence or possibility of adding one or more other features, numbers, steps, actions, components, parts, or combinations thereof. Furthermore, when a part such as a layer, film, region, or plate is described as being “on top” of another part, this includes not only the case where it is “directly on top” of the other part, but also the case where another part lies in between. Conversely, when a part such as a layer, film, region, or plate is described as being “below” another part, this includes not only the case where it is “directly below” the other part, but also the case where another part lies in between. The embodiments and drawings are merely illustrative of the present invention and do not represent the entire technical concept of the invention; therefore, a variety of equivalents and modifications may be available to substitute them. Furthermore, in describing the present invention, if it is determined that a specific description of a known configuration or function may obscure the gist of the invention, such detailed description will be omitted. The drawings are provided to more fully explain the invention to an ordinary person of the art; therefore, the shapes, sizes, and numbers of components in the drawings may be exaggerated, omitted, or shown schematically for the sake of clarity. The shapes, sizes, proportions, and numbers of each component in the drawings do not fully reflect the actual shapes, sizes, proportions, and numbers of each component. The embodiments of the present invention will be described in detail below with reference to the drawings. One aspect of this invention relates to a sec