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KR-20260064351-A - SEPARATOR, ELECTRODE STACK INCLUDING THE SEPARATOE, AND SECONDARY BATTERY INCLUDING THE ELECTRODE STACK

KR20260064351AKR 20260064351 AKR20260064351 AKR 20260064351AKR-20260064351-A

Abstract

A secondary battery according to the present invention comprises a first electrode, a second electrode stacked alternately with the first electrode along a stacking direction, and a separator arranged to separate the first electrode and the second electrode from each other. The separator comprises a first separator portion located between the first electrode and the second electrode, a second separator portion located on the opposite side of the first separator portion with respect to the first electrode, and a connecting portion connecting the first separator portion and the second separator portion and covering the end of the first electrode. The connecting portion has a gas discharge hole formed therein, the length in the longitudinal direction parallel to the extension direction of the end of the first electrode being longer than the width and having rounded corners.

Inventors

  • 김도현
  • 정민지
  • 박종필

Assignees

  • 주식회사 엘지에너지솔루션

Dates

Publication Date
20260507
Application Date
20241031

Claims (20)

  1. First electrode; A second electrode stacked alternately with the first electrode along the stacking direction; and It includes a separator arranged to separate the first electrode and the second electrode from each other, The above separator is, A first separator portion located between the first electrode and the second electrode; A second separator portion located on the opposite side of the first separator portion with respect to the first electrode; and It includes a connecting portion that connects the first separator portion and the second separator portion and covers the end of the first electrode, The above-mentioned connecting portion is a secondary battery in which a gas discharge hole is formed with a length in the longitudinal direction parallel to the extension direction of the first electrode end that is longer than the width and has rounded corners.
  2. In paragraph 1, A secondary battery in which the longitudinal end of the above gas discharge hole is drawn inward as it extends outward in the width direction.
  3. In paragraph 1, A secondary battery having a plurality of gas discharge holes arranged along the extension direction of the first electrode end.
  4. In paragraph 3, The above connecting portion is a secondary battery comprising a bridge portion connecting the first separator portion and the second separator portion between a plurality of the above gas discharge holes.
  5. In paragraph 4, A secondary battery in which the length of the gas discharge hole in the first electrode extension direction is longer than the length of the bridge portion in the first electrode extension direction.
  6. In paragraph 4, A secondary battery in which the length of the bridge portion in the first electrode extension direction is 1/10 or less of the length of the connecting portion in the first electrode extension direction.
  7. In paragraph 4, The above bridge portion is a secondary battery in which the width of the portion connected to the first separator portion or the second separator portion is greater than the width located between the first separator portion and the second separator portion.
  8. In paragraph 4, A secondary battery comprising a space-forming portion that is opposite and spaced apart so as to form a gas movement space between the bridge portion and the first electrode.
  9. In paragraph 4, It further includes an end bridge portion located on the outer side with respect to the arrangement direction of a plurality of the above gas discharge holes, and A secondary battery in which the width of the end bridge portion is wider than the width of the bridge portion.
  10. In paragraph 1, The above gas discharge hole is a secondary battery that is bent toward the first separator portion or the second separator portion at the end of the first electrode.
  11. In paragraph 1, The above gas discharge hole is a secondary battery having a width greater than the thickness of the first electrode end.
  12. In paragraph 1, The above gas exhaust hole is a secondary battery that overlaps with the first electrode and the stacking direction so that the first electrode is exposed with respect to the stacking direction.
  13. In paragraph 1, A secondary battery in which the above gas exhaust hole is configured to limit overlap with the second electrode in order to prevent the first electrode and the second electrode from coming into contact.
  14. In paragraph 1, It includes a receiving portion for accommodating the first electrode, the second electrode, and the separator, and a side portion configured to extend from one side of the receiving portion and be sealed. A secondary battery in which the above gas discharge hole is configured to face the above side portion.
  15. In paragraph 1, The above connection part is defined as a first connection part, and The first connecting portion is connected to one end of the first separator portion and one end of the second separator portion adjacent to the one end of the first separator portion, and The above separator is, A third separator portion located on the opposite side of the first separator portion with respect to the second electrode; and A secondary battery further comprising a second connecting portion connected to the other end of the second separator portion and the first end of the third separator portion adjacent to the other end of the second separator portion.
  16. First electrode; A second electrode stacked alternately with the first electrode along the stacking direction; and A first separator portion located between the first electrode and the second electrode; A second separator portion located on the opposite side of the first separator portion with respect to the first electrode; and It includes a connecting portion that connects the first separator portion and the second separator portion and covers the end of the first electrode, The above connecting portion is an electrode stack having a gas discharge hole formed therein that allows gas to move and overlaps with respect to either the first electrode or the second electrode in the stacking direction, while preventing overlap with respect to the other.
  17. In Paragraph 16, The above gas exhaust hole is an electrode laminate in which the length in the longitudinal direction parallel to the extension direction of the first electrode end is longer than the width and the corners are rounded.
  18. In Paragraph 16, The longitudinal end of the above gas discharge hole is an electrode laminate that is drawn inward as it extends outward in the width direction.
  19. In Paragraph 16, The above gas exhaust holes are provided in plurality, and the electrode stack is arranged along the extension direction of the first electrode end.
  20. A first separator portion configured to face the first surface of the first electrode; A second separator portion configured to face a second surface opposite to the first surface of the first electrode; and It includes a connecting portion configured to connect the first separator portion and the second separator portion, The above connecting portion includes gas discharge holes provided in plurality, the length in the longitudinal direction being longer than the width, a bridge portion formed between the plurality of gas discharge holes, and an end bridge portion formed on the outer side of the plurality of gas discharge holes. The length of the gas discharge hole is longer than the length of the bridge part, and A separator in which the length of the end bridge portion is longer than the length of the bridge portion.

Description

Separator, electrode stack including the separator, and secondary battery including the electrode stack The present invention relates to a separator, an electrode stack including the separator, and a secondary battery including the electrode stack. More specifically, the invention relates to a separator configured to facilitate gas discharge, an electrode stack including the separator, and a secondary battery including the electrode stack. Generally, a secondary battery configured to produce electricity includes an electrode stack comprising a plurality of electrodes and a separator positioned between each electrode, and a battery case housing the electrode stack. Among the processes involved in manufacturing secondary batteries is the degassing process. The degassing process is performed after the activation process, in which the electrode stack is initially housed in a battery case and the battery is activated by performing preliminary charging and discharging. More specifically, gas is generated as the electrolyte reacts with the electrodes during the activation process, and the degassing process is designed to remove this gas. If the gas is not removed from the secondary battery, it hinders the movement of ions, such as lithium ions, between the electrodes, leading to a decrease in electricity generation. When a separator is formed by being composed of multiple individual sheets separated from one another, it may be easy for gas to move between adjacent separators. However, if adjacent separators are connected to each other, or if a single separator separates each of the multiple electrodes, a problem may arise where it is difficult for gas to move to a part of the separator. In other words, a problem may arise where gas is trapped between the separator and the electrode. The aforementioned background technology is one that the inventor possessed or acquired in the process of deriving the contents of the disclosure of the present application, and it cannot be considered as prior art disclosed to the general public prior to the filing of this application. FIG. 1 is an assembly diagram of a secondary battery according to a first embodiment of the present invention. Figure 2 is a cross-sectional view showing the battery cases illustrated in Figure 1 cut while in contact with each other. FIG. 3 is a side view showing the electrode assembly illustrated in FIG. 2 as viewed from the side. FIG. 4 is a cross-sectional view showing the first electrode, second electrode, and separator shown in FIG. 3 cut. FIG. 5 is a perspective view illustrating the first electrode, the second electrode, and the separator shown in FIG. 4. FIG. 6 is a front view of the first electrode, second electrode, and separator shown in FIG. 5, viewed from above. Figure 7 is a perspective view illustrating the separation membrane shown in Figure 6. Figure 8 is an enlarged view showing the portion where the gas discharge hole shown in Figure 6 is located. FIG. 9 is an enlarged view illustrating a separation membrane according to a second embodiment of the present invention. FIG. 10 is an enlarged view illustrating a separation membrane according to a third embodiment of the present invention. FIG. 11 is an enlarged view illustrating a separation membrane according to a fourth embodiment of the present invention. Hereinafter, preferred embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in various different forms and is not limited or restricted by the following embodiments. In order to clearly explain the present invention, detailed descriptions of related prior art that are irrelevant to the explanation or that may unnecessarily obscure the essence of the invention have been omitted. Furthermore, when assigning reference numerals to the components of each drawing in this specification, identical or similar reference numerals are assigned to identical or similar components throughout the entire specification. Furthermore, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. The various embodiments of this document and the terms used therein are not intended to limit the technical features described in this document to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of said embodiments. In relation to the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of the noun corresponding to the item may include one or multiple items, unless