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KR-102964272-B1 - BATTERY CELL AND BATTERY MODULE INCLUDING THE SAME

KR102964272B1KR 102964272 B1KR102964272 B1KR 102964272B1KR-102964272-B1

Abstract

A battery cell according to one embodiment of the present invention comprises: an electrode assembly including a plurality of electrode plates stacked with a separator interposed therebetween; and a battery case in which the electrode assembly is mounted in a housing portion, wherein the electrode assembly includes a plurality of electrode tabs formed by extending from each of the plurality of electrode plates, and the plurality of electrode tabs are arranged on the same line with respect to the same polarity to form an electrode tab array, and at least one protective member is bonded to the ends of the plurality of electrode tabs.

Inventors

  • 김상득
  • 오정식
  • 백가영
  • 김성

Assignees

  • 주식회사 엘지에너지솔루션

Dates

Publication Date
20260513
Application Date
20211026
Priority Date
20201123

Claims (17)

  1. An electrode assembly comprising a plurality of electrode plates stacked with a separator interposed therebetween; and The above electrode assembly includes a battery case mounted in a storage portion, and The electrode assembly comprises a plurality of electrode tabs formed by extending from each of the plurality of electrode plates, and The above plurality of electrode tabs are arranged on the same line with the same polarity to form an electrode tab array, and At least one protective member is bonded to the ends of the plurality of electrode tabs, and It further includes an electrode lead that is electrically connected to the electrode tab array and protrudes outwardly from the battery case. The above electrode lead includes a first electrode lead portion and a second electrode lead portion, and The first electrode lead portion extends along the end of the electrode tab array, and The second electrode lead portion protrudes outward from the first electrode lead portion in the direction of the battery case, and The above protective member is configured to separate the electrode tab of the electrode plate in which a short circuit has occurred from the first electrode lead portion, thereby forming a battery cell.
  2. In paragraph 1, One of the at least one protective member is bonded to some of the ends of the plurality of electrode tabs, and A battery cell in which another protective member among the at least one protective member is bonded to the remaining portion of the ends of the plurality of electrode tabs.
  3. In paragraph 1, A battery cell in which the protective member is bonded to each of the ends of the plurality of electrode tabs.
  4. In paragraph 1, The above protective member is a battery cell that breaks when heat above a first temperature is applied.
  5. In Paragraph 4, The above first temperature is the temperature of the resistance heat generated when a current greater than the first current flows through the electrode plate, in a battery cell.
  6. In paragraph 5, The above first current is a battery cell with a current of 10C or more.
  7. In paragraph 1, The above protective member is a battery cell comprising a Pb-Sn (lead-tin) alloy.
  8. In Paragraph 7, The above protective member is a battery cell made of an alloy comprising 30% to 45% by weight of lead (Pb) and 55% to 70% by weight of tin (Sn).
  9. delete
  10. In paragraph 1, A battery cell in which the end of the electrode tab array contacts the electrode lead.
  11. In Paragraph 10, A battery cell in which the end of the above-mentioned protective member contacts the above-mentioned electrode lead.
  12. In paragraph 1, The above battery case includes a sealing portion having a structure in which the outer periphery is sealed by heat fusion, and A battery cell comprising a lead film located in a portion corresponding to the sealing portion at least one of the upper and lower portions of the electrode lead.
  13. delete
  14. In Paragraph 12, The above lead film is a battery cell located in the second electrode lead portion.
  15. A pre-welding step of joining a protective member to an electrode tab formed extending from an electrode plate; An electrode assembly manufacturing step of manufacturing an electrode assembly by interposing a separator between a plurality of electrode plates joined with the above-mentioned protective member; A welding step in which the plurality of electrode tabs included in the electrode assembly are stacked together with the same polarity to form an electrode tab array, and the end of the electrode tab stack and the electrode lead come into contact with each other; and The method includes a packaging step of mounting the electrode assembly, which is electrically connected to the electrode lead, into a storage portion of a battery case. The above electrode lead includes a first electrode lead portion and a second electrode lead portion, and The first electrode lead portion extends along the end of the electrode tab array, and The second electrode lead portion protrudes outward from the first electrode lead portion in the direction of the battery case, and A method for manufacturing a battery cell in which the above protective member is configured to separate the electrode tab of the electrode plate in which a short circuit has occurred from the first electrode lead portion.
  16. delete
  17. A battery module including a battery cell according to claim 1.

Description

Battery cell and battery module including the same The present invention relates to a battery cell and a battery module including the same, and more specifically, to a battery cell with improved safety and a battery module including the same. With the increasing technological development and demand for mobile devices, the demand for secondary batteries as an energy source is rapidly increasing. In particular, secondary batteries are attracting significant interest as an energy source not only for mobile devices such as mobile phones, digital cameras, laptops, and wearable devices, but also for power devices such as electric bicycles, electric vehicles, and hybrid electric vehicles. These secondary batteries are classified according to the shape of the battery case into cylindrical and prismatic batteries, in which the electrode assembly is embedded in a cylindrical or prismatic metal can, and pouch-type batteries, in which the electrode assembly is embedded in a pouch-type case made of an aluminum laminate sheet. Here, the electrode assembly embedded in the battery case is a power generation element capable of charging and discharging, consisting of a positive electrode, a negative electrode, and a separator structure interposed between the positive and negative electrodes. It is classified into a jelly-roll type, which is wound with a separator interposed between long sheet-type positive and negative electrodes coated with active material, and a stack type, in which multiple positive and negative electrodes are sequentially stacked with a separator interposed between them. Among these, pouch-type batteries, in particular those with a structure in which a stacked or stacked/folded electrode assembly is embedded in a pouch-type battery case made of aluminum laminate sheets, are seeing a gradual increase in usage due to reasons such as low manufacturing costs, small weight, and easy deformation. FIG. 1 is an exploded perspective view of a conventional battery cell. FIG. 2 is an enlarged perspective view of the end of an electrode assembly included in the battery cell of FIG. 1. Referring to FIGS. 1 and 2, a conventional battery cell (10) comprises an electrode assembly (30) consisting of a positive electrode (33), a negative electrode (34), and a separator (35) interposed between them, and an electrolyte inside a battery case (20). Here, the secondary battery (10) is structured such that two electrode leads (40, 41) electrically connected to the positive electrode tabs (31) and negative electrode tabs (32) of the electrode assembly (30) are sealed so that they are exposed to the outside. Here, in order to test safety such as ignition or explosion during use, a pouch-type battery cell like a conventional battery cell (10) is tested by applying an external force to the fully charged battery or by penetrating it with a sharp metal foreign object to check for the occurrence of a short circuit and ignition. At this time, if a short circuit occurs in some electrodes within the battery cell (10), an overcurrent phenomenon occurs in which current moves from the electrodes where the short circuit did not occur to the electrodes where the short circuit occurred through the welded surfaces of the electrode tabs (31, 32). Accordingly, the electrodes where the short circuit occurred generate heat due to the overcurrent phenomenon, and subsequently reach a state of thermal runaway, resulting in a problem of ignition. In other words, it is necessary to develop a battery cell that can ensure safety by suppressing the overcurrent caused by other electrodes even if a short circuit occurs in some electrodes within the battery cell. Figure 1 is an exploded perspective view of a conventional battery cell. FIG. 2 is an enlarged perspective view of the end of the electrode assembly included in the battery cell of FIG. 1. FIG. 3 is an exploded perspective view of a battery cell according to the present embodiment. FIG. 4 is an enlarged perspective view of the end of the electrode assembly included in the battery cell of FIG. 2. FIG. 5 is an enlarged perspective view of the end of the electrode plate included in the electrode assembly of FIG. 3. FIG. 6 is an enlarged perspective view of the end of the electrode assembly when a short circuit occurs in a part of the electrode assembly of the battery cell of FIG. 2. FIG. 7 is a flowchart illustrating a method for manufacturing a battery cell according to the present embodiment. Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein. To clearly explain the present invention, parts unrelated to the explanation have been omitted, and the same reference numerals are used for identical or similar components throughout the specif