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CN-224217505-U - Battery cell and battery pack

CN224217505UCN 224217505 UCN224217505 UCN 224217505UCN-224217505-U

Abstract

The application discloses a battery cell and a battery pack, wherein the battery cell comprises a plurality of pole pieces, first pole lugs, second pole lugs and isolating films, the pole pieces are arranged in a stacked mode along a first direction, the isolating films are arranged between two adjacent pole pieces, two pole pieces located at the outermost side along the first direction are end pole pieces, the first pole lugs are electrically connected with one end pole piece, and the second pole lugs are electrically connected with the other end pole piece. Therefore, the complex procedure of independently welding the pole lugs on each pole piece in the traditional scheme is omitted, the assembly steps of the pole lugs are greatly reduced, the production flow is simplified, the process control difficulty caused by the alignment deviation of the pole lugs is reduced, and the production efficiency and the product consistency are improved. In addition, the number of the pole lugs is reduced, the superposition effect of contact resistance when the traditional multipolar lugs are connected in parallel can be avoided, the current transmission paths are more centralized and unified, the high-current charge and discharge performance is improved, and the problem of limited overcurrent capacity caused by overhigh resistance in the traditional scheme is solved.

Inventors

  • HUANG ZIHAN
  • ZHAO JIAXING
  • LI WEI
  • LIU ZHIMIN

Assignees

  • 北京车和家汽车科技有限公司

Dates

Publication Date
20260508
Application Date
20250326

Claims (10)

  1. 1. The battery cell is characterized by comprising a plurality of pole pieces, a first pole lug (3), a second pole lug (4) and an isolating film (5); The pole pieces are arranged in a stacked mode along a first direction (X), the isolating film (5) is arranged between two adjacent pole pieces, two pole pieces located at the outermost side along the first direction (X) are end pole pieces (1), the first pole lugs (3) are electrically connected with one of the end pole pieces (1), and the second pole lugs (4) are electrically connected with the other end pole piece (1).
  2. 2. The cell according to claim 1, wherein the pole pieces other than the end pole piece (1) among the plurality of pole pieces are middle pole pieces (2), active material layers are respectively arranged on two sides of the middle pole piece (2) along the first direction (X), and polarities of the active material layers arranged on two sides of the middle pole piece (2) are opposite.
  3. 3. The cell according to claim 2, wherein a plurality of the intermediate pole pieces (2) are provided, and the polarities of the active material layers facing the same side of the plurality of the intermediate pole pieces (2) are the same.
  4. 4. The cell according to claim 1, characterized in that the side of the end pole piece (1) facing the adjacent pole piece is a first side (8), the first side (8) of the end pole piece (1) is provided with an active material layer, and the polarities of the active material layers provided by the first sides (8) of the two end pole pieces (1) are opposite.
  5. 5. The cell according to claim 1, further comprising a solid electrolyte provided in a space other than the separator (5) for every adjacent two of the pole pieces.
  6. 6. The cell according to claim 5, further comprising a protective film (10); The pole pieces are stacked to form a pole piece group, the protective film (10) is coated on at least part of the peripheral outer side of the pole piece group, every two adjacent pole pieces and the protective film (10) are enclosed to form a containing cavity, and the solid electrolyte is arranged in the containing cavity.
  7. 7. The cell according to claim 6, characterized in that the protective film (10) is at least partially wrapped at the junction of the first tab (3) and one of the end pole pieces (1) and/or that the protective film (10) is at least partially wrapped at the junction of the second tab (4) and the other of the end pole pieces (1).
  8. 8. The cell according to any one of claims 1-7, wherein the pole piece comprises a current collector (11), at least one side of the current collector (11) is provided with an active material layer, and the current collectors (11) in a plurality of pole pieces are the same material.
  9. 9. The cell according to claim 8, wherein the current collector (11) comprises at least one of an aluminum foil, a titanium-based composite current collector (11), a carbon-based composite current collector (11), and/or the current collector (11) is of a porous structure.
  10. 10. A battery pack comprising a cell according to any one of claims 1-9.

Description

Battery cell and battery pack Technical Field The application belongs to the technical field of batteries, and particularly relates to a battery cell and a battery pack. Background The service life and the endurance mileage of the battery of the automobile are very key technical indexes of the electric automobile, are also the purchasing factors considered by consumers at first, and are the directions of research of most battery manufacturers, namely, how to improve the cycle life and the cost of the battery pack. The battery pack comprises an electric core, an electrode assembly in the electric core is formed by assembling positive and negative electrode plates, a diaphragm and winding or laminating plates, each electrode plate is led out of one tab, the tabs of all the positive electrode plates are integrated together to form a first tab cluster, and the tabs of all the negative electrode plates are integrated together to form a second tab cluster. However, in the battery cell of the related art, each pole piece needs to be connected with a pole lug, the process is complex, and the arrangement of more pole lugs can increase the internal resistance of the battery cell and reduce the overcurrent capacity of the battery cell. Disclosure of utility model The application aims to provide a battery cell and a battery pack, which can solve the problems of complex process of the battery cell and low overcurrent capacity of the battery cell in the prior art. In order to solve the technical problems, the application is realized as follows: In a first aspect, an embodiment of the application provides an electric core, which comprises a plurality of pole pieces, first pole lugs, second pole lugs and isolating films, wherein the pole pieces are stacked along a first direction, the isolating films are arranged between two adjacent pole pieces, the two pole pieces located at the outermost side along the first direction are end pole pieces, the first pole lugs are electrically connected with one of the end pole pieces, and the second pole lugs are electrically connected with the other end pole piece. Optionally, the pole pieces except the end pole pieces are middle pole pieces, active material layers are respectively arranged on two sides of the middle pole piece along the first direction, and polarities of the active material layers arranged on two sides of the middle pole piece are opposite. Optionally, a plurality of the middle pole pieces are arranged, and the polarities of the active material layers facing the same side of the plurality of the middle pole pieces are the same. Optionally, a side of the end pole piece facing the adjacent pole piece is a first side, the first side of the end pole piece is provided with an active material layer, and the polarities of the active material layers arranged on the first sides of the two end pole pieces are opposite. Optionally, the solid electrolyte is arranged in the space of each two adjacent pole pieces except the isolating film. Optionally, a protective film is further included; the pole pieces are stacked to form a pole piece group, the protective film is coated on at least part of the peripheral outer side of the pole piece group, every two adjacent pole pieces and the protective film are enclosed to form a containing cavity, and the solid electrolyte is arranged in the containing cavity. Optionally, the protection film is at least partially coated at the connection part of the first tab and one of the end pole pieces, and/or the protection film is at least partially coated at the connection part of the second tab and the other of the end pole pieces. Optionally, the pole piece includes a current collector, at least one side of the current collector is provided with an active material layer, and materials of the current collectors in the pole pieces are the same. Optionally, the current collector comprises at least one of an aluminum foil, a titanium-based composite current collector and a carbon-based composite current collector, and/or the current collector is of a porous structure. In a second aspect, an embodiment of the present application provides a battery pack including the battery cell according to the above embodiment. In the embodiment of the application, a plurality of pole pieces are stacked along a first direction, an isolating film is arranged between two adjacent pole pieces, two pole pieces positioned at the outermost side along the first direction are end pole pieces, a first pole lug is electrically connected with one end pole piece, and a second pole lug is electrically connected with the other end pole piece. Therefore, the complex procedure of independently welding the pole lugs on each pole piece in the traditional scheme is omitted, the assembly steps of the pole lugs are greatly reduced, the production flow is simplified, the process control difficulty caused by the alignment deviation of the pole lugs is reduced, and the production efficiency a