Search

CN-122003779-A - Production of battery cells via tab extensions

CN122003779ACN 122003779 ACN122003779 ACN 122003779ACN-122003779-A

Abstract

The invention relates to a method for producing a battery cell having at least two battery poles arranged on opposite sides, wherein at least one electrode group is provided, the electrode group having a plurality of anode foils and cathode foils, which are separated from one another by a separator foil, the anode foils having anode lugs at their ends, the cathode foils having cathode lugs at their ends, the anode lugs of the anode foils being bundled on a first side and the cathode lugs of the cathode foils being bundled on a second side of the electrode group, the bundled anode lugs and/or cathode lugs being electrically conductively connected at least in part to at least one lug extension, at least one electrode group provided with at least one lug extension being inserted into a battery housing, the anode lugs being electrically conductively connected directly or indirectly to a current collector of a first battery pole via the at least one lug extension, and the cathode lugs being electrically conductively connected directly or indirectly to a current collector of a second battery pole via the at least one lug extension, and wherein the battery housing is closed by the first battery pole and the second battery pole. Furthermore, the invention relates to a battery cell.

Inventors

  • JURGEN GRAF

Assignees

  • 动力电池集团有限公司

Dates

Publication Date
20260508
Application Date
20241014
Priority Date
20231013

Claims (16)

  1. 1. A method for producing a battery cell (100), the battery cell (100) having at least two battery poles (101, 102) arranged on opposite sides (S1, S2), wherein Providing at least one electrode group (10) having a plurality of anode foils (11) and cathode foils (12), the anode foils (11) and cathode foils (12) being separated from each other by a separator foil (13), wherein the anode foils (11) have anode tabs (21) at their ends and the cathode foils (12) have cathode tabs (22) at their ends, the anode tabs (21) of the anode foils (11) being bundled on a first side (S1) of the electrode group (10) and the cathode tabs (22) of the cathode foils (12) being bundled on a second side (S2) of the electrode group (10), The anode tab (21) and/or the cathode tab (22) are electrically conductively connected to at least one tab extension (23) at least in a partial region, Inserting at least one electrode group (10) provided with at least one tab extension (23) into a battery housing (30), -The anode tab (21) is electrically conductively connected directly to the current collector (111) of the first battery post (101) without a tab extension (23) or indirectly to the current collector (111) of the first battery post (101) via the at least one tab extension (23), and-the cathode tab (22) is electrically conductively connected directly to the current collector of the second battery post (102) without a tab extension (23) or indirectly to the current collector of the second battery post (102) via the at least one tab extension (23), -Said battery housing (30) being closed by said first battery post (101) and said second battery post (102), The invention is characterized in that the tab extension (23) and/or at least one current collector (111) has at least one alignment aid (26), the alignment aid (26) being used to align the tab extension (23) with the current collector (111) of the first battery post (101) and/or with the current collector of the second battery post (102), wherein the tab extension (23) which is directly or indirectly connected to the anode tab (21) and/or cathode tab (22) is positioned on the current collector (111) of the first battery post (101) and/or on the current collector of the second battery post (102) by means of the alignment aid (26).
  2. 2. Method according to claim 1, wherein at least one tab extension (23, 24) is provided by a solid material or by a plurality of material layers (25) which are connected or disconnected to each other at least in partial areas to extend the anode tab (21) and/or cathode tab (22).
  3. 3. Method according to claim 2, wherein at least one tab extension (24) is formed in the region of at least one bending point (B) from a plurality of material layers (25) which are not connected in the region of the bending point (B).
  4. 4. A method according to any one of claims 1 to 3, wherein the anode tab (21) and/or the cathode tab (22) are centrally or eccentrically bundled along the width direction (B) of the battery cell (100).
  5. 5. Method according to any one of claims 1 to 4, wherein a bundle of anode tabs (21 ') and/or a bundle of cathode tabs (22') are combined into a stack and fixed in a bundle by being connected to the at least one tab extension (23) and/or by introducing at least one connection point (V).
  6. 6. Method according to any one of claims 1 to 5, wherein the bundled anode tabs (21 ') and/or the bundled cathode tabs (22') are electrically conductively connected at least in partial regions to at least one foil-like or plate-like and/or pre-bent tab extension (24).
  7. 7. Method according to claim 6, wherein at least one pre-bent tab extension (23) is bent or folded into an arc or S-shape or U-shape, in particular by plastic deformation, before being electrically connected to the anode tab (21) and/or the cathode tab (22).
  8. 8. Method according to claim 6 or 7, wherein at least one pre-bent tab extension (23) is elastically deformed flat at least in a partial region to form an electrical connection with the current collector (111).
  9. 9. Method according to any one of claims 1 to 8, wherein at least two mutually adjacent electrode groups (10) are provided, wherein the bundled anode tabs (21 ') and/or cathode tabs (22') of a first electrode group (10) and a second electrode group are electrically conductively connected to at least one tab extension (23) at least in partial regions, wherein the anode tabs (23) of the first electrode group (10) are connected to the anode tabs of the second electrode group in an offset manner or with the tab extension (23) overlapping each other, and/or wherein the cathode tabs (22) of the first electrode group (10) are offset with respect to the cathode tabs of the second electrode group in at least one spatial direction (B, H, L) or are connected to the tab extension (23) in an overlapping manner.
  10. 10. The method according to any one of claims 1 to 9, wherein a tab extension (23) for an anode tab (21) is provided by a material composition of the anode tab (21) and a tab extension (23) for a cathode tab (22) is provided by a material composition of the cathode tab (22).
  11. 11. Method according to any one of claims 1 to 10, wherein the anode tab (21) and/or the cathode tab (22) and/or the at least one tab extension (23) are aligned parallel to the surface of at least one current collector (111) and pressed against the current collector (111) for electrical connection, wherein after the electrical connection the first battery post (101) and/or the second battery post (102) is folded in the direction of the battery housing (30), in particular at an angle of 90 °, to enclose the internal volume (33) of the battery housing (30).
  12. 12. Method according to claim 11, wherein at least one tab extension (23) is elastically and/or plastically deformed before and/or during folding of the battery post (101, 102).
  13. 13. The method according to claim 1, wherein the at least one alignment aid (26) is configured as at least one through hole configured to mate with at least one pin and/or protrusion of the current collector (111), wherein the at least one tab extension (23) positioned on the current collector (111) is connected in material-fit with the current collector (111) at the alignment aid (26) and/or at a location spaced apart from the alignment aid (26).
  14. 14. The method according to any one of claims 9 to 13, wherein the tab extension (23) is positioned at an angle relative to the first side of a first angle (α1) and an anode tab (21 ') of the first electrode group (10) is electrically connected to the tab extension (23), wherein the tab extension (23) is positioned relative to the first side of the first angle (α1) or a second angle (α2) and connected to an anode tab (21') of the second electrode group, wherein the tab extension (23) is rotated relative to the first side of the second angle (α2) or a third angle (α3) and positioned at a current collector (111) of the first battery post (101) and connected to the current collector (111).
  15. 15. The method according to any one of claims 9 to 14, wherein the tab extension (23) is positioned at an angle of a first angle (α1) with respect to the second side and the cathode tab (22 ') of the first electrode group (10) is electrically conductive connected to the tab extension (23), wherein the tab extension (23) is positioned at the first angle (α1) or a second angle (α2) with respect to the second side and connected to the cathode tab (22') of the second electrode group, wherein the tab extension (23) is rotated at the second angle (α2) or a third angle (α3) with respect to the second side and positioned at a current collector of the second battery post (102) and connected to the current collector of the second battery post (102).
  16. 16. A battery cell (100) having at least one electrode group (10), the electrode group (10) having a plurality of anode foils (11) and cathode foils (12), the anode foils (11) and cathode foils (12) being separated from each other by a separator foil (13), wherein the anode foils (11) have an anode tab (21) on a first side (S1) and the cathode foils (12) have a cathode tab (22) on a second side (S2), and the anode foils (11) and cathode foils (12) are arranged in a battery housing (30), wherein the anode tab (21) is directly electrically connected to a current collector (111) of a first battery post (101) without a tab extension (23) or indirectly connected to a current collector (111) of a first battery post (101) via a tab extension (23), and/or the cathode tab (22) is directly electrically connected to a current collector (102) of a second battery post (102) without a tab extension (23) and the second battery post (102) is electrically connected to the second battery post (102) via a tab extension (23) which is configured to the second battery post (102), the tab extension (23) and/or at least one current collector (111) has at least one alignment aid (26), wherein the tab extension (23) which is directly or indirectly connected to the anode tab (21) and/or the cathode tab (22) is positioned on the current collector (111) of the first cell terminal (101) and/or on the current collector of the second cell terminal (102) by means of the alignment aid (26).

Description

Production of battery cells via tab extensions The invention relates to a method for producing a battery cell equipped with at least two battery poles arranged on opposite sides, wherein at least one electrode group having a plurality of anode foils and cathode foils is placed in a battery housing, the anode foils and cathode foils being separated from each other by a separator foil. The invention also relates to a battery cell. In addition to so-called pouch cells with flexible or foil-like cell housings, hard-shell cells are also known. Such cells have a rigid metal housing and may be prismatic in geometry or in the form of circular cells. The respective battery post is positioned externally in the form of a protrusion at a so-called terminal of the battery cell to achieve a simplified electrical connection. The battery post is typically integrated into a battery cover of the battery cell, which encloses the interior volume of the battery housing. The cell covers of the battery cells are typically made of metal, such as aluminum, stainless steel, or steel with a nickel coating. Battery poles are inserted in an insulated manner relative to the battery cover, and are connected to a current collector. The battery poles are electrically connected externally and with a current collector facing the internal volume of the battery housing. In electrochemical energy storage systems, such as lithium ion batteries, an electrode assembly is arranged in the interior volume of the battery housing, the electrode assembly consisting of alternating anode layers, cathode layers and separator layers. Such anode and cathode foils may be formed by winding or stacking and positioned in the interior volume of the battery case for end use by a user. As part of the cell production process, the respective anode and cathode foils must be attached to the cell posts. For this purpose, the anode tab and the cathode tab serve as connection lines between the battery post and the anode foil or the cathode foil. On the cell side, the uncoated ends of the copper carrier foil of the anode foil and the aluminum carrier foil of the cathode foil, which protrude from the electrode assembly, are typically welded to two current collectors. In order to provide the best tool path for welding to the current collector, the anode tab and the cathode tab must be designed to have excess lengths. This excess length results in the use of electrodes with wide uncoated areas and increases material requirements and scrap. The electrodes are typically manufactured as continuous strips. The active coating on the carrier foil is compacted between the roller pairs by means of a calender and then the anode foil or the cathode foil is punched out. Due to the required excess length, wide, uncoated areas of carrier film are provided, which areas may be particularly prone to deformation during calendering. The object of the present invention is therefore to create a method for producing a battery cell, in which material waste is reduced and the connection of the tab to the current collector is simplified. This object is achieved by the features specified in claim 1. Further advantageous embodiments of the invention are part of the dependent claims. According to one aspect of the present invention, there is provided a method of manufacturing a battery cell provided with at least two battery poles arranged on opposite sides. The battery post may be pointed or oriented in two opposite directions. In one step, at least one electrode set is provided, the electrode set having a plurality of anode foils and cathode foils, the anode foils and cathode foils being separated from each other by a separator foil. The at least one electrode group may be designed in a folded or stacked form. In other words, the anode foil, cathode foil and separator foil may be cut to shape, placed on top of each other or provided in the form of long strip windings. The anode foil has an anode tab at an end and the cathode foil has a cathode tab at an end. The anode tab and the cathode tab may protrude from edges of the cut or wound anode foil and cathode foil. Advantageously, the anode tabs of the anode foil are bundled or aligned on a first side and the cathode tabs of the cathode foil are bundled or aligned on a second side of the electrode set. In a further step, the bundled anode tab and/or cathode tab is electrically conductively connected to at least one tab extension at least in a partial region. Only the anode tab, only the cathode tab, or both the cathode tab and the anode tab may be extended by one or more tab extensions. The anode tab or cathode tab may be in the form of a so-called flag-shaped tab group and may be flexibly extended as required by a tab extension or busbar welded to the edge of the anode tab or cathode tab of the electrode group and forming a connection with the current collector of the first and/or second battery post. This measure may reduce scrap of the anode foil an