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EP-4742424-A1 - ELECTRODE PLATE, CELL AND BATTERY MODULE

EP4742424A1EP 4742424 A1EP4742424 A1EP 4742424A1EP-4742424-A1

Abstract

An electrode plate, a cell and a battery module are provided. The electrode plate includes an electrode plate body (1) and N tabs (2). The electrode plate body (1) has a length direction and a width direction perpendicular to each other. The N tabs (2) are arranged at intervals in the length direction of the electrode plate body (1), the bottom edge widths of the N tabs (2) gradually decrease and then increase in the length direction of the electrode plate body (1), and the N tabs (2) overlap after the electrode plate body (1) is wound. N is a positive integer greater than or equal to 3.

Inventors

  • YANG, XIN
  • CHEN, LIQUAN
  • SU, BIN

Assignees

  • Eve Power Co., Ltd.

Dates

Publication Date
20260513
Application Date
20240930

Claims (11)

  1. An electrode plate, comprising: an electrode plate body (1) having a length direction and a width direction which are perpendicular to each other; and N tabs (2) arranged at intervals in the length direction of the electrode plate body (1), wherein bottom edge widths of the N tabs (2) decrease and then increase sequentially in the length direction of the electrode plate body (1), and the N tabs (2) overlap after the electrode plate body (1) is wound; wherein N is a positive integer greater than or equal to 3.
  2. The electrode plate according to claim 1, wherein the N tabs (2) comprise a middle tab and two end tabs located at two ends respectively; in response to N being an odd number, an ((N+1)/2) th tab (2) is the middle tab; in response to N being an even number, an (N/2) th tab (2) and an ((N/2)+1) th tab (2) are middle tabs; and among the N tabs (2), a bottom edge width of the middle tab is the smallest, and bottom edge widths of the two end tabs are consistent.
  3. The electrode plate according to claim 2, wherein each of the bottom edge widths of the two end tabs is a, and the bottom edge width of the middle tab is b, wherein b < a; in response to N being the odd number, a bottom edge width difference Δw between two adjacent tabs (2) of the N tabs (2) is equal to 2(a - b)/(N - 1); in response to N being the even number, a bottom edge width difference Δw between the two middle tabs (2) is equal to 0, and each of a bottom edge width difference Δw between non-middle tabs and a bottom edge width difference Δw between a non-middle tab and a middle tab is equal to 2(a - b)/(N - 2); wherein the non-middle tab is a tab other than the middle tabs among the N tabs (2).
  4. The electrode plate according to claim 3, wherein each of the bottom edge widths of the two end tabs and the bottom edge width of the middle tab satisfy: b ≥ a/2.
  5. The electrode plate according to claim 1, wherein a bottom edge width difference Δw between two adjacent tabs (2) of the N tabs (2) is in a range of 0 mm to 4 mm.
  6. The electrode plate according to any one of claims 1 to 5, wherein each of the N tabs (2) is provided with an ultrasonic solder mark, the N tabs (2) are each fixedly connected at the ultrasonic solder mark, a dimension of the ultrasonic solder mark in the length direction of the electrode plate body (1) is L, and a bottom edge width of a tab (2) with a smallest bottom edge width among the N tabs (2) is 0.8 mm to 2 mm larger than L.
  7. The electrode plate according to any one of claims 1 to 5, wherein heights of the N tabs (2) are uniform; or heights of the N tabs (2) gradually increase in the length direction of the electrode plate body (1).
  8. The electrode plate according to any one of claims 1 to 5, wherein center-to-center distances between two adjacent tabs (2) of the N tabs (2) gradually increase in the length direction of the electrode plate body (1).
  9. The electrode plate according to any one of claims 1 to 5, wherein the N tabs (2) are trapezoidal, and lower bottom edges of the N tabs (2) are connected to the electrode plate body (1), and the bottom edge widths are widths of the lower bottom edges of the N tabs.
  10. A cell, comprising a housing and a jelly roll component (100) disposed within the housing, wherein the jelly roll component (100) comprises a first separator, a positive electrode plate, a second separator, and a negative electrode plate which are stacked in sequence, and the positive electrode plate and the negative electrode plate are each the electrode plate according to any one of claims 1 to 9.
  11. A battery module, comprising a cells contact system, CCS, assembly and a plurality of cells according to claim 10, wherein the CCS assembly is configured to collect voltage signals and temperature signals of the plurality of cells.

Description

This application claims priority to Chinese Patent Application No. 202420954961.5 filed with the China National Intellectual Property Administration (CNIPA) on April 30, 2024, the disclosure of which is incorporated herein by reference in its entirety. TECHNICAL FIELD This application relates to the field of battery technology, specifically, to an electrode plate, a cell and a battery module. BACKGROUND Winding electrode plates to manufacture a battery is advantageous for increasing production speed and reducing production costs. To increase battery energy density, multi-tab electrode plates are often used for winding. In the process of winding multi-tab electrode plates, errors in dimensional accuracy of winding needle processing and thickness errors in the incoming electrode plate material may cause tab misalignment in a wound state. Severe misalignment may adversely affect subsequent ultrasonic soldering of the tabs to the adapters and cell assembly, increase defects during production, and compromise product performance. In a multi-tab wound cell disclosed in related art, the multiple tabs gradually decrease in width from the winding initial end to the winding tail end. After being wound, the tabs with progressively reduced widths can prevent adverse impact on the tab misalignment and improve alignment of the multiple tabs. Technical Problem However, the above solution has the following drawbacks: due to the gradually decreasing tab widths, when there are a large number of tabs, one or more tabs at the winding tail end may be too narrow. After the electrode plate is wound, the overlapping tabs must be ultrasonically soldered. The ultrasonic solder marks formed on the tabs must meet certain dimensional requirements to ensure solder stability and current carrying capacity at the tab locations. In the above solution, the width of the tab at the winding tail end may be less than the designed solder mark length, resulting in poor soldering and seriously affecting battery performance. Therefore, an electrode plate, a cell and a battery module that can avoid this problem are in urgent demand. Technical Solution In a first aspect, an electrode plate is provided according to the present application, which includes an electrode plate body and N tabs. The electrode plate body has a length direction and a width direction which are perpendicular to each other. The N tabs are arranged at intervals in the length direction of the electrode plate body, bottom edge widths of the N tabs decrease and then increase sequentially in the length direction of the electrode plate body, and the N tabs overlap after the electrode plate body is wound. N is a positive integer greater than or equal to 3. For example, the N tabs include a middle tab and two end tabs located at two ends respectively. In response to N being an odd number, an ((N+1)/2)th tab is the middle tab. In response to N being an even number, an (N/2)th tab and an ((N/2)+1)th tab are middle tabs. Among the N tabs, a bottom edge width of the middle tab is the smallest, and bottom edge widths of the two end tabs are the same. For example, the bottom edge width of each end tab is a, and the bottom edge width of the middle tab is b, where b < a. In response to N being the odd number, the bottom edge width difference Δw between two adjacent tabs is equal to 2(a - b)/(N - 1). In response to N being an even number, the bottom edge width difference Δw between the two middle tabs is equal to 0, and the bottom edge width difference Δw between non-middle tabs and the bottom edge width difference Δw between a non-middle tab and the middle tab are each equal to 2(a - b)/(N - 2). The non-middle tab is a tab other than the middle tabs. For example, the bottom edge width a of each end tab and the bottom edge width b of the middle tab satisfy: b ≥ a/2. For example, the bottom edge width difference Δw between two adjacent tabs is in the range of 0 mm to 4 mm. For example, each of the N tabs is provided with an ultrasonic solder mark, the N tabs are fixedly connected at the ultrasonic solder marks, the dimension of the ultrasonic solder mark in the length direction of the electrode plate body is L, and the bottom edge width of the tab with the smallest bottom edge width is 0.8 mm to 2 mm larger than L. For example, heights of the N tabs are uniform. Alternatively, the heights of the N tabs gradually increase in the length direction of the electrode plate body. For example, the center-to-center distances between two adjacent tabs gradually increase in the length direction of the electrode plate body. For example, the tab is trapezoidal, and a lower bottom edge of the tab is connected to the electrode plate body, and the bottom edge width is the width of the lower bottom edge of the tab. In a second aspect, the present application provides a cell including a housing and a jelly roll component disposed within the housing. The jelly roll component includes a first separator, a positive ele