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EP-4738520-A1 - BATTERY CELL AND ELECTRIC DEVICE

EP4738520A1EP 4738520 A1EP4738520 A1EP 4738520A1EP-4738520-A1

Abstract

A cell and an electric device are provided. The cell includes an electrode assembly, where the electrode assembly includes a positive electrode plate, a negative electrode plate, a positive electrode tab, and a negative electrode tab. The positive electrode plate includes a positive electrode active material region, and the negative electrode plate includes a negative electrode active material region; along a width direction of the positive electrode plate, the positive electrode active material region has a first end and a second end opposite to each other, and the positive electrode tab protrudes from the first end; along a width direction of the negative electrode plate, the negative electrode active material region has a first region extending beyond the first end and a second region extending beyond the second end, the negative electrode tab is connected to the first region, a width of the first region is denoted as E, a width of the second region is denoted as C, and E > C. This enables the housing to reserve more space for the electrolyte on the tab side of the negative electrode active material region and the tab side of the positive electrode active material region without increasing the volume of the housing. In this way, the positive electrode plate and the negative electrode plate may be fully infiltrated, thereby endowing the cell with relatively good cycling performance and a relatively high volumetric energy density.

Inventors

  • JIANG, JING

Assignees

  • Xiamen Ampace Technology Limited

Dates

Publication Date
20260506
Application Date
20230630

Claims (13)

  1. A cell comprising: an electrode assembly comprising a positive electrode plate, a negative electrode plate, a positive electrode tab, and a negative electrode tab, wherein the positive electrode tab is electrically connected to the positive electrode plate, the negative electrode tab is electrically connected to the negative electrode plate, the positive electrode plate comprises a positive electrode active material region, and the negative electrode plate comprises a negative electrode active material region; along a width direction of the positive electrode plate, the positive electrode active material region has a first end and a second end opposite to each other, and the positive electrode tab protrudes from the first end; and along a width direction of the negative electrode plate, the negative electrode active material region has a first region extending beyond the first end and a second region extending beyond the second end, the negative electrode tab is connected to the first region, a width of the first region is denoted as E, a width of the second region is denoted as C, and E > C.
  2. The cell according to claim 1, wherein 1.05 ≤ E/C ≤ 10.
  3. The cell according to claim 2, wherein 1.1 ≤ E/C ≤ 4.
  4. The cell according to claim 1, wherein the cell further comprises an insulating member, wherein at least a portion of the insulating member is located between the first region and the positive electrode tab.
  5. The cell according to claim 4, wherein along the width direction of the negative electrode plate, the first region has a third end facing away from the second region, and the insulating member extends beyond the third end in a direction away from the positive electrode active material region.
  6. The cell according to claim 5, wherein along the width direction of the negative electrode plate, the insulating member has a third region extending beyond the third end, wherein a width of the third region is denoted as F, and 0 < (E + C)/2 - F ≤ 5 mm.
  7. The cell according to claim 6, wherein 0.1 mm ≤ (E + C)/2 - F ≤ 1 mm.
  8. The cell according to claim 4, wherein one end of the insulating member is in contact with the first end.
  9. The cell according to claim 1, wherein the cell further comprises a housing, the electrode assembly is accommodated in the housing, the housing has a first wall and a second wall arranged opposite to each other, the first end faces the first wall, and the second end faces the second wall; and a distance between the first region and the first wall is denoted as K 1 , a distance between the second region and the second wall is denoted as K 2 , and K 1 > K 2 .
  10. The cell according to claim 9, wherein the cell further comprises an insulating member, wherein at least a portion of the insulating member is located between the first region and the positive electrode tab; and the insulating member has a fourth end facing the first wall, a distance between the fourth end and the first wall is denoted as K 3 , and K 3 > K 2 .
  11. The cell according to claim 1, wherein the electrode assembly further comprises a separator, wherein the separator is configured to separate the positive electrode plate and the negative electrode plate, along the width direction of the positive electrode plate, a width of a portion of the separator extending beyond the first end is denoted as L 1 , a width of a portion of the separator extending beyond the second end is denoted as L 2 , and 0 < L 1 - L 2 ≤ 8 mm.
  12. The cell according to claim 11, wherein 1 mm ≤ L 1 - L 2 ≤ 3 mm.
  13. An electric device comprising the cell according to any one of claims 1 to 12.

Description

TECHNICAL FIELD The present application relates to the field of battery technologies, and specifically, to a cell and an electric device. BACKGROUND Cells are widely applied in fields such as portable electronic devices, electric vehicles, power tools, unmanned aerial vehicles, and energy storage devices. With the increasingly wide and complex range of applications, higher requirements have been placed on the energy density of cells. SUMMARY Some embodiments of the present application provide a cell and an electric device to enable the cell to have a high volumetric energy density. According to a first aspect, an embodiment of the present application provides a cell, where the cell includes an electrode assembly, the electrode assembly includes a positive electrode plate, a negative electrode plate, a positive electrode tab, and a negative electrode tab, the positive electrode tab is electrically connected to the positive electrode plate, the negative electrode tab is electrically connected to the negative electrode plate, the positive electrode plate includes a positive electrode active material region, and the negative electrode plate includes a negative electrode active material region; along a width direction of the positive electrode plate, the positive electrode active material region has a first end and a second end opposite to each other, and the positive electrode tab protrudes from the first end; and along a width direction of the negative electrode plate, the negative electrode active material region has a first region extending beyond the first end and a second region extending beyond the second end, the negative electrode tab is connected to the first region, a width of the first region is denoted as E, a width of the second region is denoted as C, and E > C. In the above technical solution, the positive electrode tab protrudes from the first end of the positive electrode active material region, the first end corresponds to a tab side of the positive electrode active material region, and the second end corresponds to a non-tab side of the positive electrode active material region; the first region of the negative electrode active material region extends beyond the first end, the negative electrode tab is connected to the first region, the first region corresponds to a tab side of the negative electrode active material region, and the second region corresponds to a non-tab side of the negative electrode active material region; and the width E of the first region and the width C of the second region meet E > C, to be specific, the width of the portion of the negative electrode active material region on the tab side that extends beyond the tab side of the positive electrode active material region is greater than the width of the portion of the negative electrode active material region on the non-tab side that extends beyond the non-tab side of the positive electrode active material region. In this way, the position of the electrode assembly within a housing of the cell may be adjusted, such that along the width direction of the positive electrode plate, a distance between the first end and a wall portion of the housing is greater than a distance between the second end and a wall portion of the housing, thereby reserving more space for the electrolyte on the tab side of the negative electrode active material region and the tab side of the positive electrode active material region without increasing the volume of the housing. In this way, the positive electrode plate and the negative electrode plate may be fully infiltrated, thereby endowing the cell with relatively good cycling performance and endowing the cell with a relatively high volumetric energy density. In some embodiments of the first aspect of the present application, 1.05 ≤ E/C ≤ 10. In the above technical solution, if E/C < 1.05, the degree to which the width of the portion of the negative electrode active material region on the tab side extending beyond the tab side of the positive electrode active material region is greater than the width of the portion of the negative electrode active material region on the non-tab side extending beyond the non-tab side of the positive electrode active material region is relatively small. Consequently, a distance between the first end and the wall portion of the housing is relatively small, and space reserved in the housing for the electrolyte on the tab side of the negative electrode active material region and the tab side of the positive electrode active material region is relatively small, increasing the risk that the positive electrode plate and the negative electrode plate may not be fully infiltrated. If E/C > 10, the width of the portion of the negative electrode active material region on the tab side extending beyond the tab side of the positive electrode active material region is much greater than the width of the portion of the negative electrode active material region on the non-tab side ex