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EP-4741751-A1 - HEAT SPREADERS, BATTERIES AND BATTERY PACKS

EP4741751A1EP 4741751 A1EP4741751 A1EP 4741751A1EP-4741751-A1

Abstract

A heat spreader includes a first plate, a second plate and a plurality of protrusions. The first plate is configured to fit against at least one side surface of a cell. The second plate is hermetically connected to the first plate to form an enclosed space filled with a liquid medium. The protrusions are disposed between the first plate and the second plate and dispersedly arranged in the enclosed space. Some of the protrusions are arranged at intervals in a first direction to form a protrusion group, and two parts of the protrusions respectively belonging to two adjacent protrusion groups are at least partially staggered in a second direction different from the first direction.

Inventors

  • GUO, Jiahao
  • SUN, FEI
  • TAN, Xianyang
  • LEI, YU
  • GAN, Junchong
  • YUAN, Dingding
  • CHEN, Jiujiang

Assignees

  • Eve Power Co., Ltd.

Dates

Publication Date
20260513
Application Date
20250815

Claims (15)

  1. A heat spreader (100), comprising: a first plate (110) configured to fit against at least one side surface of a cell (200); a second plate (120) hermetically connected to the first plate (110) to form an enclosed space (130), wherein the enclosed space (130) is filled with a liquid medium; and a plurality of protrusions (140) disposed between the first plate (110) and the second plate (120) and dispersedly arranged in the enclosed space (130), wherein the protrusions (140) comprise a plurality of protrusion groups (145), each of the protrusion groups (145) comprises ones of the protrusions (140) sequentially arranged at intervals in a first direction, and two parts of the protrusions (140) respectively belonging to two adjacent ones of the protrusion groups (145) are at least partially staggered in a second direction different from the first direction.
  2. The heat spreader (100) according to claim 1, wherein the second plate (120) is recessed toward the first plate (110) to form the protrusions (140).
  3. The heat spreader (100) according to claim 1 or 2, wherein the second direction is perpendicular to the first direction; and in the second direction, an orthographic projection of one of the protrusions (140) belonging to one of the two adjacent ones of the protrusion groups (145) on another one of the two adjacent ones of the protrusion groups (145) is located at an area between two adjacent ones of the protrusions (140) belonging to the another one of the two adjacent ones of the protrusion groups (145).
  4. The heat spreader (100) according to claim 1 or 2, wherein the second direction is perpendicular to the first direction; and in the second direction, an orthographic projection of one of the protrusions (140) belonging to one of the two adjacent ones of the protrusion groups (145) on another one of the two adjacent ones of the protrusion groups (145) at least covers an area between two adjacent ones of the protrusions (140) belonging to the another one of the two adjacent ones of the protrusion groups (145).
  5. The heat spreader (100) according to any one of claims 1-4, wherein the protrusions (140) comprise a plurality of first protrusions (141) and a plurality of second protrusions (142); the second protrusions (142) comprise a plurality of second protrusion groups (144), and each of the second protrusion groups (144) comprises ones of the second protrusions (142) arranged at intervals in the first direction; and at least one of the first protrusions (141) is arranged between two adjacent ones of the second protrusion groups (144) to extend in the first direction.
  6. The heat spreader (100) according to any one of claims 1-4, wherein the protrusions (140) comprise a plurality of first protrusions (141) each extending in the first direction, and an orthographic projection of each of the first protrusions (141) on the second plate (120) has an elongated strip shape; and the first protrusions (141) comprise a plurality of first protrusion groups (143), each of the first protrusion groups (143) comprises ones of the first protrusions (141) arranged at intervals in the first direction, and two parts of the first protrusions (141) respectively belonging to two adjacent ones of the first protrusion groups (143) are at least partially staggered in the second direction.
  7. The heat spreader (100) according to claim 6, wherein the protrusions (140) further comprise a plurality of second protrusions (142), the second protrusions (142) comprise a plurality of second protrusion groups (144), and each of the second protrusion groups (144) comprises ones of the second protrusions (142) arranged at intervals in the first direction; one of the second protrusion groups (144) is located between two of the first protrusion groups (143); and two parts of the second protrusions (142) respectively belonging to two adjacent ones of the second protrusion groups (144) are at least partially staggered in the second direction.
  8. The heat spreader (100) according to claim 5 or 7, wherein each of the first protrusions (141) has a shape different from a shape of any of the second protrusions (142).
  9. The heat spreader (100) according to any one of claims 5 and 7-8, wherein at least one of the second protrusion groups (144) is disposed between every two of the first protrusion groups (143).
  10. The heat spreader (100) according to any one of claims 5 and 7-9, wherein ones of the second protrusions (142) are arranged between one of the first protrusion groups (143) and an edge of the second plate (120).
  11. The heat spreader (100) according to any one of claims 5-10, wherein the first plate (110) is welded to the second plate (120) at a position of at least one of the first protrusions (141); and/or a periphery of the first plate (110) is welded to a periphery of the second plate (120).
  12. The heat spreader (100) according to any one of claims 1-11, wherein a periphery of the second plate (120) is provided with a flange portion (150) protruding toward the first plate (110), and the flange portion (150) is welded to the first plate (110).
  13. A battery, comprising: at least one cell (200); and at least one heat spreader (100) according to any one of claims 1-12, wherein the first plate (110) of each of the at least one heat spreader (100) fits against one of the at least one cell (200).
  14. The battery according to claim 13, wherein the at least one cell (200) comprises two cells (200), and the at least one heat spreader (100) comprises one heat spreader (100) arranged between the two cells (200); or the at least one cell (200) comprises two cells (200), and the at least one heat spreader (100) comprises two heat spreaders (100) arranged between the two cells (200) to respectively fit against the two cells (200); or the at least one cell (200) comprises two cells (200), the at least one heat spreader (100) comprises two heat spreaders (100), one of the two heat spreaders (100) is arranged outside the two cells (200), and another one of the two heat spreaders (100) is arranged between the two cells (200); or the at least one cell (200) comprises two cells (200), the at least one heat spreader (100) comprises two heat spreaders (100), and the two cells (200) are arranged between the two heat spreaders (100).
  15. A battery pack, comprising the battery according to claim 13 or 14.

Description

TECHNICAL FIELD The present application relates to battery heat dissipation technologies, and in particular to heat spreaders, batteries and battery packs. BACKGROUND Lithium-ion batteries widely used in new energy vehicles, especially pure electric vehicles, need to meet the requirements of high energy density and high power density, which pose severe challenges to the thermal management of large power battery packs. For a popular battery cell with a square housing, a water cooling plate may be provided at the bottom of the cell for heat dissipation. However, this manner has limitations such as small heat dissipation area and large temperature difference between cells, and thus it is difficult to meet the heat dissipation requirements of higher energy density batteries and higher charge and discharge rate conditions in the future. On the other hand, a heat spreader may be provided to balance the temperature of the battery. Copper columns may be disposed between upper and lower copper sheets of the heat spreader for support. When the heat is transferred from the heat source to the evaporation area, the coolant in the cavity begins to vaporize, after being heated in a low vacuum environment, to absorb the heat energy and expand rapidly in volume, so that the gas-phase cooling medium fills the entire cavity. When entering a relatively cold area, the gas-phase cooling medium will condense, through which the heat accumulated during evaporation will be released. The condensed coolant will return to the evaporation area through the micro-structured capillary channels. Thus, heat dissipation may be achieved. However, the gas-phase cooling medium may be unevenly dispersed in the cavity and there may be less gas-phase cooling medium in some areas, which will affect the heat spread effect, so that there may still be large temperature difference between cells of the battery pack. SUMMARY According to some embodiments of the present application, a heat spreader includes a first plate, a second plate and a plurality of protrusions. The first plate is configured to fit against at least one side surface of a cell. The second plate is hermetically connected to the first plate to form an enclosed space filled with a liquid medium. The protrusions are disposed between the first plate and the second plate and dispersedly arranged in the enclosed space. The protrusions include a plurality of protrusion groups, and each of the protrusion groups includes ones of the protrusions sequentially arranged at intervals in a first direction. Two parts of the protrusions respectively belonging to two adjacent protrusion groups are at least partially staggered in a second direction different from the first direction. According to some embodiments of the present application, a battery includes a cell and the above heat spreader. According to some embodiments of the present application, a battery pack includes the above battery. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an axonometric drawing of a heat spreader according to some embodiments of the present application.FIG. 2 is another axonometric drawing of a heat spreader according to some embodiments of the present application.FIG. 3 schematically shows part of a heat spreader according to some embodiments of the present application.FIG. 4 is a cross-sectional view of a heat spreader according to some embodiments of the present application.FIG. 5 is an enlarged view of part A in FIG. 4.FIG. 6 is an enlarged view of part B in FIG. 4.FIG. 7 is a stereoscopic view of part of a second plate of a heat spreader according to some embodiments of the present application.FIG. 8 is an exploded view of a first structure of a battery according to some embodiments of the present application.FIG. 9 is an exploded view of a second structure of a battery according to some embodiments of the present application.FIG. 10 is an exploded view of a third structure of a battery according to some embodiments of the present application.FIG. 11 is an exploded view of a fourth structure of a battery according to some embodiments of the present application.FIG. 12 is an exploded view of a fifth structure of a battery according to some embodiments of the present application. DETAILED DESCRIPTION Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The embodiments are described for illustrative purposes only and are not intended to limit the present application. As shown in FIG. 1, FIG. 2, FIG. 4, FIG. 5 and FIG. 6, a heat spreader 100 includes a first plate 110, a second plate 120 and a plurality of protrusions 140 according to some embodiments of the present application. The first plate 110 and the second plate 120 are made of metal materials, such as copper, aluminum, stainless steel or metal compounds. The first plate 110 is configured to fit against at least one side surface of the cell 200. The second plate 120 and the first plate 110 are her