US-20260128409-A1 - HEAT SPREADERS, BATTERIES AND BATTERY PACKS

US20260128409A1US 20260128409 A1US20260128409 A1US 20260128409A1US-20260128409-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

Jiahao Guo
Fei Sun
Xianyang TAN
Yu Lei
Junchong GAN
Dingding Yuan
Jiujiang CHEN

Assignees

Eve Power Co., Ltd.

Dates

Publication Date: 20260507
Application Date: 20251105
Priority Date: 20241106

Claims (20)

1 . A heat spreader, comprising: a first plate configured to fit against at least one side surface of a cell; a second plate hermetically connected to the first plate to form an enclosed space, wherein the enclosed space is filled with a liquid medium; and a plurality of protrusions disposed between the first plate and the second plate and dispersedly arranged in the enclosed space, wherein the protrusions comprise a plurality of protrusion groups, each of the protrusion groups comprises ones of the protrusions sequentially arranged at intervals in a first direction, and two parts of the protrusions respectively belonging to two adjacent ones of the protrusion groups are at least partially staggered in a second direction different from the first direction.
2 . The heat spreader according to claim 1 , wherein the second plate is recessed toward the first plate to form the protrusions.
3 . The heat spreader according to claim 1 , wherein the second direction is perpendicular to the first direction; and in the second direction, an orthographic projection of one of the protrusions belonging to one of the two adjacent ones of the protrusion groups on another one of the two adjacent ones of the protrusion groups is located at an area between two adjacent ones of the protrusions belonging to the another one of the two adjacent ones of the protrusion groups.
4 . The heat spreader according to claim 1 , wherein the second direction is perpendicular to the first direction; and in the second direction, an orthographic projection of one of the protrusions belonging to one of the two adjacent ones of the protrusion groups on another one of the two adjacent ones of the protrusion groups at least covers an area between two adjacent ones of the protrusions belonging to the another one of the two adjacent ones of the protrusion groups.
5 . The heat spreader according to claim 1 , wherein the protrusions comprise a plurality of first protrusions and a plurality of second protrusions; the second protrusions comprise a plurality of second protrusion groups, and each of the second protrusion groups comprises ones of the second protrusions arranged at intervals in the first direction; and at least one of the first protrusions is arranged between two adjacent ones of the second protrusion groups to extend in the first direction.
6 . The heat spreader according to claim 1 , wherein the protrusions comprise a plurality of first protrusions each extending in the first direction, and an orthographic projection of each of the first protrusions on the second plate has an elongated strip shape; and the first protrusions comprise a plurality of first protrusion groups, each of the first protrusion groups comprises ones of the first protrusions arranged at intervals in the first direction, and two parts of the first protrusions respectively belonging to two adjacent ones of the first protrusion groups are at least partially staggered in the second direction.
7 . The heat spreader according to claim 6 , wherein the protrusions further comprise a plurality of second protrusions, the second protrusions comprise a plurality of second protrusion groups, and each of the second protrusion groups comprises ones of the second protrusions arranged at intervals in the first direction; one of the second protrusion groups is located between two of the first protrusion groups; and two parts of the second protrusions respectively belonging to two adjacent ones of the second protrusion groups are at least partially staggered in the second direction.
8 . The heat spreader according to claim 7 , wherein each of the first protrusions has a shape different from a shape of any of the second protrusions.
9 . The heat spreader according to claim 7 , wherein at least one of the second protrusion groups is disposed between every two of the first protrusion groups.
10 . The heat spreader according to claim 7 , wherein ones of the second protrusions are arranged between one of the first protrusion groups and an edge of the second plate.
11 . The heat spreader according to claim 7 , wherein an orthographic projection of each of the second protrusions on the second plate has a circular shape.
12 . The heat spreader according to claim 11 , wherein the circular shape has a diameter of 2.5 mm.
13 . The heat spreader according to claim 7 , wherein each of the second protrusions has a height H 2 , and 0.3 mm≤H 2 ≤0.6 mm.
14 . The heat spreader according to claim 6 , wherein each of the first protrusions has a length L, and 10 mm≤L≤60 mm; and/or each of the first protrusions has a width S, and 1.5 mm≤S≤6 mm; and/or each of the first protrusions has a height H 1 , and 0.3 mm≤H 1 ≤0.6 mm.
15 . The heat spreader according to claim 6 , wherein the first plate is welded to the second plate at a position of at least one of the first protrusions; and/or a periphery of the first plate is welded to a periphery of the second plate.
16 . The heat spreader according to claim 1 , wherein a periphery of the second plate is provided with a flange portion protruding toward the first plate, and the flange portion is welded to the first plate.
17 . The heat spreader according to claim 1 , wherein a ratio of an effective space of the enclosed space to the enclosed space is Q, and 0.6≤Q≤0.75.
18 . A battery, comprising: at least one cell; and at least one heat spreader, wherein each of the at least one heat spreader comprises: a first plate configured to fit against at least one side surface of one of the at least one cell; a second plate hermetically connected to the first plate to form an enclosed space, wherein the enclosed space is filled with a liquid medium; and a plurality of protrusions disposed between the first plate and the second plate and dispersedly arranged in the enclosed space, wherein the protrusions comprise a plurality of protrusion groups, each of the protrusion groups comprises ones of the protrusions sequentially arranged at intervals in a first direction, and two parts of the protrusions respectively belonging to two adjacent ones of the protrusion groups are at least partially staggered in a second direction different from the first direction.
19 . The battery according to claim 18 , wherein the at least one cell comprises two cells, and the at least one heat spreader comprises one heat spreader arranged between the two cells; or the at least one cell comprises two cells, and the at least one heat spreader comprises two heat spreaders arranged between the two cells to respectively fit against the two cells; or the at least one cell comprises two cells, the at least one heat spreader comprises two heat spreaders, one of the two heat spreaders is arranged outside the two cells, and another one of the two heat spreaders is arranged between the two cells; or the at least one cell comprises two cells, the at least one heat spreader comprises two heat spreaders, and the two cells are arranged between the two heat spreaders.
20 . A battery pack comprising a battery, the battery comprising at least one heat spreader and at least one cell, each of the at least one heat spreader comprising: a first plate configured to fit against at least one side surface of one of the at least one cell; a second plate hermetically connected to the first plate to form an enclosed space, wherein the enclosed space is filled with a liquid medium; and a plurality of protrusions disposed between the first plate and the second plate and dispersedly arranged in the enclosed space, wherein the protrusions comprise a plurality of protrusion groups, each of the protrusion groups comprises ones of the protrusions sequentially arranged at intervals in a first direction, and two parts of the protrusions respectively belonging to two adjacent ones of the protrusion groups are at least partially staggered in a second direction different from the first direction.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to International Application No. PCT/CN2025/078023, filed on Feb. 19, 2025, and Chinese Patent Application No. 202422709764.X, filed on Nov. 6, 2024. The disclosures of the abovementioned applications are incorporated herein by reference in their entireties. 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