Battery pack
The use of adhesive-bonded iron and aluminum-alloyed plates in a battery pack's heat exchange element addresses the challenge of joining multiple plates, facilitating assembly, enhancing thermal conductivity, and reducing costs while preventing rust and ensuring watertightness.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- AESC JAPAN LTD
- Filing Date
- 2025-01-08
- Publication Date
- 2026-07-21
AI Technical Summary
Existing battery packs face challenges in easily joining multiple overlapping plates that constitute a heat exchange element.
The heat exchange element is composed of multiple plates containing iron as the main component, which are at least partially bonded together using an adhesive, with at least one plate covered in aluminum or aluminum alloy, and a flow path defined between the plates.
This configuration allows for easy assembly of the heat exchange element, enhances thermal conductivity, reduces material cost, and improves rust prevention while maintaining watertightness.
Smart Images
Figure 2026120030000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a battery pack.
Background Art
[0002] In recent years, various battery packs have been developed. A battery pack may include a battery module and a heat exchange element thermally coupled to the battery module.
[0003] Patent Document 1 describes a battery pack. The battery pack includes a battery tray and a water-cooling plate provided at the bottom of the battery tray. The battery tray and the water-cooling plate are steel plates plated with an aluminum alloy. The battery tray and the water-cooling plate are roll-welded to each other.
[0004] Patent Document 2 describes a battery pack. The battery pack includes a cooling plate assembly. The cooling plate assembly has a pan member, a corrugated support member, a cover plate, and a heat conduction layer. The pan member, the corrugated support member, and the cover plate are made of steel. The pan member and the cover plate are welded to each other.
Prior Art Documents
Patent Documents
[0005]
Patent Document 1
Patent Document 2
Summary of the Invention
Problems to be Solved by the Invention
[0006] In battery packs, the heat exchange elements thermally coupled to the battery module may consist of multiple overlapping plates. In such battery packs, there is sometimes a need for a simple way to join these multiple plates together.
[0007] One example of the object of the present invention is to easily join multiple plates that constitute a heat exchange element. Other objects of the present invention will become apparent from the description herein. [Means for solving the problem]
[0008] One aspect of the present invention is as follows: 1. Battery module and, A heat exchange element thermally coupled to the aforementioned battery module, Equipped with, The heat exchange element has multiple plates that overlap each other and contain iron as the main component, A battery pack in which the aforementioned multiple plates are at least partially bonded to each other by adhesive. 2. The heat exchange element defines a flow path between the plurality of plates, The battery pack according to 1, wherein the adhesive is located at least partially around the flow path. 3. The battery pack according to 1. or 2., wherein each of the plurality of plates is covered with at least one of aluminum and aluminum alloy. 4. A battery pack according to any one of 1 to 3, wherein at least one of the plates is formed by cold pressing. [Effects of the Invention]
[0009] According to the above embodiment of the present invention, multiple plates constituting a heat exchange element can be easily joined together. [Brief explanation of the drawing]
[0010] [Figure 1] This is a schematic plan view of a battery pack according to an embodiment. [Figure 2] This is a cross-sectional view AA in Figure 1. [Figure 3] Figure 1 is a cross-sectional view of the lower plate in the BB. [Modes for carrying out the invention]
[0011] Embodiments of the present invention will be described below with reference to the drawings. In all drawings, similar components are denoted by the same reference numerals, and their descriptions are omitted where appropriate.
[0012] Figure 1 is a schematic plan view of the battery pack 10 according to the embodiment. Figure 2 is a cross-sectional view of AA in Figure 1. Figure 3 is a cross-sectional view of the lower plate 310 at BB in Figure 1. For illustrative purposes, the upper plate 330 shown in Figure 2 has been removed in Figure 1.
[0013] In this embodiment, the battery pack 10 is mounted in an automobile. Specifically, the battery pack 10 is mounted between the front and rear wheels of the automobile. Unless otherwise specified, the following description assumes that the battery pack 10 is mounted in an automobile. However, the battery pack 10 can also be applied to applications other than automobiles.
[0014] Each figure shows the X, Y, and Z directions for explanatory purposes. The X direction indicates the front-to-back direction of the battery pack 10. The Y direction is perpendicular to the X direction. The Y direction indicates the left-to-right direction of the battery pack 10. The Z direction is perpendicular to both the X and Y directions. The Z direction indicates the up-to-down direction of the battery pack 10. The arrows pointing to the X, Y, and Z directions indicate the front, left, and up directions of the battery pack 10, respectively. In Figure 1, the white circle with a black dot indicating the Z direction indicates that the arrow pointing to the Z direction extends from the back of the page to the front. In Figure 2, the white circle with a black dot indicating the X direction indicates that the arrow pointing to the X direction extends from the back of the page to the front. In Figure 3, the white circle with a black dot indicating the Y direction indicates that the arrow pointing to the Y direction extends from the back of the page to the front. However, the relationship between the X, Y, and Z directions and the front-to-back, left-to-right, and up-to-down directions of the battery pack 10 is not limited to this example.
[0015] In this embodiment, the front-to-back, left-to-right, and up-to-down directions of the battery pack 10 are determined by the vehicle in which the battery pack 10 is mounted. The X, Y, and Z directions represent the front-to-back, left-to-right, and up-to-down directions of the vehicle, respectively. The arrows pointing to the X, Y, and Z directions represent the front, left, and up directions of the vehicle, respectively. However, the relationship between the front-to-back, left-to-right, and up-to-down directions of the battery pack 10 and the front-to-back, left-to-right, and up-to-down directions of the vehicle is not limited to this example.
[0016] Hereafter, where necessary, the side indicated by the arrow showing the X direction will be referred to as the +X side, and the opposite side of the side indicated by the arrow showing the X direction will be referred to as the -X side. Hereafter, where necessary, the side indicated by the arrow showing the Y direction will be referred to as the +Y side, and the opposite side of the side indicated by the arrow showing the Y direction will be referred to as the -Y side. Hereafter, where necessary, the side indicated by the arrow showing the Z direction will be referred to as the +Z side, and the opposite side of the side indicated by the arrow showing the Z direction will be referred to as the -Z side.
[0017] Referring to FIGS. 1 to 3, the battery pack 10 according to the embodiment will be described.
[0018] As shown in FIG. 1, the battery pack 10 includes a plurality of battery modules 100, a junction box 200, and a pack housing 300.
[0019] In the example shown in FIG. 1, four battery modules 100 are arranged in two rows and two columns in the X direction and the Y direction, respectively. The number and arrangement of the battery modules 100 are not limited to the number and arrangement shown in FIG. 1. For example, the number of battery modules 100 mounted on the battery pack 10 may be only one. Alternatively, the battery pack 10 may include, for example, five or more battery modules 100.
[0020] Each battery module 100 has a plurality of battery cells (not shown) stacked in a direction perpendicular to the Z direction. The plurality of battery cells are electrically connected to each other in series, in parallel, or in a combination of series and parallel. As shown in FIG. 1, each battery module 100 further has a module housing 110 that houses the battery cells (not shown). Each module housing 110 has a substantially rectangular parallelepiped shape. As shown in FIG. 1, when viewed from the Z direction, each module housing 110 has a substantially rectangular shape having a pair of sides substantially parallel to the X direction and a pair of other sides substantially parallel to the Y direction. As shown in FIG. 1, protrusions 112 are provided on both sides in the Y direction of each module housing 110. When viewed from the Z direction, each protrusion 112 extends in the X direction. However, the shape of the protrusion 112 is not limited to the shape shown in FIG. 1.
[0021] As shown in FIG. 1, the junction box 200 is located on the +X side with respect to the two battery modules 100 located on the +X side. The position where the junction box 200 is arranged is not limited to the position shown in FIG. 1. The plurality of battery modules 100 and the junction box 200 are electrically connected by a bus bar (not shown).
[0022] As shown in Figures 1 and 2, the pack housing 300 has a lower plate 310, a side frame 320, an upper plate 330, and a support frame 340. The pack housing 300 houses a plurality of battery modules 100 and a junction box 200. As shown in Figures 2 and 3, the lower plate 310 includes a first lower plate 312 and a second lower plate 314.
[0023] The first lower plate 312 has a substantially plate shape that is substantially perpendicular to the Z direction. The multiple battery modules 100 and junction box 200 are located on the +Z side relative to the +Z side surface of the first lower plate 312. As shown in Figure 1, the first lower plate 312 has a substantially rectangular shape with a pair of long sides substantially parallel to the X direction and a pair of short sides substantially parallel to the Y direction. The shape of the first lower plate 312 is not limited to the example shown in Figure 1.
[0024] The first lower plate 312 and the second lower plate 314 are positioned on the -Z side relative to the first lower plate 312, and overlap each other in the Z direction. As shown in Figures 2 and 3, the second lower plate 314 defines a recess that is partially indented toward the -Z side by the bent portion of the second lower plate 314. The recess defined by the bent portion of the second lower plate 314 partially defines a flow path 316 between the first lower plate 312 and the second lower plate 314.
[0025] As shown in Figure 2, each battery module 100 is positioned on the +Z side relative to the +Z side of the first lower plate 312, with the thermal conductive adhesive 150 positioned between the -Z side of the module housing 110 and the +Z side of the first lower plate 312. The -Z side of the module housing 110 and the +Z side of the first lower plate 312 are physically bonded to each other via the thermal conductive adhesive 150 and are thermally bonded to each other via the thermal conductive adhesive 150. Therefore, the thermal conductive adhesive 150 can improve the thermal conductivity between the battery module 100 and the first lower plate 312. However, as long as the battery module 100 and the lower plate 310 are thermally bonded to each other, the thermal conductive adhesive 150 may not be provided, and the -Z side of the module housing 110 and the +Z side of the first lower plate 312 may be in direct contact with each other.
[0026] The lower plate 310 is a heat exchange element for cooling and heating at least one of the multiple battery modules 100. In this embodiment, a coolant such as water can be flowed through the flow path 316. For example, in the cross-sections shown in Figures 2 and 3, the coolant can flow through the flow path 316 from one direction in the Y direction to the other. Therefore, when the coolant is flowing through the flow path 316, the lower plate 310 can function as a cooler for cooling the battery modules 100. The coolant flowing through the flow path 316 is not limited to a liquid such as water, but may also be a gas. Alternatively, by making the temperature of the fluid flowing through the flow path 316 higher than the temperature of the battery modules 100, the lower plate 310 may function as a heat source for heating the battery modules 100. For example, if the battery pack 10 is placed at a relatively low temperature and the temperature of the battery modules 100 is lower than the temperature suitable for the operation of the battery modules 100, the lower plate 310 can heat the battery modules 100.
[0027] The structure of the lower plate 310 is not limited to the examples shown in Figures 2 and 3. For example, the lower plate 310 may include three or more plates stacked on top of each other in the Z direction. Even when the lower plate 310 includes three or more plates, by flowing an appropriate fluid through a channel defined between the overlapping plates in the Z direction, the lower plate 310 becomes a heat exchange element for cooling and heating at least one of the multiple battery modules 100.
[0028] The side frame 320 extends from the entire circumference of the +Z-side face of the first lower plate 312 in the +Z direction toward the +Z direction. Viewed from the Z direction, the side frame 320 surrounds the area where the multiple battery modules 100 and junction box 200 are located.
[0029] The upper plate 330 is located on the +Z side relative to the multiple battery modules 100, the junction box 200, and the side frame 320. Viewed from the Z direction, the first lower plate 312 and the upper plate 330 have substantially the same shape. The side frame 320 and the portion of the upper plate 330 that overlaps with the side frame 320 in the Z direction are fastened to each other by fasteners such as bolts (not shown). With the side frame 320 and the portion of the upper plate 330 that overlaps with the side frame 320 in the Z direction fastened to each other, the lower plate 310, the side frame 320, and the upper plate 330 form a housing space for accommodating the multiple battery modules 100 and the junction box 200.
[0030] As shown in Figure 1, when viewed from the Z direction, the support frame 340 extends in a frame shape that at least partially surrounds each battery module 100. As shown in Figure 1, when viewed from the Z direction, the support frame 340 includes an extension body 342 located on the +Y side relative to the +Y side battery module 100, an extension body 342 located between the +Y side battery module 100 and the -Y side battery module 100, and an extension body 342 located on the -Y side relative to the -Y side battery module 100. When viewed from the Z direction, each extension body 342 extends in the X direction. As shown in Figure 2, each projection 112 is located on the +Z side relative to the +Z side surface of each extension body 342. Each projection 112 and each extension body 342 are fastened to each other by fasteners such as bolts (not shown). With each projection 112 and each extension body 342 fastened to each other, each battery module 100 and the pack housing 300 are attached to each other.
[0031] The battery pack 10 will be further described with reference to Figures 2 and 3.
[0032] The first lower plate 312 and the second lower plate 314 according to this embodiment contain iron as the main component. Specifically, the first lower plate 312 and the second lower plate 314 are steel plates and are made of steel. By using the first lower plate 312 and the second lower plate 314 which contain iron as the main component, the strength of the lower plate 310 can be made relatively high. Furthermore, by using the first lower plate 312 and the second lower plate 314 which contain iron as the main component, the cost of the lower plate 310 can be reduced compared to the case in which the first lower plate 312 and the second lower plate 314 which contain metals other than iron, such as aluminum, as the main component, the cost of the lower plate 310 can be reduced. Hereinafter, unless otherwise specified, the first lower plate 312 and the second lower plate 314 will be described as steel plates.
[0033] The first lower plate 312 and the second lower plate 314 are plated with at least one of aluminum and aluminum alloy. Therefore, the first lower plate 312 and the second lower plate 314 are covered with at least one of aluminum and aluminum alloy. Thus, the rust prevention of the steel constituting the first lower plate 312 and the second lower plate 314 against refrigerants such as water flowing in the flow path 316 can be improved by the aluminum and aluminum alloy. If there is no possibility of rust occurring on the steel constituting the first lower plate 312 and the second lower plate 314, such as when water does not come into contact with the first lower plate 312 and the second lower plate 314, then the first lower plate 312 and the second lower plate 314 do not need to be covered with either aluminum or aluminum alloy.
[0034] At least one of the first lower plate 312 and the second lower plate 314 may be formed by, for example, a cold press. Compared to a hot press, the first lower plate 312 and the second lower plate 314 can be formed at a lower cost by a cold press. However, the first lower plate 312 and the second lower plate 314 may also be formed by a hot press.
[0035] The -Z side of the first lower plate 312 and the +Z side of the second lower plate 314 are at least partially bonded to each other by the adhesive 400. In the example shown in Figures 2 and 3, the adhesive 400 is at least partially located around the channel 316 between the -Z side of the first lower plate 312 and the +Z side of the second lower plate 314. Thus, the channel 316 can be sealed watertight by the adhesive 400.
[0036] The adhesive 400 is not particularly limited, as long as the -Z side surface of the first lower plate 312 and the +Z side surface of the second lower plate 314 are bonded to each other by the adhesive 400. In one example, the adhesive 400 is at least one of epoxy adhesives, silicone adhesives, acrylic adhesives, and urethane adhesives.
[0037] In this embodiment, compared to the case where the -Z side surface of the first lower plate 312 and the +Z side surface of the second lower plate 314 are joined to each other by CO2 welding, the use of CO2 for welding can be reduced, and deformation of the first lower plate 312 and the second lower plate 314 due to the heat generated by welding can be suppressed. Furthermore, compared to the case where the -Z side surface of the first lower plate 312 and the +Z side surface of the second lower plate 314 are joined to each other by brazing material, the first lower plate 312 and the second lower plate 314 can be joined to each other at a lower cost. Therefore, in this embodiment, the first lower plate 312 and the second lower plate 314 can be joined to each other more easily compared to the case where CO2 welding or brazing material is used. Furthermore, in this embodiment, compared to the case where CO2 welding or brazing material is used, it is easier to ensure the watertightness of the flow path 316.
[0038] The embodiments of the present invention have been described above with reference to the drawings, but these are merely examples of the present invention, and various other configurations can also be adopted.
[0039] In this embodiment, overlapping steel plates are bonded together with an adhesive to form a heat exchange element. This method of bonding overlapping plates together with an adhesive to form a heat exchange element is applicable not only to steel plates but also to plates containing metals other than iron, such as aluminum. For example, multiple overlapping aluminum plates or multiple overlapping aluminum alloy plates may be bonded together with an adhesive to form a heat exchange element. The materials of the multiple plates bonded together with the adhesive do not have to be the same. Multiple plates made of different materials may be bonded together with an adhesive. For example, steel plates and aluminum plates may be bonded together with an adhesive. [Explanation of Symbols]
[0040] 10 Battery pack, 100 Battery module, 110 Module housing, 112 Protrusion, 150 Thermal conductive adhesive, 200 Junction box, 300 Pack housing, 310 Lower plate, 312 First lower plate, 314 Second lower plate, 316 Flow channel, 320 Side frame, 330 Upper plate, 340 Support frame, 342 Extension body, 400 Adhesive
Claims
1. Battery module and A heat exchange element thermally coupled to the aforementioned battery module, Equipped with, The heat exchange element has multiple plates that overlap each other and contain iron as the main component, A battery pack in which the aforementioned multiple plates are at least partially bonded to each other by adhesive.
2. The heat exchange element defines a flow path between the plurality of plates, The battery pack according to claim 1, wherein the adhesive is at least partially located around the flow path.
3. The battery pack according to claim 1 or 2, wherein each of the plurality of plates is covered with at least one of aluminum and an aluminum alloy.
4. The battery pack according to claim 1 or 2, wherein at least one of the plates is formed by cold pressing.