Battery pack shell with improved heat dissipation structure

Abstract

The disclosed invention relates to a battery pack case having a space for accommodating at least one battery module. According to one embodiment, a plurality of engraved structures are formed on an upper surface of a substrate, the plurality of engraved structures contact and support a bottom of a battery module, and the plurality of engraved structures form a space for accommodating a thermal resin.

Description

Technical Field

[0001] The present invention relates to a battery pack housing that improves heat dissipation performance of a battery pack by promoting conductive heat transfer from a battery module to the battery pack housing.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0026639, filed on February 28, 2023, the entire contents of which are incorporated herein by reference. Background Art

[0003] Unlike primary batteries, secondary batteries are rechargeable and have been extensively researched and developed in recent years due to their potential for miniaturization and large capacity. The demand for secondary batteries as energy sources is rapidly increasing due to technological development and increased demand for mobile devices, as well as the emergence of electric vehicles and energy storage systems in response to environmental protection needs.

[0004] Secondary batteries are classified into coin-type batteries, cylindrical batteries, square batteries, and pouch-type batteries according to the shape of the battery case. In the secondary battery, an electrode assembly mounted inside the battery case is a chargeable and dischargeable power generation device including a stacked structure of electrodes and separators.

[0005] Since secondary batteries need to be used continuously for a long time, it is necessary to effectively control the heat generated during the charging and discharging process. If the secondary battery is not properly cooled, the increase in temperature will cause an increase in current, which will again cause an increase in temperature, which will cause a chain reaction and eventually lead to a catastrophic condition of thermal runaway.

[0006] In addition, if the secondary batteries are grouped in the form of modules or battery packs, the thermal runaway caused by one secondary battery will cause other secondary batteries nearby to continue to overheat, resulting in a heat propagation phenomenon. In other words, when a battery module in a battery pack experiences thermal runaway, a large amount of conductive dust, gas, and flame are released from the high-voltage terminals of the battery module, which causes dust to accumulate on the high-voltage terminals of other adjacent battery modules and triggers the heat propagation phenomenon through heat transfer from gas and flame.

[0007] A design for preventing or delaying heat transfer from a battery cell or module that has experienced thermal runaway to an adjacent battery cell or module, comprising: a thermal insulation design that uses insulating materials to prevent or delay heat transfer from a battery module that has experienced thermal runaway to an adjacent battery module, and a heat dissipation design that initially and quickly dissipates heat from the battery module that has experienced thermal runaway to the outside of the battery pack to reduce heat transfer to adjacent battery modules.

[0008] Thermal runaway prevention and delay is a critical issue, especially in electric vehicles, where it can lead to life-threatening accidents, and legal regulations are becoming increasingly stringent. In other words, they require a sufficient delay time before the thermal runaway phenomenon spreads to allow time for emergency evacuation and safety measures. Therefore, more effective measures are needed to suppress or delay the occurrence of heat transfer in battery packs. Summary of the invention

[0009] Technical issues

[0010] The present invention is directed to a battery module in which heat generated by a battery module that has generated thermal runaway can be quickly transferred to a battery pack housing in the form of conductive heat transfer, thereby being quickly released to the outside as convection heat transfer in the battery pack housing.

[0011] However, the technical problems to be solved by the present invention are not limited to the above problems, and those skilled in the art can clearly understand other problems not mentioned from the following description of the present invention.

[0012] Technical Solution

[0013] The present invention relates to a battery pack housing, which includes: a space for accommodating at least one battery module, wherein a plurality of engraved structures are formed on an upper surface of a substrate and contact a lower surface supporting the battery module, and the plurality of engraved structures form a space for accommodating a thermal resin.

[0014] In one embodiment of the present invention, the engraved structures form a grid structure that is uniformly arranged longitudinally relative to the upper surface of the substrate.

[0015] The carved structures increase the heat transfer area of ​​the battery module with respect to the thermal resin to be filled in the carved structures, compared with a flat surface.

[0016] In an exemplary embodiment, the engraved structure may form a curved surface including a hemispherical surface and a semi-elliptical surface.

[0017] Alternatively, the engraved structure may form a honeycomb structure.

[0018] At the same time, the present invention provides a battery pack, which includes: a battery module including a plurality of battery cells and a module shell accommodating the plurality of battery cells; a battery pack shell having the above-mentioned configuration; and a thermal resin coated between a lower frame of the battery module and a substrate of the battery pack shell, wherein the thermal resin is filled in a plurality of carved structures formed on the upper surface of the substrate.

[0019] In the battery pack of the present invention, by the thermal resin filled in the engraved structure, a conductive heat transfer area of ​​the substrate with respect to the lower frame of the battery module is increased compared to a flat contact surface.

[0020] Furthermore, the battery pack of the present invention may include a battery pack case, wherein the battery pack case includes a partition wall member partitioning the plurality of battery modules from one another, and the substrate includes a groove formed through a region in contact with the partition wall member.

[0021] In one embodiment, the groove may preferably not be exposed to the outside of the partition wall member.

[0022] Additionally, the grooves may be spaced apart in a plurality of grooves along the partition wall member.

[0023] Beneficial Effects

[0024] The battery pack housing of the present invention has a configuration as described above, wherein a carved structure formed on the top surface of the substrate provides an enlarged heat transfer area for the thermal resin, and the enlarged heat dissipation area provided by the carved structure increases the amount of heat conducted from the battery module to the substrate, thereby allowing the heat of the battery module that has experienced thermal runaway to be quickly transferred to the substrate and dissipated to the outside of the battery pack, thereby helping to suppress or delay heat propagation.

[0025] Furthermore, the grooves formed through the substrate along the partition wall members forming the boundaries between the battery modules physically eliminate a portion of the heat conduction path between the battery modules, thereby reducing and delaying excessive heat transfer caused by the battery module in which thermal runaway occurs, while also further improving heat dissipation in the substrate.

[0026] However, the technical effects that can be obtained by the present invention are not limited to the above-mentioned effects, and those skilled in the art can clearly understand other effects that are not mentioned from the description of the present invention described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Since the following drawings attached to the present specification illustrate exemplary embodiments of the present invention and are used to facilitate understanding of the technical idea of ​​the present invention together with the detailed description of the present invention described below, the present invention should not be limited to be interpreted based on the drawings.

[0028] Figure 1 is a diagram showing a battery pack case according to the present invention.

[0029] Figure 2 is along Figure 1 A cross-sectional view of the cut along the “AA” line.

[0030] Figure 3It is a diagram showing another embodiment of the engraved structure provided on the substrate.

[0031] Figure 4 is a diagram showing a battery pack according to the present invention.

[0032] Figure 5 is a cross-sectional view showing a contact surface of a battery module and a substrate.

[0033] Figure 6 It is shown Figure 5 Diagram of the conductive heat transfer path in a battery pack.

[0034] Figure 7 It is a diagram showing another embodiment of the battery pack case.

[0035] Figure 8 It is shown Figure 7 Diagram of the conductive heat transfer path in a battery pack. DETAILED DESCRIPTION

[0036] The present invention can have various modifications and various embodiments, so specific embodiments thereof will be described in detail below.

[0037] However, it should be understood that the present invention is not limited to the specific embodiments, but includes all modifications, equivalents or alternatives within the spirit and technical scope of the present invention.

[0038] The terms "include", "including" and "having" used herein indicate the presence of the features, numbers, steps, actions, parts or components described herein, or a combination thereof, and it should be understood that they do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, actions, parts, components, or a combination thereof.

[0039] Furthermore, in the present invention, when a part of a layer, film, region, plate, etc. is disposed on another part, this includes not only a case where one part is disposed "directly" on another part, but also a case where another part is interposed therebetween. Conversely, when a part of a layer, film, region, plate, etc. is disposed "below" another part, this includes not only a case where one part is disposed "directly" below another part, but also a case where another part is interposed therebetween. Furthermore, in the present application, "on" may include not only a case where it is disposed on an upper part, but also a case where it is disposed on a lower part.

[0040] The present invention relates to a battery pack case having a space for accommodating at least one battery module. In one example, a plurality of engraved structures are formed on an upper surface of a substrate supported in contact with a lower surface of the battery module, wherein the plurality of engraved structures form a space for accommodating a thermal resin.

[0041] Here, the engraved structure increases the heat transfer area of ​​the battery module with respect to the thermal resin to be filled therein, compared with a flat surface.

[0042] Therefore, from the perspective of heat dissipation design, the battery pack housing of the present invention can quickly transfer the heat generated in the battery module that causes thermal runaway to the battery pack housing in the form of conductive heat transfer by increasing the heat transfer area used for the thermal resin. As a result, a large amount of heat is transferred to the battery pack housing at an early stage, and the heat released to the outside as the convection heat transfer increases, effectively suppressing or delaying the heat propagation within the battery pack.

[0043] Mode for the Invention

[0044] Hereinafter, a specific embodiment of the battery pack housing 100 of the present invention will be described in detail with reference to the accompanying drawings. For reference, the front, rear, up, down, left and right directions used to designate relative positions in the following description are for the purpose of understanding the present invention and refer to the directions shown in the accompanying drawings unless otherwise specified.

[0045] [First embodiment]

[0046] Figure 1 is a diagram showing a battery pack case according to the present invention, and Figure 2 is along Figure 1 A cross-sectional view of the cut along the “AA” line.

[0047] Reference Figure 1 and Figure 2 The battery pack housing 100 shown in FIG. 1 includes a base plate 110 forming a lower surface, a side plate 120 surrounding the periphery of the base plate 110, a partition wall member 130 arranged longitudinally and / or transversely to divide the accommodation space defined by the side plate 120, and a cover 160 closing the upper surface of the accommodation space. In addition, the base plate 110 is provided with a cooling channel 114 through which a cooling fluid is stored or flows. However, although the base plate 110 is Figure 2 1 is shown as being provided with the cooling channel 114 , but a separate cooling plate (not shown) may be coupled to the base plate 110 .

[0048] Reference Figure 1 and Figure 2 The upper surface of the substrate 110 shown in FIG. 1 has a plurality of engraved structures 112 formed in each region contacting the lower surface of the corresponding battery module 200. The plurality of engraved structures 112 may form a grid structure uniformly arranged longitudinally relative to the upper surface of the substrate 110, and the independent engraved structures 112 form an inwardly recessed space.

[0049] The plurality of engraved structures 112 may be manufactured by applying any known processing technology, such as pressing, mechanical cutting, plasma processing, electrolytic processing, etching, casting, etc. In addition, through the plurality of engraved structures 112, the engraved structures may protrude into the interior of the substrate 110 accordingly, but since this may adversely affect the flow of the cooling fluid flowing through the cooling channel 114, it may be desirable that the inner surface of the substrate 110 forming a portion of the cooling channel 114 has a flat surface.

[0050] In the present invention, a plurality of engraved structures 112 formed on the upper surface of the substrate 110 form a space for accommodating the thermal resin 300. A plurality of battery modules 200 are stored in the battery pack case 100 to complete the battery pack 10, wherein the substrate 110 forming the bottom surface of the battery pack case 100 and the lower frame 222 of the module case 220 contact each other to promote conductive heat transfer. In addition, in order to promote conductive heat transfer, the contact surface of the substrate 110 and the module case 220 is interposed with the thermal resin 300 having excellent thermal conductivity.

[0051] When thermal runaway occurs in any battery module 200 within the battery pack 10, a large amount of heat is propagated to the adjacent battery module 200 along the substrate 110 where conductive heat transfer actively occurs. Meanwhile, the substrate 110 is generally provided with a heat dissipation device, such as a cooling channel 114. Therefore, before the heat of the battery module 200 in thermal runaway is diffused to the side outside the substrate 110 by convection heat transfer, it is advantageous to suppress or delay heat propagation by increasing the amount of heat dissipated to the outside of the battery pack 10 by conducting the heat of the battery module 200 within the battery pack housing 100 to the substrate 110 as early as possible.

[0052] From the perspective of heat dissipation, the plurality of engraved structures 112 on the top surface of the substrate 110 provide an expanded heat transfer area for the thermal resin 300 . Figure 2 It is through along Figure 1 ”AA” line cutout, and as shown, the thermal resin 300 filled in the recessed carved structure 112 has an effect of increasing the heat transfer area from the battery module 200 to the substrate 110 compared to a flat contact surface.

[0053] The amount of heat conducted from the battery module 200 to the substrate 110 is proportionally increased through the heat transfer area enlarged by the engraved structures 112, thereby allowing the heat of the battery module 200 that has generated thermal runaway to be transferred to the substrate 110 as quickly as possible and have a chance to dissipate to the outside of the battery pack 10. Therefore, the plurality of engraved structures 112 formed on the upper surface of the substrate 110 helps to suppress or delay the heat propagation mediated by the thermal resin 300.

[0054] exist Figure 2In the exemplary embodiment of the present invention, the engraved structure 112 has a curved surface including a hemispherical surface and a semi-elliptical surface. This is in consideration of the fact that the curved surface is a favorable surface shape for expanding the heat transfer area. Alternatively, as Figure 3 As shown, the engraved structure 112 can form a honeycomb structure. Although the honeycomb structure may be slightly lower than the Figure 2 , but it can effectively compensate for or enhance the supporting stiffness of the substrate 110 , which may be weakened due to the engraved structure 112 .

[0055] [Second embodiment]

[0056] Figure 4 1 is a diagram showing a battery pack 10 according to the present invention. Figure 4 A single battery module 200 is shown in FIG. 1 , but one battery module 200 exists for each independent accommodation space partitioned by the partition wall member 130 .

[0057] The battery module 200 includes a plurality of battery cells 210 and a module housing 220 accommodating the plurality of battery cells 210. In addition, the battery module 200 may further include components such as an insulating material for insulation between the battery cells 210, a bus frame assembly (BFA) for electrical connection and external output between the plurality of battery cells 210, etc., but since these components are not directly related to the heat dissipation design of the battery pack housing 100 according to the present invention, description thereof will be omitted.

[0058] The battery pack case 100 shown includes a base plate 110 forming a lower surface, a side plate 120 surrounding the periphery of the base plate 110, a partition wall member 130 provided longitudinally and / or transversely to divide the accommodation space defined by the side plate 120, and a cover 160 closing the upper surface of the accommodation space. In addition, the base plate 110 is provided with a cooling channel 114 in which a cooling fluid is stored or flows. However, although the cooling channel 114 is Figure 2 and Figure 5 Although shown as being disposed in the base plate 110 , the cooling channel 114 may be organized into a structure in which a separate cooling plate (not shown) is coupled to the base plate 110 .

[0059] Here, the partition wall members 130 can be further distinguished by a longitudinal center beam 140 and transverse cross beams 150, wherein the longitudinal center beam 140 crosses the center of the battery pack housing 100 and divides the internal containing space from one side to the other, and the transverse cross beams 150 cross relative to the center beam 140 to form a grid, depending on their setting direction relative to the substrate 110.

[0060] Figure 5 is a cross-sectional view showing a contact surface of the battery module 200 and the substrate 110 . Figure 5 The battery pack 10 includes the thermal resin 300 applied between the lower frame 222 of the battery module 200 and the substrate 110 of the pack case 100. Therefore, all the engraved structures 112 on the top surface of the substrate 100 are filled with the thermal resin 300.

[0061] As described in the first embodiment, the engraved structure 112 provided on the substrate 110 provides an enlarged heat transfer area for the thermal resin 300 , and the amount of heat conducted from the battery module 200 to the substrate 110 increases proportionally by the enlargement of the heat transfer area achieved on the substrate 110 . Figure 6 It is shown Figure 5 FIG. 1 is a diagram of a conductive heat transfer path in a battery pack 10. Assuming that the depicted battery module 200 is subjected to thermal runaway, since the heat transfer area is increased due to the engraved structure 112, a large amount of heat generated by the thermal runaway is transferred to the substrate 110 in the form of conductive heat transfer. A large amount of heat transferred to the substrate 110 is dissipated through the substrate 110 and discharged from the battery pack 10 by the cooling fluid, thereby reducing the amount of heat conducted to other nearby battery modules 200 using the substrate 110 as a heat conduction medium. This improvement in heat dissipation helps to suppress and delay heat propagation within the battery pack 10.

[0062] Figure 7 is a diagram showing an alternative embodiment of the battery pack case 100. Figure 7 In the illustrated embodiment of the battery pack housing 100, the battery pack housing 100 includes a partition wall member 130 that divides a plurality of battery modules 200 from each other, and at the same time, the substrate 110 includes a through-formed groove 116 in a region in contact with the partition wall member 130. The through-formed groove 116 in the substrate 110 is intended to limit conductive heat transfer across the lower side of the partition wall member 130.

[0063] The partition wall members 130 forming the center beam 140 and / or the cross beam 150 form the boundary between the battery modules 200, and the conductive heat transfer across the partition wall members 130 to the adjacent battery modules 200 is limited by the grooves 116 formed through the base plate 110. In other words, Figure 8 As shown, a portion of the heat conduction path between the battery modules 200 through the substrate 110 is physically eliminated by the groove 116 passing through the substrate 110, thereby reducing and delaying excessive heat transfer due to thermal runaway of the battery module 200. For reference, when the substrate 110 is provided with a cooling channel 114, the groove 116 structure needs to be formed by avoiding the cooling channel 114.

[0064] On the other hand, the through slots 116 in the substrate 110 are also used to enhance heat dissipation by convective heat transfer. In other words, the conductive heat transfer that propagates across the partition wall member 130 to the adjacent battery module 200 is limited and delayed by the through slots 116 formed in the substrate 110, thereby allowing more opportunities for heat dissipation from the substrate 110.

[0065] In one embodiment, it may be desirable that the groove 116 disposed side by side with respect to the partition wall member 130 does not extend beyond the partition wall member 130. To further limit conductive heat transfer, the groove 116 is formed through the substrate 110, which affects the sealing of the battery pack housing 100. Therefore, the tightness of the battery pack housing 100 can be achieved by designing the size of the groove 116 so that the partition wall member 130 completely surrounds the groove 116, so that the partition wall member 130 closes the groove 116 formed through the substrate 110.

[0066] Furthermore, the slots 116 may be spaced apart along the partition wall member 130. Conductive heat transfer occurs in the areas between the spaced apart slots 116, and the plurality of slots 116 being spaced apart, preferably evenly spaced apart, may be advantageous in preventing heat conducted to adjacent battery modules 200 from being locally concentrated and causing another thermal runaway.

[0067] As described above, the present invention has been described in more detail through the drawings and embodiments. However, since the configuration described in the drawings or the configuration described in the embodiments described herein is only one embodiment of the present invention and does not represent the overall technical spirit of the present invention, it should be understood that the present invention covers various equivalent schemes, modifications and substitutions at the time of filing this application.

[0068] [Description of Reference Signs]

[0069] 10: Battery Pack

[0070] 100: Battery pack housing

[0071] 110: Substrate

[0072] 112: Carving structure

[0073] 114: Cooling channel

[0074] 116: Slot

[0075] 120: Side panels

[0076] 130: Partition wall component

[0077] 140: Center beam

[0078] 150: beam

[0079] 160: Cover

[0080] 200: Battery module

[0081] 210: Battery Cell

[0082] 220: Module housing

[0083] 222: Lower frame

[0084] 300: Thermal resin

Claims

1. A battery pack housing, comprising: space for accommodating at least one battery module, A plurality of engraved structures are formed on an upper surface of the substrate and contact and support a lower surface of the battery module, and the plurality of engraved structures form a space for accommodating a thermal resin.

2. The battery pack housing according to claim 1, wherein: The engraved structures form a grid structure that is uniformly arranged longitudinally relative to the upper surface of the substrate.

3. The battery pack housing according to claim 1, wherein: The carved structures increase the heat transfer area of ​​the battery module for the thermal resin to be filled in the carved structures, compared to a flat surface.

4. The battery pack housing according to claim 1, wherein: The engraved structure forms a curved surface including a hemispherical surface and a semi-elliptical surface.

5. The battery pack housing according to claim 2, wherein: The engraved structure forms a honeycomb structure.

6. A battery pack, comprising: A battery module comprising a plurality of battery cells and a module housing accommodating the plurality of battery cells ； The battery pack housing according to any one of claims 1 to 5; and the thermal resin, the thermal resin being applied between the lower frame of the battery module and the substrate of the battery pack case, The thermal resin is filled in the plurality of engraved structures formed on the upper surface of the substrate.

7. The battery pack according to claim 6, wherein: By the thermal resin filled in the engraved structure, a conductive heat transfer area of ​​the substrate with respect to the lower frame of the battery module increases compared to a flat contact surface.

8. The battery pack according to claim 6, wherein: The battery pack case includes a partition wall member that divides the plurality of battery modules from each other. And the substrate includes a groove formed through a region in contact with the partition wall member.

9. The battery pack according to claim 8, wherein: The groove is not exposed to the outside of the partition wall member.

10. The battery pack according to claim 8, wherein: The grooves are spaced apart in a plurality of grooves along the partition wall member.

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