Heat dissipation device, liquid cooling heat dissipation assembly and battery pack

Abstract

The utility model discloses a heat dissipation device, a liquid cooling heat dissipation assembly and a battery pack. The problem of thermal runaway of the battery pack caused by local heat accumulation due to uneven heat dissipation of a battery pack is solved. The heat dissipation device comprises a shell, the shell is provided with a liquid inlet end and a liquid outlet end which deviate from each other in the first direction, and a first side wall and a second side wall which are opposite to each other in the second direction; at least one flow choking structure sunken towards the second direction is arranged between the liquid inlet end and the liquid outlet end, and the at least one flow choking structure is located on the first side wall and / or the second side wall; the shell is internally provided with at least one first flow channel and a plurality of second flow channels, the second flow channels are located on the two sides of the flow blocking structure in the first direction, the second flow channels communicate with the first flow channel, and the second flow channels communicate with the second flow channel in the second direction; the flow choking structure is used for enabling cooling liquid in the multiple upstream second flow channels to converge into the first flow channel and then flow into the multiple downstream second flow channels.

Description

A heat dissipation device, a liquid cooling heat dissipation component, and a battery pack Technical Field

[0001] This application relates to the field of lithium-ion battery heat dissipation technology, and in particular to a heat dissipation device, a liquid cooling heat dissipation component, and a battery pack. Background Technology

[0002] When a battery pack is operating, different areas may experience temperature variations. When using liquid cooling systems to dissipate heat from the battery pack, the coolant within the system will also exhibit temperature differences corresponding to the different temperature zones within the battery pack. If the coolant temperature is higher upstream, it will remain at a higher temperature as it flows downstream, resulting in poor heat dissipation for the battery pack in the downstream areas. Summary of the Invention

[0003] To address the aforementioned issues, this application provides a heat dissipation device, a liquid cooling component, and a battery pack, which reduces the problem of battery pack thermal runaway caused by uneven heat dissipation leading to localized heat accumulation.

[0004] In a first aspect, the heat dissipation device provided in the embodiments of this application includes a housing, the housing having an inlet end and an outlet end that are opposite to each other along a first direction, and a first sidewall and a second sidewall that are opposite each other along a second direction; at least one flow-blocking structure recessed in the second direction is provided between the inlet end and the outlet end, the at least one flow-blocking structure being located on the first sidewall and / or the second sidewall; at least one first flow channel and a plurality of second flow channels are provided inside the housing, the plurality of second flow channels being located on both sides of the flow-blocking structure along the first direction, the plurality of second flow channels being respectively connected to the first flow channel, and the flow-blocking structure being used to allow the coolant in the plurality of second flow channels upstream to flow into the first flow channel and then to flow into the plurality of second flow channels downstream.

[0005] In the above embodiment, the flow-blocking structure can redistribute the heat of the coolant in each of the upstream flow channels to the downstream flow channels, promoting heat exchange between coolants with different temperatures, reducing the temperature difference of the coolant in the downstream flow channels, and thus making the temperature of each downstream flow channel more uniform. Specifically, coolant simultaneously enters the first flow channel and multiple upstream second flow channels from the inlet end. The coolant in the first flow channel flows from the inlet end to the outlet end. When the coolant in the second flow channels flows through the flow-blocking structure, it is blocked by the structure. The coolant in the multiple second flow channels changes its flow direction and enters the first flow channel. At this time, the coolant with uneven temperature in each of the second flow channels mixes and becomes uniformly heated. Then, part of the uniformly heated coolant enters the downstream second flow channel, while the other part flows along the first flow channel to the outlet end. The heat of the coolant is redistributed, so that the temperature of the coolant in the downstream first flow channel and each of the second flow channels is balanced.

[0006] Secondly, embodiments of this application also provide a liquid cooling heat dissipation assembly, including a cold plate and at least one heat dissipation device. The heat dissipation devices are spaced apart from each other along a third direction, wherein the first direction, the second direction, and the third direction are perpendicular to each other, and the cold plate is connected to the at least one heat dissipation device via piping. The liquid cooling heat dissipation assembly has good temperature uniformity and a large heat exchange area, resulting in good heat dissipation performance.

[0007] Thirdly, embodiments of this application also provide a battery pack, including a battery assembly and a liquid cooling heat dissipation component. The battery assembly is installed between the heat dissipation device and the at least one heat dissipation device, and is thermally connected to the heat dissipation device and the heat dissipation device. The liquid cooling heat dissipation component has good temperature uniformity and a large heat exchange area, resulting in good heat dissipation. This enables the battery pack to maintain a better operating temperature, improving the safety of the battery pack. Attached Figure Description

[0008] Figure 1 is a schematic diagram of the heat dissipation device provided in one embodiment of this application;

[0009] Figure 2 is a schematic diagram of the structure of a heat dissipation device provided in another embodiment of this application;

[0010] Figure 3 is a schematic diagram of the structure of a heat dissipation device provided in another embodiment of this application;

[0011] Figure 4 is a schematic diagram of the structure of a heat dissipation device provided in another embodiment of this application;

[0012] Figure 5 is a schematic diagram of the structure of a heat dissipation device provided in another embodiment of this application;

[0013] Figure 6 is a cross-sectional view of the flow channel provided in one embodiment of this application;

[0014] Figure 7 is a cross-sectional view of the flow channel provided in another embodiment of this application;

[0015] Figure 8 is a cross-sectional view of the flow channel provided in another embodiment of this application;

[0016] Figure 9 is a cross-sectional view of the flow channel provided in another embodiment of this application;

[0017] Figure 10 is a structural diagram of a liquid cooling heat dissipation assembly provided in an embodiment of this application;

[0018] Figure 11 is a side view of the battery pack provided in one embodiment of this application;

[0019] Figure 12 is a schematic diagram of the assembly of a heat dissipation device and a battery pack provided in an embodiment of this application;

[0020] Figure 13 is an assembly diagram of the heat dissipation device and battery pack provided in another embodiment of this application;

[0021] Figure 14 is a bottom view of a liquid cooling heat dissipation assembly provided in one embodiment of this application.

[0022] Figure label:

[0023] 1-Shell; 101-Inlet; 102-Outlet; X-First direction; Y-Second direction; Z-Third direction; 103-First sidewall; 104-Second sidewall; 2-Flow-blocking structure; 110-First flow channel; 120-Second flow channel; 130-Third flow channel; 105-Separator plate; 140-Merging flow channel; 201-Bottom wall; 202-Third sidewall; 203-Fourth sidewall; 100-Heat dissipation device; 200-Cold plate; 300-Battery pack; 400-Second cold plate; 500-Structural component; 301-Battery cell; 3011-Terminal post. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description of the application is provided in conjunction with the accompanying drawings and embodiments.

[0025] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to also include expressions such as “one or more” unless the context clearly indicates otherwise.

[0026] References to “an embodiment” or “a specific embodiment” as used in this specification mean that one or more embodiments of this application include a particular feature, structure, or characteristic described in connection with that embodiment. The terms “comprising,” “including,” “having,” and variations thereof mean “including, but not limited to,” unless otherwise specifically emphasized.

[0027] A battery cell is the smallest unit in a battery that provides energy. In related technologies, a battery cell mainly includes a housing and battery cover assembly that enclose a cavity, a cell assembly disposed within the cavity, and electrolyte filling the cavity through an injection hole on the battery cover assembly. The cell assembly mainly includes a positive electrode sheet, a negative electrode sheet, and a separator assembled together in a wound or stacked manner, as well as a Mylar coating film that provides insulation and protection for the cell assembly. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The uncoated positive current collector sheets are stacked together to form the positive electrode tab, which is used for electrical connection to the positive electrode post disposed on the battery cover assembly. The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector. The uncoated negative current collector layers are stacked together to form the negative electrode tab, which is used for electrical connection to the negative electrode post located on the battery cover assembly. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, the positive active material layer can be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc., the negative current collector can be made of copper, and the negative active material layer can be made of carbon or silicon, etc. The separator material can be PP (polypropylene) or PE (polyethylene), etc.

[0028] As a critical node connecting the battery to the external circuit, the terminals bear the entire input / output function of the current. During charging and discharging, the current is highly concentrated at these points, leading to a significant increase in Joule heating. This is especially pronounced under high-rate charging and discharging conditions, further exacerbating the local temperature rise. Furthermore, the contact resistance at the connection between the terminals and the current collector is relatively high. Under high-voltage and high-current conditions, considerable heat accumulation can occur.

[0029] In related technologies, battery packs are composed of multiple battery cells connected in series and / or parallel. Each battery cell generates heat during operation. Due to the close arrangement of multiple battery cells, if one battery cell experiences thermal runaway, heat can easily spread, leading to thermal runaway of the entire battery pack and potentially causing a fire. Therefore, a cooling system is needed to dissipate heat from the battery pack and stabilize its temperature for normal operation. Because different areas of the battery pack have varying temperatures—for example, the area near the tabs and terminals is warmer than other areas—and because the heat dissipation device is thermally connected to the battery pack, temperature differences in the coolant can also occur in different areas of the heat dissipation device. This can lead to uneven heat dissipation within the battery pack, and localized heat buildup may result in thermal runaway.

[0030] In view of this, embodiments of this application provide a heat dissipation device, a liquid cooling component, and a battery pack, reducing the problem of battery pack thermal runaway caused by uneven heat dissipation leading to localized heat accumulation. Embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0031] Figure 1 is a schematic diagram of a heat dissipation device provided in an embodiment of this application. As shown in Figure 1, the heat dissipation device provided in this application includes a housing and a coolant flowing within the housing. The housing has an inlet end 101 and an outlet end 102 that are opposite to each other along a first direction X. The heat dissipation device is filled with coolant, which enters the housing 1 from the inlet end 101 and flows out of the housing 1 from the outlet end 102. The housing 1 also has a first sidewall 103 and a second sidewall 104 that are opposite each other along a second direction Y. Specifically, the heat dissipation device can be a rectangular structure, where the first direction X is the length direction of the heat dissipation device, the second direction Y is the width direction of the heat dissipation device, and the first direction X is perpendicular to the second direction Y. At least one flow-blocking structure 2 is provided between the inlet end 101 and the outlet end 102, recessed towards the inside of the housing 1 along the second direction Y. At least one flow-blocking structure 2 is located on the first sidewall 103 and / or the second sidewall 104. From the outside of the heat dissipation device, the flow-blocking structure 2 appears as a groove on the housing 1.

[0032] The housing 1 contains at least one first flow channel 110 and a plurality of second flow channels 120. Along a first direction X, the plurality of second flow channels 120 are located on both sides of the flow-blocking structure 2, and all of the second flow channels 120 are connected to the first flow channel 110. Along a second direction Y, the first flow channel 110 is located on the sides of the plurality of second flow channels 120 and the flow-blocking structure 2. The flow-blocking structure 2 is used to allow the coolant in the upstream plurality of second flow channels 120 to converge into the first flow channel 110, and then to be distributed to the downstream plurality of second flow channels 120.

[0033] In the above embodiments, the heat dissipation device can be applied to the battery pack to dissipate heat from the battery assembly. Since different areas of the battery pack generate different amounts of heat, it is necessary to achieve temperature uniformity to improve the safety of the battery pack. The heat dissipation device of this application includes a flow-blocking structure 2, which can redistribute the heat of the coolant in each upstream flow channel to the downstream flow channel, promoting heat exchange between coolants at different temperatures, reducing the temperature difference of the downstream coolant, and thus making the temperature of each downstream flow channel more uniform. Specifically, coolant simultaneously enters the first flow channel 110 and multiple upstream second flow channels 120 from the inlet end 101. The coolant in the first flow channel 110 flows from the inlet end 101 to the outlet end 102. The coolant in the second flow channels 120 is blocked by the flow-blocking structure 2, causing the coolant in the multiple second flow channels 120 to change direction and re-enter the first flow channel 110. At this point, the coolant in each of the second flow channels, which has an uneven temperature, mixes and becomes uniformly heated. Then, a portion of the uniformly heated coolant enters the downstream second flow channel 120, while the other portion flows along the first flow channel 110 to the outlet end 102. The heat of the coolant is redistributed, balancing the temperature of the coolant in the downstream first flow channel 110 and each of the second flow channels 120.

[0034] Without the flow-blocking structure 2, both the second flow channel 120 and the first flow channel 110 are connected to the inlet end 101 and the outlet end 102, respectively. Each flow channel is independent, and the coolant temperature in each channel differs, leading to uneven heat dissipation in the downstream heat dissipation area. With the flow-blocking structure 2 installed, the second flow channel 120 is interrupted, and the coolant in the second flow channel 120 flows into the first flow channel 110, redistributing the heat and reducing the temperature difference between the downstream flow channels, thus facilitating heat dissipation in the downstream area of ​​the battery pack.

[0035] In addition, the flow-blocking structure 2 can also serve as a relocation mechanism. For example, it can be installed to avoid structural beams, lifting points, or explosion-proof valve openings in the battery pack structure. It also provides better heat dissipation for the battery pack.

[0036] Figure 2 is a schematic diagram of the heat dissipation device provided in another embodiment of this application. As shown in Figure 2, in one embodiment, the housing 1 may be provided with multiple flow-blocking structures 2 along the first direction X. The coolant can undergo multiple convergence and divergence during its flow, thereby balancing the temperature of the coolant in each downstream channel and improving the heat dissipation effect. In this embodiment, the multiple flow-blocking structures 2 are all located on the same side of the housing 1. In other embodiments, the multiple flow-blocking structures may also be located on both sides of the housing. This application does not impose specific limitations on the number of flow-blocking structures 2 or the spacing between adjacent flow-blocking structures 2; these can be specifically configured according to the structure of the battery pack.

[0037] Figure 3 is a schematic diagram of the heat dissipation device provided in another embodiment of this application. As shown in Figure 3, in one embodiment, the housing 1 is further provided with a plurality of third flow channels 130. The plurality of third flow channels 130 are independent of each other and connected to the liquid inlet 101 and the liquid outlet 102. The flow path of the third flow channels 130 is not provided with a flow obstruction structure 2, so that the flow rate of the coolant is faster and the heat dissipation efficiency is higher. The plurality of third flow channels 130 are also independent of the first flow channel 110 and are not connected. When one side of the first sidewall 103 or the second sidewall 104 is provided with a flow obstruction structure 2, along the second direction Y, the first flow channel 110 is located between the third flow channel 130 and the second flow channel 120.

[0038] Figure 4 is a schematic diagram of the heat dissipation device provided in another embodiment of this application. As shown in Figure 4, in one embodiment, both the first sidewall 103 and the second sidewall 104 are provided with flow-blocking structures 2. Multiple third flow channels 130 can be located in the middle of the housing 1. First flow channels 110 are provided on both sides of the multiple third flow channels 130. A second flow channel 120 is provided between the first flow channel 110 and the first sidewall 103, and a second flow channel 120 is provided between the first flow channel 110 and the second sidewall 104. The third flow channels 130 can be used to dissipate heat in areas with lower temperatures, and the faster flow rate can meet the heat dissipation requirements. The second flow channels 120 and the first flow channels 110 on both sides are used for heat exchange in areas with higher temperatures, resulting in better temperature uniformity. In this embodiment, the flow-blocking structures 2 can be arranged opposite each other along the second direction Y. In other embodiments, as shown in Figure 5, the flow-blocking structures 2 can also be arranged alternately along the second direction Y.

[0039] Please continue referring to Figure 3. In one embodiment, the total width of the housing 1 along the second direction Y is L1. The flow-blocking structure 2 includes a bottom wall 201, which is located on the first side wall 103. The bottom wall 201 and the second side wall 104 are arranged opposite each other along the second direction Y and separated by a preset distance L2. The total width L1 of the housing 1 and the preset distance L2 satisfy: 0.2≤L2 / L1≤0.7. The length units of L2 and L1 are the same. The value of L2 / L1 is within the above design range, which can achieve a better temperature uniformity effect. The value of L2 / L1 can be, for example, 0.2, 0.4, 0.5, 0.6, 0.7, etc., but is not limited to these values. If the flow-blocking structure 2 is recessed too deeply into the housing 1, that is, L2 is too small, it will cause the flow channel width of the first flow channel 110 and the third flow channel 130 in the corresponding area of ​​the flow-blocking structure 2 to be too narrow, increasing the flow resistance at this point and affecting the flow of coolant. If L2 is too large, the effect of coolant converging at the flow obstruction structure 2 will be worse, the coolant will not mix evenly, resulting in poor temperature uniformity of the downstream coolant.

[0040] In another embodiment, the flow-blocking structure 2 can also be disposed on the second sidewall 104. The total width of the housing 1 along the second direction Y is L1. The bottom wall 201 and the first sidewall 103 are disposed opposite each other along the second direction Y and spaced apart by a preset distance L3; the total width L1 of the housing 1 and the preset distance L3 satisfy: 0.2≤L3 / L1≤0.7, and the length measurement units of L3 and L1 are the same. The value of L3 / L1 can be, for example, 0.2, 0.4, 0.5, 0.6, 0.7, etc., but is not limited to these values.

[0041] Please continue referring to Figure 3. In one embodiment, the total length M1 of the housing 1 along the first direction X and the length M2 of the flow-blocking structure 2 satisfy: 0.05 ≤ M2 / M1 ≤ 0.2. The units of measurement for the lengths of M1 and M2 are the same. A ratio of M2 to M1 within the above design range can achieve a better temperature uniformity. The value of M2 / M1 can be, for example, 0.05, 0.07, 0.08, 0.1, 0.15, 0.2, etc., but is not limited to these values. The area corresponding to the first flow channel 110 and the flow-blocking structure 2 is the confluence region. If the value of M2 is too small, the length of the confluence region will be short. The coolant will flow through this area for a short time, resulting in poor temperature uniformity and increased flow resistance in the confluence region. If the value of M2 is too large, the heat dissipation area of ​​the heat dissipation device will be reduced, affecting the heat dissipation effect. It is worth noting that when the housing 1 is provided with a flow-blocking structure 2, M2 is the length of that flow-blocking structure 2. When the housing is provided with multiple flow-blocking structures 2, M2 is the sum of the lengths of the multiple flow-blocking structures 2.

[0042] Referring again to Figure 3, in a further embodiment, the heat dissipation device further includes a plurality of partition plates 105 spaced apart along the second direction Y. The partition plates 105 divide the housing 1 into a first flow channel 110, a second flow channel 120, and a third flow channel 130. The extension direction of the first flow channel 110, the second flow channel 120, and the third flow channel 130 is the first direction X. The flow obstruction structure 2 includes a bottom wall 201, which is located on the first side wall 103. The bottom wall 201 and the second side wall 104 are arranged opposite each other along the second direction Y and spaced apart by a preset distance L2. The total width L1 of the housing 1 and the preset distance L2 satisfy: 0.35≤L2 / L1≤0.7. The length units of L1 and L2 are the same. The value of L2 / L1 can be, for example, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, etc., but is not limited to these values. Because the flow channels are separated by partition plates 105, and partition plates 105 themselves have thickness, they occupy space within the housing 1, reducing the cross-sectional area of ​​the flow channels. Therefore, if the value of L2 is less than the above design range, it will affect the flow resistance of the flow channels.

[0043] In another embodiment, the flow-blocking structure 2 is located on the second sidewall 104, and the bottom wall 201 is disposed opposite to the second sidewall 104 along the second direction Y and spaced apart by a preset distance L3; the total width L1 of the housing 1 and the preset distance L3 satisfy: 0.35≤L3 / L1≤0.7. The length units of L3 and L1 are the same. The value of L3 / L1 can be, for example, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, etc., but is not limited to these values.

[0044] Figures 6-9 show cross-sectional views of several flow channels. As shown in Figures 6-9, in some of the embodiments described above, the cross-section of the flow channel can take the following forms: When the partition plate 105 is arranged parallel to the first sidewall 103 or the second sidewall 104, the cross-section of the flow channel is square. When the partition plate 105 is not parallel to the first sidewall 103 or the second sidewall 104, the cross-section of the flow channel can be triangular or trapezoidal. The partition plate 105 can also be an arc-shaped partition plate 105; multiple partition plates 105 spliced ​​together to form a wave shape result in a flow channel cross-section approximately semi-circular. This application does not impose specific limitations on the cross-sectional shape and size of the flow channel; it can be specifically set according to heat dissipation requirements.

[0045] In one embodiment, since the flow-blocking structure 2 is constantly impacted by the coolant in the second flow channel 120, it needs to meet certain strength requirements. Therefore, when manufacturing the heat dissipation device, the wall thickness of the flow-blocking structure 2 can be made greater than the wall thickness of the shell 1 to improve the strength of the heat dissipation device and thus improve its reliability.

[0046] Because harmonica tubes are relatively inexpensive, they can be processed and used as heat dissipation devices. In one specific processing embodiment, the aforementioned heat dissipation device can be manufactured using a harmonica tube. Specifically, a groove is machined into the first sidewall 103 or the second sidewall 104 of the harmonica tube. Then, a U-shaped sealing element is welded to the groove, serving as the flow obstruction structure 2 of the heat dissipation device.

[0047] The harmonica tube has multiple parallel and spaced-apart partitions 105, which divide the tube into multiple flow channels connecting the inlet end 101 and the outlet end 102. After a groove is machined into the first sidewall 103 or the second sidewall 104 of the harmonica tube, the partition 105 in the grooved area is cut off. The cut partition 105 is referred to as the first partition, and the second flow channel 120 is formed between adjacent first partitions. Since the sealing member has a Z-shaped structure, the first partition and the sealing member are spaced at a predetermined distance along the first direction X, and the gap between the first partition and the sealing member forms a confluence flow channel 140.

[0048] It is worth noting that the grooves in the harmonica tubes are preferably machined using milling, but other processes can also be used to create the grooves.

[0049] In one embodiment, the total cross-sectional area N1 of the plurality of second flow channels 120 and the cross-sectional area N2 of the confluence flow channel 140 satisfy: 0.4 ≤ N2 / N1 ≤ 0.7. N2 and N1 have the same area unit. A value of N2 / N1 within the above design range can achieve a good temperature uniformity effect. The value of N2 / N1 can be, for example, 0.4, 0.5, 0.6, 0.7, etc., but is not limited to these values. If the value of N2 is small, the flow resistance of the confluence flow channel 140 will increase, affecting the flow of the confluenced coolant. If the value of N2 is large, the cross-section of the confluence flow channel 140 will be large, making it difficult for the coolant to mix evenly, resulting in poor heat exchange.

[0050] In one embodiment, the flow-blocking structure 2 includes a bottom wall 201, and a third side wall 202 and a fourth side wall 203 connected to and opposite to the bottom wall 201. A predetermined distance is maintained between the upstream first partition plate and the third side wall 202, forming a confluence channel 140. A predetermined distance is maintained between the downstream first partition plate and the fourth side wall 203, forming a confluence channel. The connection between the third side wall 202 and the bottom wall 201 is rounded, and the connection between the fourth side wall 203 and the bottom wall 201 is also rounded. Rounding the corners ensures smoother flow of liquid through the flow-blocking structure 2.

[0051] Secondly, embodiments of this application also provide a liquid cooling heat dissipation assembly. Figure 10 is a structural diagram of a liquid cooling heat dissipation assembly provided in one embodiment of this application, and Figure 11 is a side view of a battery pack provided in one embodiment of this application. As shown in Figures 10 and 11, the liquid cooling heat dissipation assembly includes a cold plate 200 and at least one heat dissipation device 100 as described in the above embodiments. Along the third direction Z, the cold plate 200 and at least one heat dissipation device 100 are spaced apart to form a receiving space, which can be used to install the battery pack 300. The third direction Z can be considered as the thickness direction of the housing 1, and the first direction X, the second direction Y, and the third direction Z are perpendicular to each other. The cold plate 200 is connected to at least one heat dissipation device 100 by pipes, and the coolant circulates in the cold plate 200 and the heat dissipation device to dissipate heat from the battery pack 300. The cold plate 200 is also provided with flow channels, and the coolant flows in the flow channels to remove the heat from the battery pack 300. The liquid cooling heat dissipation assembly can simultaneously contact two surfaces of the battery pack 300 to dissipate heat from the battery pack 300, and has a large heat exchange area and high heat dissipation efficiency. Furthermore, at least one heat dissipation device has a flow-blocking structure 2, which provides good temperature uniformity.

[0052] Thirdly, embodiments of this application also provide a battery pack. Figure 12 is a schematic diagram of the assembly of a heat dissipation device and a battery pack provided in one embodiment of this application. As shown in Figures 11 and 12, the battery pack includes a battery pack 300 and a liquid cooling heat dissipation component as described in some of the above embodiments. The battery pack 300 is installed between a cold plate 200 and at least one heat dissipation device 100, and is thermally connected to the cold plate 200 and the heat dissipation device 100. The battery pack 300 includes a plurality of battery cells 301, which are arranged along a first direction X to form a battery column. Each battery cell 301 includes a battery cover assembly, two terminals 3011, and a tab (not shown in the figure). The two terminals 3011 are installed in the battery cover assembly, and the tab is disposed inside the battery cell 301 and electrically connected to the terminals 3011. During charging and discharging, the battery cell 301 generates a large amount of heat in the terminal 3011 and tab areas. Therefore, the aforementioned heat dissipation device 100 can be disposed on the side of the battery pack with the battery cover assembly, and located between the two terminals (positive terminal and negative terminal) of the same battery cell 301, while the cold plate 200 is disposed on the side of the battery pack away from the battery cover assembly. In the heat dissipation device 100, the temperature of the coolant in the flow channels near the first side wall 103 and the second side wall 104 is higher, while the temperature of the coolant in the middle flow channel is lower. When the coolant encounters the flow obstruction structure 2, it can be redistributed to achieve a uniform temperature effect. The number of flow obstruction structures 2 can be set according to the length of the battery pack. For example, the number of flow obstruction structures 2 can be proportional to the length of the battery pack; the longer the battery pack, the more flow obstruction structures 2 are required, which allows the coolant to undergo multiple convergence and divergence, resulting in a better uniform temperature effect. For example, Figure 13 is an assembly diagram of a heat dissipation device and a battery pack provided in another embodiment of this application. As shown in Figure 13, the flow obstruction structure 2 can also be set according to the setting position of structural components 500 such as suspension points and structural beams in the battery pack, so as to avoid the suspension points, structural beams and other structural components 500.

[0053] Figure 14 is a bottom view of a liquid cooling heat dissipation assembly provided in one embodiment of this application. As shown in Figure 14, in one embodiment, the battery pack may include a battery group 300 composed of multiple battery columns arranged along a second direction Y. Correspondingly, the battery pack may include multiple heat dissipation devices 100 spaced apart along the second direction Y, each heat dissipation device 100 being thermally connected to one battery column. The multiple heat dissipation devices 100 can be arranged in parallel or in series via a combiner, so that the coolant can circulate among the heat dissipation devices 100 to achieve the effect of heat exchange with the battery group 300.

[0054] In one specific embodiment, the battery pack includes a battery group 300 consisting of a battery column, a heat dissipation device 100, and a cold plate 200. In other words, the battery pack contains a column of battery cells. The heat dissipation device 100 is installed on the side of the column of battery cells with a battery cover assembly, and is located between the positive and negative terminals. The cold plate 200 is installed on the side of the column of battery cells away from the battery cover assembly. A flow-blocking structure 2 is provided on the first sidewall 103. Due to the large amount of heat generated near the terminal area, the coolant in the flow channel near the first sidewall 103 or the second sidewall 104 of the cold plate 200 has a high heat. As the coolant flows from the inlet end 101 (upstream) to the outlet end 102 (downstream), when it flows through the flow-blocking structure 2, the coolant in the second flow channel 120 near the inlet end 101 flows into the first flow channel 110 through the confluence channel, and part of the coolant is then diverted to the second flow channel 120 near the outlet end 102. This ensures that the coolant in the upstream second flow channel 120 is kept at a uniform temperature, reducing the problem of high temperature near the electrode post area, which has low heat dissipation efficiency and is prone to thermal runaway. The battery pack also includes a frame, which has a structural component 500 disposed in the groove formed by the flow-blocking structure 2.

[0055] In another specific embodiment, the battery pack includes a battery group 300 consisting of a battery column, a heat dissipation device 100, and a cold plate 200. In other words, the battery pack contains a column of battery cells. The heat dissipation device 100 is installed on the side of the column of battery cells with the battery cover assembly, and is located between the positive and negative terminals. The cold plate 200 is installed on the side of the column of battery cells away from the battery cover assembly. A flow-blocking structure 2 is provided on the first sidewall 103, and a flow-blocking structure 2 is also provided on the second sidewall 104. Because the heat generation near the terminal post area is relatively high, the coolant in the flow channels near the first sidewall 103 and the second sidewall 104 of the cold plate 200 is also hot. As the coolant flows from the inlet end 101 (upstream) to the outlet end 102 (downstream), when passing through the flow-blocking structure 2, the coolant in the second flow channel 120 near the inlet end 101 flows into the first flow channel 110 via the confluence channel, and some coolant is then diverted to the second flow channel 120 near the outlet end 102. This homogenizes the temperature of the coolant in the upstream second flow channel 120, reducing the problem of high temperature near the terminal post area, which reduces heat dissipation efficiency and is prone to thermal runaway. The battery pack also includes a frame with two structural members 500, each of which is disposed in a groove formed by the flow-blocking structure 2.

[0056] Referring again to Figure 14, in one embodiment, the battery pack includes a battery group 300 consisting of four battery columns, two heat dissipation devices 100, a cold plate 200, and two second cold plates 400, which are harmonica-tube type cold plates. The second cold plates 400 and the heat dissipation devices 100 are spaced apart along a second direction Y. The second cold plates 400 are thermally connected to one battery column, and the heat dissipation devices 100 are thermally connected to the other battery column. The cold plates 200 are located on the side of the battery column opposite to the heat dissipation devices 100 and the second cold plates 400, and are thermally connected to both battery columns. The second cold plates 400 have multiple fourth flow channels (not shown in the figure) arranged in parallel along the second direction Y. The second cold plates 400, the heat dissipation devices 100, and the cold plates 200 are interconnected, and the second cold plates 400 and the heat dissipation devices 100 are arranged in parallel. When the heat generation of the battery column is low, the second cold plates 400 can meet the heat dissipation requirements of the battery column.

[0057] In other embodiments, the battery pack may further include a battery group 300 consisting of two battery columns, a heat dissipation device 100, a second cold plate 400, and a cold plate 200. The heat dissipation device 100 is thermally connected to one battery column, the second cold plate 400 is thermally connected to one battery column, and the cold plate 200 is thermally connected to both battery columns. The number and arrangement of the heat dissipation device 100 and the second cold plate 400 can be specifically configured according to heat dissipation requirements and the position of the structural components 500 within the battery pack; this application does not impose specific limitations.

[0058] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A heat dissipation device, characterized in that, The device includes a housing having an inlet end and an outlet end that are opposite to each other along a first direction, and a first sidewall and a second sidewall that are opposite each other along a second direction. At least one flow-blocking structure recessed in the second direction is provided between the inlet end and the outlet end, and the at least one flow-blocking structure is located on the first sidewall and / or the second sidewall. The housing has at least one first flow channel and a plurality of second flow channels. Along the first direction, the plurality of second flow channels are located on both sides of the flow-blocking structure, and the plurality of second flow channels are respectively connected to the first flow channel. The flow-blocking structure is used to allow the coolant in the plurality of second flow channels upstream to flow into the first flow channel and then to flow into the plurality of second flow channels downstream.

2. The heat dissipation device according to claim 1, characterized in that, The total width of the housing along the second direction is L1; the flow-blocking structure includes a bottom wall, the flow-blocking structure is located on the first side wall, the bottom wall and the second side wall are arranged opposite to each other along the second direction and are spaced apart by a preset distance L2; the total width L1 of the housing and the preset distance L2 satisfy: 0.2≤L2 / L1≤0.

7.

3. The heat dissipation device according to claim 1, characterized in that, Along the first direction, the total length M1 of the shell and the total length M2 of the flow-blocking structure satisfy: 0.05≤M2 / M1≤0.

2.

4. The heat dissipation device according to claim 1, characterized in that, The heat dissipation device further includes a plurality of partition plates spaced apart along the second direction. The partition plates divide the housing into the first flow channel and a plurality of second flow channels. The flow obstruction structure includes a bottom wall. The flow obstruction structure is located on the first side wall. The bottom wall and the second side wall are arranged opposite to each other along the second direction and spaced apart by a preset distance L2. The total width L1 of the housing and the preset distance L2 satisfy: 0.35≤L2 / L1≤0.

7.

5. The heat dissipation device according to claim 1, characterized in that, The wall thickness of the flow-blocking structure is greater than the wall thickness of the shell.

6. The heat dissipation device according to claim 1, characterized in that, The heat dissipation device is made of a harmonica tube with a slot. The flow obstruction structure is a sealing component installed in the slot. The sealing component has a Z-shaped structure.

7. The heat dissipation device according to claim 6, characterized in that, The harmonica tube includes a plurality of parallel and spaced first partition plates, with a second flow channel formed between adjacent first partition plates. Along the first direction, the first partition plates are spaced at a preset distance from the flow-blocking structure, and the gap between the first partition plates and the flow-blocking structure forms a converging flow channel.

8. The heat dissipation device according to claim 7, characterized in that, The sum of the cross-sectional areas N1 of the plurality of second channels and the cross-sectional area N2 of the confluence channel satisfy the following condition: 0.4≤N2 / N1≤0.

7.

9. The heat dissipation device according to claim 6, characterized in that, The flow-blocking structure includes a bottom wall, and a third side wall and a fourth side wall connected to and opposite to the bottom wall. The connection between the third side wall and the bottom wall is rounded, and the connection between the fourth side wall and the bottom wall is also rounded.

10. A liquid-cooled heat dissipation component, characterized in that, It includes a cold plate and at least one heat dissipation device as described in any one of claims 1 to 9, wherein the heat dissipation device is spaced apart from the at least one heat dissipation device along a third direction, the first direction, the second direction and the third direction are perpendicular to each other, and the cold plate and the at least one heat dissipation device are connected by a pipeline.

11. A battery pack, characterized in that, It includes a battery pack and a liquid cooling heat dissipation assembly as described in claim 10, wherein the battery pack is installed between the heat dissipation device and the at least one heat dissipation device, and is thermally connected to the heat dissipation device and the heat dissipation device.

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