Liquid cooling plate, liquid cooling plate design method and power battery

Abstract

This application relates to the field of battery technology, and in particular to a liquid cooling plate, a liquid cooling plate design method, and a power battery. The liquid cooling plate includes: a main body, which is elongated and includes a cooling surface for contacting a battery cell; and a reinforcing connector. A flow cavity is formed inside the main body, and the reinforcing connector is disposed within the flow cavity. The reinforcing connector is connected to the surface of the cooling surface facing the inside of the flow cavity. The reinforcing connector divides the flow cavity into at least two chambers. The liquid cooling plate provided in this application, through structural optimization design and the addition of a reinforcing connector within the main body, can increase support for the cooling surface on the opposite side of the battery cell, reduce the stress deformation of the main body caused by the expansion of the battery cell, and reduce the risk of leakage due to long-term fatigue of the main body, thereby extending the service life of the liquid cooling plate.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a liquid cooling plate, a liquid cooling plate design method, and a power battery. Background Technology

[0002] Currently, with the rapid development of new energy vehicles, users' demands for the user experience and driving safety of new energy vehicles are becoming increasingly prominent. Regarding the user experience, the long charging time of new energy vehicles has always been a major complaint. To address this, new energy vehicle manufacturers have invested heavily in R&D to improve the fast charging time of power battery systems. In terms of driving safety, to ensure the personal safety of users during vehicle use, various automakers are researching solutions to achieve heat dissipation-free safety in power battery systems. Improving the fast charging time of power battery systems will increase the requirements for system cooling capacity. On the other hand, to achieve the safety goal of heat dissipation-free power battery systems, it is required to quickly remove the heat from the runaway battery cell after it malfunctions. Therefore, both aspects place stringent requirements on the system's cooling capacity.

[0003] Most current cooling solutions utilize bottom-mounted cooling for individual battery cells, which, due to limited heat dissipation area, cannot achieve significant heat dissipation capacity. To improve heat dissipation area, some manufacturers have adopted vertical cooling solutions for individual battery cells. Vertical cooling solutions are divided into two categories: single-vertical cooling and dual-vertical cooling. Single-vertical cooling offers a larger heat dissipation area compared to bottom-mounted cooling, but its heat dissipation capacity still cannot meet the requirements for ultra-fast charging and thermal runaway of high-nickel cells. Dual-vertical cooling can cool both sides of the cell simultaneously, ensuring the heat dissipation requirements for ultra-fast charging. In addition, liquid cooling plates are placed between every two battery cells in dual-vertical cooling solutions, ensuring rapid heat removal from the cell in the event of thermal runaway and isolating heat transfer between cells, thus ensuring the achievement of the safety goal of no heat diffusion in the power battery system.

[0004] According to the working principle of lithium-ion batteries, the outer surface of a battery cell will expand and contract during charging and discharging. Throughout the entire life cycle, the outer surface of the battery cell will gradually expand. The expansion and contraction of the battery cell caused by cyclic charging and discharging during the life cycle will inevitably have a positive fatigue effect on the liquid cooling plate. Existing liquid cooling plates have the risk of fatigue failure during their life cycle. Once the liquid cooling plate fails due to fatigue, it will lead to the leakage of coolant in the power battery system, ultimately causing safety problems in the power battery system. Summary of the Invention

[0005] The purpose of this application is to provide a liquid cooling plate, a liquid cooling plate design method, and a power battery, so as to solve to some extent the technical problem in the prior art that battery expansion and compression of the cold plate can easily lead to fatigue failure of the cold plate and leakage.

[0006] This application provides a liquid-cooled plate, comprising: The main body of the cold plate is in the shape of a long strip and includes a cooling surface. The number of cooling surfaces is at least one, and the cooling surface is used to be attached to the battery cell. A reinforcing connector is provided, wherein a flow cavity for coolant is formed inside the main body of the cold plate, the reinforcing connector is disposed in the flow cavity, and the reinforcing connector is connected to the side surface of the cooling surface facing the inside of the flow cavity; The reinforcing connector divides the flow cavity into at least two chambers within the flow cavity. The at least two chambers include interconnected flow channels and cooling channels, with the cooling channels located between the cooling surface and the reinforcing connector.

[0007] In the above technical solution, the main body of the cold plate further includes: A first plate component and a second plate component are arranged facing each other. The surface of the first plate component facing away from the second plate component is the cooling surface, and the surface of the second plate component facing away from the first plate component is the cooling surface. A first side plate and a second side plate are arranged facing each other, and the first side plate and the second side plate are respectively connected to the first plate component and the second plate component. In any of the above technical solutions, the number of reinforcing connectors is two, and each reinforcing connector is plate-shaped; the reinforcing connector includes a first connecting edge and a second connecting edge, wherein the first connecting edge and the second connecting edge of one reinforcing connector are respectively connected to the first plate component, and the first connecting edge and the second connecting edge of the other reinforcing connector are respectively connected to the second plate component.

[0008] In any of the above technical solutions, the reinforcing connector is further characterized by an arc; the middle position of one of the reinforcing connectors arches away from the first plate component; the middle position of the other reinforcing connector arches away from the second plate component.

[0009] In any of the above technical solutions, the cooling channel is further formed between the reinforcing connector and the first plate component, another cooling channel is formed between the reinforcing connector and the second plate component, and the flow channel is formed between the two reinforcing connectors.

[0010] In any of the above technical solutions, both the first plate component and the second plate component have a flat plate structure; Both the first side plate and the second side plate are arc-shaped plates, and the first side plate and the second side plate arch outward toward the flow cavity.

[0011] In any of the above technical solutions, the liquid cooling plate further includes: A first end plate and a second end plate are disposed facing each other. The first end plate is disposed at one end of the first plate component and is connected to both the first plate component and the second plate component. The second end plate is disposed at the other end of the first plate component and is connected to both the first plate component and the second plate component. A liquid inlet assembly is disposed on the first end plate and is used to inject the coolant into the flow chamber; A liquid outlet assembly is disposed on the second end plate and is used to supply the coolant to flow out. This application also provides a liquid cooling plate design method, applicable to the liquid cooling plate described in any of the above technical solutions, and thus possesses all the beneficial technical effects of the liquid cooling plate, which will not be elaborated here.

[0012] The liquid cooling plate design method includes the following steps: Step 100: Confirm the dimensions of the battery cell and the thickness of the components between two adjacent battery cells; Step 200: Confirm the design parameters of the liquid cooling plate to avoid interference between the liquid cooling plate and the battery cell; Step 300: Design the thickness and cross-section of the liquid cooling plate flow cavity.

[0013] In the above technical solution, step 300 further includes the following step: Step 301: Obtain the expansion displacement curve of the liquid cooling plate; Step 302: Obtain the design value of the wall thickness of the liquid cooling plate; Step 303: Determine the distance between the first reinforcing connector and the second reinforcing connector inside the liquid cooling plate; Step 304: Perform damage simulation on the liquid cooling plate; Step 305: Perform thermal management condition simulation; The design parameters of the liquid cooling plate were adjusted based on the simulation results.

[0014] This application also provides a liquid cooling plate design method, which includes the liquid cooling plate described in any of the above technical solutions, and thus has all the beneficial technical effects of the liquid cooling plate, which will not be repeated here.

[0015] The number of liquid cooling plates is multiple; the liquid cooling plate design method further includes: Multiple battery cells, each of which includes a large battery surface, and each of the large battery surfaces of the battery cells is provided with the liquid cooling plate, the cooling surface being in contact with the large battery surface; The housing; multiple liquid cooling plates and multiple battery cells are all disposed within the housing.

[0016] Compared with the prior art, the beneficial effects of this application are as follows: The liquid cooling plate provided in this application includes: a cooling plate body, which is in the shape of a long strip and includes a cooling surface, the number of which is at least one, and the cooling surface is used to adhere to a battery cell; a reinforcing connector, wherein a flow cavity for coolant flow is formed inside the cooling plate body, the reinforcing connector is disposed in the flow cavity, and the reinforcing connector is connected to the side surface of the cooling surface facing the inside of the flow cavity; the reinforcing connector divides the flow cavity into at least two chambers, the at least two chambers including a flow channel and a cooling channel that communicate with each other, the cooling channel being located between the cooling surface and the reinforcing connector.

[0017] The liquid cooling plate provided in this application, through structural optimization design, adds reinforcing connectors inside the main body of the cooling plate, which can increase the support for the cooling surface on the opposite side of the battery cell, reduce the stress deformation of the main body of the cooling plate caused by the expansion of the battery cell, and reduce the risk of leakage due to long-term fatigue of the main body of the cooling plate, thus extending the service life of the liquid cooling plate.

[0018] The liquid cooling plate design method provided in this application is applicable to the above-mentioned liquid cooling plate. In terms of liquid cooling plate design, the expansion force threshold-expansion displacement curve of the battery cell during its service life is used as the design input to design the structural scheme of the liquid cooling plate, ensuring that the liquid cooling plate can meet the fatigue requirements of compression and rebound caused by the expansion and contraction of the battery cell, and significantly reducing the risk of fatigue failure of the liquid cooling plate.

[0019] The power battery provided in this application can meet the heat dissipation requirements of each battery cell through the aforementioned liquid cooling plate, perform thermal management on each battery cell, and have good fatigue resistance to the stress exerted on the liquid cooling plate by the expansion and contraction of each battery cell, effectively reducing the risk of liquid leakage of the liquid cooling plate and improving the service life and safety performance of the power battery. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the liquid cooling plate provided in an embodiment of this application; Figure 2 Another schematic diagram of the structure of the liquid cooling plate provided in the embodiment of this application; Figure 3 A schematic diagram of the cross-sectional structure of the liquid cooling plate provided in the embodiments of this application; Figure 4 A schematic diagram of the cross-sectional structure of the liquid cooling plate provided in this application embodiment after being subjected to the expansion and compression of a battery cell; Figure 5 This is another structural schematic diagram of the liquid cooling plate provided in an embodiment of this application; Figure 6 This is a schematic diagram of the liquid cooling plate provided in an embodiment of this application from another perspective. Figure 7 This is a partial structural schematic diagram of the liquid cooling plate provided in an embodiment of this application; Figure 8 A schematic diagram of another part of the structure of the liquid cooling plate provided in the embodiments of this application; Figure 9 This is a schematic diagram of the layout structure of the liquid cooling plate and the battery cell provided in the embodiments of this application; Figure 10 The expansion force threshold-expansion displacement curve of a single battery cell in the liquid cooling plate design method provided in the embodiments of this application; Figure 11 This is a schematic diagram of the structure of a power battery provided in an embodiment of this application.

[0022] Figure label: 1-Liquid cooling plate; 101-First plate component; 102-Second plate component; 103-First side plate; 104-Second side plate; 105-First end plate; 106-Second end plate; 3-First reinforcing connector; 4-Second reinforcing connector; 5-Flow channel; 6-Cooling channel; 7-First water inlet; 8-Second water inlet; 9-First water outlet; 10-Second water outlet; 11-Battery cell; 12-Heat conductive component; 13-Upper housing; 14-Lower housing; 15-Liquid cooling module; 16-Control module; 17-Sensor module; 18-Safety protection module; 19-Internal high-voltage connection module; 20-Internal low-voltage connection module; 21-High-voltage execution module; 22-External high-voltage connection module; 23-External low-voltage connection module; 24-External coolant connection module. Detailed Implementation

[0023] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0024] The components of the embodiments of this application described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application.

[0025] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0028] The following reference Figures 1 to 11 This application describes the liquid cooling plate, liquid cooling plate design method, and power battery as described in the embodiments.

[0029] Firstly, see [the following] Figures 1 to 10 As shown in the figure, an embodiment of this application provides a liquid cooling plate, which includes a cooling plate body and reinforcing connectors. The cooling plate body includes multiple wall panels, some of which have outer walls that serve as cooling surfaces. These cooling surfaces are used to adhere to the battery cells 11, thereby achieving heat dissipation and cooling of the battery cells 11. A flow cavity is formed inside the cooling plate body for the circulation of coolant, allowing the heat transferred from the battery cells 11 to the cooling plate body to be absorbed by the coolant. The reinforcing connectors are disposed within the flow cavity and are connected to the back side of the cooling surfaces within the flow cavity. This allows the reinforcing connectors to support the wall panels with the cooling surfaces, thereby improving the structural strength and external force resistance of the cooling plate body. This reduces the risk of fatigue failure and subsequent cracking or damage to the cooling plate body when the battery cells 11 expand and act on it. The reinforcing connector divides the internal space of the flow cavity into at least two parts, forming at least two interconnected chambers within the flow cavity, both of which receive coolant. Each chamber includes at least a flow channel 5 and a cooling channel 6. The chamber between the inner wall of the cooling surface and the reinforcing connector is the cooling chamber. When the coolant flows within the cooling chamber, it absorbs and carries away the heat transferred to the cooling surface. By providing the reinforcing connector within the flow cavity, not only can the compressive strength, deformation resistance, and fatigue resistance of the cooling surface be increased, but the turbulence effect on the coolant can also be increased, adjusting the flow path of the coolant and improving the heat dissipation effect on the battery cell 11, thereby improving the safety of the battery cell 11.

[0030] Specifically, the cold plate body includes: a first plate component 101, a second plate component 102, a first side plate 103, and a second side plate 104. The first plate component 101 and the second plate component 102 are arranged facing each other, and the first side plate 103 and the second side plate 104 are also arranged facing each other. The first side plate 103 is located between one side of the first plate component 101 and one side of the second plate component 102, and the second side plate 104 is located between the other side of the first plate component 101 and the other side of the second plate component 102. Preferably, the first plate component 101, the first side plate 103, and the second plate component 104 are arranged in a specific configuration. 102 and the second side plate 104 are integrally formed to have an integral structure, and the four together form a cylindrical structure with openings at both ends. The first plate component 101 and the second plate component 102 have the same first dimension, and the first side plate 103 and the second side plate 104 have the same second dimension. The first dimension is larger than the second dimension. It should be noted that the first dimension and the second dimension include the length and width of the corresponding plate components. The surfaces of the first plate component 101 and the second plate component 102 that are opposite to each other are both cooling surfaces, or the outer surfaces of the first plate component 101 and the second plate component 102 are both cooling surfaces. Optionally, in this embodiment, the battery cell 11 has a cuboid shape, and the cooling surface is specifically the large surface of the cold plate body. The cooling surface is in contact with the large surface of the battery cell 11 to ensure the effective contact area between the liquid cooling plate and the battery cell 11, and to ensure the cooling effect on the battery cell 11.

[0031] Preferably, both the first side plate 103 and the second side plate 104 are arc-shaped plates. The first side plate 103 is bent and arched towards the outer space of the flow cavity, and the second side plate 104 is bent and arched towards the outer space of the flow cavity. This can reduce the impact of the coolant on the first side plate 103 and the second side plate 104 to a certain extent and extend the service life of the first side plate 103 and the second side plate 104.

[0032] Furthermore, the main body of the cold plate also includes: a first end plate 105 and a second end plate 106. The first end plate 105 is disposed at the same end of the first plate component 101 and the second plate component 102, and the first end plate 105 blocks one end opening of the above-mentioned cylindrical structure. The second end plate 106 is disposed at the other end of the first plate component 101 and the second plate component 102, and the second end plate 106 blocks the other end opening of the cylindrical structure, so that a sealed cavity is formed inside the main body of the cold plate to prevent coolant from overflowing.

[0033] The first end plate 105 is provided with a first connection port, and a first flow channel is formed inside the first end plate 105. The first connection port is connected to the flow cavity through the first flow channel. The second end plate 106 is provided with a second connection port, and a second flow channel is formed inside the second end plate 106. The second connection port is connected to the flow cavity through the second flow channel.

[0034] Furthermore, this liquid-cooled plate also includes a liquid inlet assembly and a liquid outlet assembly. The liquid inlet assembly is disposed at the first connection port, and the liquid outlet assembly is disposed at the second connection port. Specifically, the liquid inlet assembly includes a first water inlet 7 and a second water inlet 8, and the liquid outlet assembly includes a first water outlet 9 and a second water outlet 10. The first water inlet 7, the first connection port, and the first water outlet 9 are coaxially arranged, and the second water inlet 8, the second connection port, and the second water outlet 10 are coaxially arranged. The first water inlet 7 and the second water inlet 8 are used to supply coolant into the flow chamber, and the first water outlet 9 and the second water outlet 10 are used to allow the coolant in the flow chamber to flow out, so that the coolant in the flow chamber can circulate. When this liquid-cooled plate is used alone, the first water inlet 7 and the second water inlet can be connected to a coolant supply source through a liquid inlet pipe.

[0035] When multiple liquid cooling plates are used in combination, the multiple liquid cooling plates are arranged in sequence with intervals, and the large surfaces of two adjacent liquid cooling plates are set facing each other. The first water inlet 7 of each liquid cooling plate 1 can be connected to the first water outlet 9 of the adjacent liquid cooling plate 1, and the second water inlet 8 can be connected to the second water outlet 10 of the adjacent liquid cooling plate 1, so that the multiple liquid cooling plates are connected and communicated in sequence. In this case, any two adjacent main supports of the cooling plates form an installation space for placing the battery cell 11.

[0036] Similarly, the first water outlet 9 and the second water outlet 10 can be connected to the liquid storage container through the liquid outlet pipe or flow back to the coolant supply source after heat exchange. Alternatively, when multiple liquid cooling plates are used in combination, the first water outlet 9 of each liquid cooling plate can be connected to the second water outlet 10 of the adjacent liquid cooling plate, and the second water outlet 10 of each liquid cooling plate can be connected to the first water outlet 9 of the adjacent liquid cooling plate.

[0037] Furthermore, there are two reinforcing connectors: a first reinforcing connector 3 and a second reinforcing connector 4. Both the first reinforcing connector 3 and the second reinforcing connector 4 are elastic and have the same structure. They are symmetrically arranged in the flow cavity. The length of the first reinforcing connector 3 is the same as the length of the second reinforcing connector 4, both being less than the length of the first plate component 101 and also less than the length of the second plate component 102. The first reinforcing connector 3 is plate-shaped and has an arc. The first reinforcing connector 3 is connected to the inner wall of the first plate component 101 in the flow cavity. The length of the first reinforcing connector 3 extends along the length direction of the first plate component 101. The two sides of the first reinforcing connector 3 along its width direction are respectively a first connecting edge and a second connecting edge. The first connecting edge and the second connecting edge are respectively connected to the inner wall of the first plate component 101. The plate surface of the first reinforcing connector 3 located between the first connecting edge and the second connecting edge arches towards the second plate component 102. The second reinforcing connector 4 is connected to the inner wall of the second plate component 102 in the same manner, which is fully understandable to those skilled in the art.

[0038] With the aforementioned arrangement of the first reinforcing connector 3 and the second reinforcing connector 4, the first reinforcing connector 3 and the second reinforcing connector 4 arch towards each other, but do not contact each other. They are spaced apart, forming a cooling channel 6 between the first plate component 101 and the first reinforcing connector 3, a flow channel 5 between the first reinforcing connector 3 and the second reinforcing connector 4, and another cooling channel 6 between the second reinforcing connector 4 and the second plate component 102. Since the length of the first reinforcing connector 3 is less than the length of the first plate component 101, and the length of the second reinforcing connector 4 is less than the length of the second plate component 102... The length of 02 allows the flow channel 5 and the two cooling channels 6 to be interconnected. When the coolant enters the flow chamber through the first water inlet 7 and / or the second water inlet 8, it can be diverted and flow into the flow channel 5 and the two cooling channels 6 respectively. The coolant in the cooling channel 6 can carry away the heat of the first plate component 101 and the second plate component 102, so as to play the role of heat absorption and heat dissipation. The coolant in the flow channel 5 can play the role of heat dissipation for the first reinforcing connector 3 and the second reinforcing connector 4, and can also apply a certain pressure to the first reinforcing connector 3 and the second reinforcing connector 4 to avoid the first reinforcing connector 3 and the second reinforcing connector 4 being subjected to force on one side, which would generate fatigue stress over time.

[0039] Furthermore, it should be noted that gaps are formed between the first reinforcing connector 3 and the first plate component 101, and between the second reinforcing connector 4 and the second plate component 102. Figure 6The gap size shown is for illustrative purposes only and does not represent the actual dimensions. When the first plate component 101 or the second plate component 102 is compressed by the expansion of the battery cell 11, causing deformation of the first plate component 101 or the second plate component 102, the first reinforcing connector 3 and the second reinforcing connector 4 may approach or even contact each other. This can improve the support effect after the deformation of the first plate component 101 or the second plate component 102 and limit further deformation of the first plate component 101 or the second plate component 102. When the first reinforcing connector 3 and the second reinforcing connector 4 are compressed and deformed, they can also exert a reverse action on the first plate component 101 and the second plate component 102, causing the first plate component 101 and the second plate component 102 to tend to fit towards the battery cell 11. When the battery cell 11 contracts, the compression on the first plate component 101 and / or the second plate component 102 weakens or disappears, and the elasticity of the first reinforcing connector 3 and the second reinforcing connector 4... Under the action of the reinforcement, the first plate component 101 or the second plate component 102 can be reset to a certain extent. The expansion degree of the battery cell 11 is usually limited. That is to say, the deformation of the first plate component 101 and the second plate component 102 under the pressure will not be large. Therefore, under ideal conditions, the first plate component 101 or the second plate component 102 can return to its original position under the elastic support of the reinforcement connector to fit with the battery cell 11. It can be seen that by setting two reinforcement connectors, the battery cell 11 is compressed and rebounded to a certain extent during expansion and contraction, which ensures the heat dissipation effect. At the same time, based on the special structural design, fatigue failure is guaranteed throughout the entire life cycle, thereby reducing the risk of damage and leakage of the liquid cooling plate due to excessive deformation of the first plate component 101 and / or the second plate component 102. It does not affect the normal flow of the coolant in the two cooling channels 6, ensuring the heat absorption and dissipation effect of the first plate component 101 and the second plate component 102.

[0040] In summary, the liquid cooling plate provided in this application, through structural optimization design and the addition of reinforcing connectors within the main body of the cooling plate, can increase support for the cooling surface on the opposite side of the battery cell 11, reduce the stress deformation of the main body of the cooling plate caused by the expansion of the battery cell 11, and reduce the risk of leakage due to long-term fatigue of the main body of the cooling plate, thus extending the service life of the liquid cooling plate. In addition, the reinforcing connectors can also play a turbulent role in the coolant within the main body of the cooling plate, improving the fluidity of the coolant, thereby improving the heat dissipation effect on the cooling surface and the battery cell 11 in contact with the cooling surface.

[0041] Secondly, embodiments of this application also provide a liquid cooling plate design method, applicable to the liquid cooling plate described in any of the above embodiments, and thus possessing all the beneficial technical effects of the liquid cooling plate, which will not be repeated here.

[0042] Since the design function of the liquid cooling plate 1 is to ensure that the battery cell 11 does not overheat under various operating conditions, the dimensional parameters and expansion and displacement curves of the battery cell 11 are important inputs for the design of the liquid cooling plate 1. This liquid cooling plate design method includes the following steps: Step 100, in the power battery system using the above-mentioned liquid cooling plate, such as Figure 9 As shown, the same number of battery cells 11 are arranged on both sides of each liquid cooling plate 1. According to the arrangement scheme of battery cells 11 in the power battery system, the height H of the battery cells 11 arranged on one side of the liquid cooling plate 1 is determined. 单体 Length L 单体 11 battery cells, quantity M 单体 And the thickness L of the components located between the 11 battery cells 部件 .

[0043] Step 200: To ensure the appropriate height of the liquid cooling plate 1 and prevent interference with the high and low voltage connection modules on the upper part of the battery cell 11 and the lower casing 14, a safety factor K is adopted in the design. 安全1 The maximum width L1 of the flow cavity portion of the liquid cooling plate 1 is designed and calculated using the following formula (Formula 1). The lengths L9 of the first end plate 105 and the second end plate 106 of the liquid cooling plate 1 are designed to match L1. For ease of description, the length (or height) direction of the main body of the cold plate is defined as the first direction, the width direction of the main body of the cold plate is defined as the second direction, and the thickness direction of the main body of the cold plate is defined as the third direction. Then, the maximum length of the flow cavity distributed along the first direction is L1, and the length of the first end plate 105 and the second end plate 106 distributed along the second direction is L9.

[0044] To meet welding and sealing requirements, a safety factor K is used. 安全2 The design and calculation formula are as follows: Formula 2. The liquid cooling plate 1 needs to provide thermal management for all adjacent battery cells 11, therefore, the length L of its flow cavity portion... 10 A safety factor of K (safety 3) needs to be adopted, taking into account the length L of each battery cell (11). 单体 Number of individual units M 单体 Thickness L of components between 11 battery cells 部件 The calculation formula is as follows: Formula 3. The length L7 of the first end plate 105 and the second end plate 106 along the first direction needs to ensure that the battery cell 11 does not interfere with the liquid inlet or liquid outlet components installed between the liquid cooling plate 1. Therefore, it needs to be based on the safety factor K. 安全4 and the maximum diameter of the inlet assembly and the maximum diameter L of the outlet assembly 11The design and calculation formulas are as follows: Formula 4. The calculation formula for the total length L6 of the liquid cooling plate 1 is as follows: Formula 5. According to the design plan, the wall thicknesses of the first side plate 103, the second side plate 104, the first plate component 101, the second plate component 102, the first reinforcing connector 3, and the second reinforcing connector 4 of the flow cavity are confirmed. Optionally, the wall thicknesses of the first side plate 103, the second side plate 104, the first plate component 101, the second plate component 102, the first reinforcing connector 3, and the second reinforcing connector 4 are the same, all being L. 壁厚 .

[0045]

[0046] Step 300: After completing the main body size design of the liquid cooling plate 1, it is necessary to design the thickness and cross-section of the flow cavity part of the liquid cooling plate 1.

[0047] Step 301: To ensure that the flow cavity of the liquid cooling plate 1 can absorb the expansion of the battery cell 11, it is necessary to follow the expansion force threshold-expansion displacement curve of the battery cell 11 (as follows). Figure 10 Confirm the maximum acceptable clamping force F of the battery cell in state 11. 单体阈值 and the limiting expansion size L EOL The expansion force threshold-expansion displacement curve of battery cell 11 represents the expansion displacement L of battery cell 11 under a certain state during its life cycle. 膨胀 The maximum acceptable clamping force F under this condition 单体 The relationship.

[0048] Step 302: Based on the operating conditions throughout the entire life cycle of the power battery system, confirm the thermal management requirements of the battery cell 11. Calculate the coolant flow rate requirement using Formula 6, where Q is the heat to be exchanged by the battery cell 11, ρ is the coolant density, V is the volume of coolant in the liquid cooling plate 1, C is the specific heat capacity of the coolant, and ΔT is the temperature change of the coolant to achieve the heat exchange Q of the battery cell 11. Combined with the required flow resistance R of the vehicle, confirm the inner cavity dimension L4 of the flow cavity portion of the liquid cooling plate 1. The overall thickness of the flow cavity portion of the liquid cooling plate 1 can then be obtained as: L4 + 2 × L 壁厚 At this point, the cross-sectional envelope of the flow cavity portion of liquid-cooled plate 1 can be obtained, that is, the height is L1 and the thickness is L4+2×L. 壁厚 A rectangle, such as Figure 5 The dashed area in the diagram is within the envelope of the shape curves of the subsequent first side plate 103 and second side plate 104. The thickness L8 of the first end plate 105 and second end plate 106 of the liquid cooling plate 1 is based on the safety factor K. 安全5 and the thickness of the flow cavity of liquid cooling plate 1 (L4+2×L) 壁厚 The design and calculation formula is as follows: Formula 7.

[0049]

[0050] Step 303: Based on the expansion force threshold-expansion displacement curve of the battery cell 11, the number of cycles N in the life cycle of the battery cell 11, and the material properties of the flow cavity portion of the liquid cooling plate 1, confirm the shape spline curves B1 of the first side plate 103 and the second side plate 104, confirm the shape spline curves B2 of the first reinforcing connector 3 and the second reinforcing connector 4; confirm the distance L5 between the first reinforcing connector 3 and the second reinforcing connector 4; confirm the length L2 of the first plate component 101 and the second plate component 102 along the second direction; confirm the distance L3 between the first side plate 103 and the first reinforcing connector 3 and the second reinforcing connector 4, and between the second side plate 104 and the first reinforcing connector 3 and the second reinforcing connector 4 in the second direction.

[0051] Step 304: Perform damage simulations under conditions including but not limited to vibration and transmission system durability conditions, which involve strong impact loads, to confirm the damage value of the liquid cooling plate 1. If the damage value S1 of the liquid cooling plate 1 is less than or equal to the damage threshold S of the liquid cooling plate 1... 阈值 If the condition is met, proceed to step 305; otherwise, proceed to step 307.

[0052] Step 305: Perform thermal management condition simulation to confirm the highest temperature of battery cell 11 (it should be noted that the highest temperature here is the highest temperature that can be detected, and may not be the same as the critical highest temperature value at which battery cell 11 will experience thermal runaway). If the highest temperature T1 of battery cell 11 is less than or equal to the temperature threshold T of battery cell 11... 阈值 If yes, proceed to step 306; otherwise, proceed to step 308.

[0053] Step 306: Perform fatigue life simulation to confirm the fatigue value of liquid cooling plate 1. The fatigue value of liquid cooling plate 1, б, is less than or equal to the fatigue strength, б, of liquid cooling plate 1. 阈值 If the design of liquid cooling plate 1 is successful, then the design is complete; otherwise, proceed to step 309.

[0054] Step 307: The wall thickness of the liquid cooling plate 1 material is designed and optimized before proceeding to step 303, because the wall thickness affects the thickness of the flow cavity portion of the liquid cooling plate 1.

[0055] Step 308, because the shape curves of the first side plate 103 and the second side plate 104 are at a height of L1 and a thickness of L4+2×L 壁厚 The design is carried out within the rectangular envelope, meaning the actual flow cavity size used in the thermal management simulation in step 306 must be smaller than the length L1 and the thickness L4+2×L. 壁厚 The rectangular envelope of the liquid cooling plate 1, and the design of the inner cavity dimensions based on the coolant flow rate and flow resistance, are based on a height of L1 and a thickness of L4+2×L. 壁厚The design is based on a rectangular envelope, which means that the actual flow channel size of the liquid cooling plate 1 does not meet the operating requirements. Therefore, it is necessary to optimize the inner cavity size L4 of the flow cavity of the liquid cooling plate 1 before proceeding to step 302.

[0056] Step 309: Optimize the shape spline curve B1 of the first side plate 103 and the second side plate 104; optimize the shape spline curve B2 of the first reinforcing connector 3 and the second reinforcing connector 4; optimize the spacing L5 between the first reinforcing connector 3 and the second reinforcing connector 4; optimize the height L2 of the first plate component 101 and the second plate component 102; optimize parameter L3, and then proceed to step 305.

[0057] It should be noted that the safety factors mentioned above are the requirements parameters of relevant regulations in the power battery industry. All of these parameters are considered to be known data to ensure that the power battery meets the relevant requirements and standards.

[0058] The liquid cooling plate design method provided in this application uses the expansion force threshold-expansion displacement curve of the battery cell 11 during its service life as the design input to design the liquid cooling plate 1. This ensures that the liquid cooling plate 1 can meet the fatigue requirements of compression and rebound caused by the expansion and contraction of the battery cell 11, and significantly reduces the risk of fatigue failure of the liquid cooling plate 1.

[0059] Thirdly, referring to Figure 11 As shown, embodiments of this application also provide a power battery including multiple liquid cooling plates as described in the above embodiments, thus possessing all the beneficial technical effects of the liquid cooling plate, which will not be repeated here.

[0060] This power battery also includes a housing and multiple battery cells 11. Multiple liquid cooling plates and multiple battery cells 11 are all disposed within the housing. The housing specifically includes an upper housing 13 and a lower housing 14 that can be interlocked. Multiple battery cells 11 are arranged in a matrix in at least two rows and at least two columns within the lower housing 14. Each battery cell 11 has a liquid cooling plate on both sides. Preferably, the length of the liquid cooling plate is greater than the length of the battery cell 11, so that multiple battery cells 11 can share a single liquid cooling plate on the same side. After the multiple liquid cooling plates and multiple battery cells 11 are installed in sequence, and after the following modules are installed in place, the upper housing 13 and the lower housing 14 are interlocked and connected to form a sealed space inside the housing, thus completing the encapsulation of this power battery.

[0061] Preferably, the power battery further includes multiple heat-conducting components 12, which are disposed between the large surface of the liquid cooling plate and the large surface of the battery cell 11 to improve the heat conduction efficiency between the battery cell 11 and the liquid cooling plate. The heat-conducting components 12 can be thermal adhesive, thermal pads, etc.

[0062] Furthermore, this power battery also includes a liquid cooling module 15, which includes an inlet pipe, an inlet connector, an outlet pipe, and an outlet connector. The inlet connector and the outlet connector are respectively arranged on the wall panel of the lower housing 14. The inlet pipe is located inside the lower housing 14 and is connected to the inlet connector. After the inlet components of multiple liquid cooling plates arranged in each row are connected in sequence, the inlet components located at the first and last positions of the row are connected to the inlet pipe, so that liquid can be supplied to each liquid cooling plate through the inlet connector and the inlet pipe. The outlet pipe is located inside the lower housing 14 and is connected to the outlet connector. After the outlet components of multiple liquid cooling plates arranged in each row are connected in sequence, the outlet components located at the first and last positions of the row are connected to the outlet pipe, so that the coolant in each liquid cooling plate can flow out through the outlet pipe and the outlet connector, thereby realizing the circulation of coolant.

[0063] Furthermore, this power battery also includes a control module 16, a sensor module 17, a safety protection module 18, an internal high-voltage connection module 19, an internal low-voltage connection module 20, and a high-voltage execution module 21, all housed within the battery pack. The internal high-voltage connection module 19 connects the individual battery cells 11 within the pack in series and parallel according to the vehicle's operating voltage requirements, and connects to the external high-voltage connection module 22. The sensor module 17 is located at a specific position within the pack and is used to collect signals including, but not limited to, voltage, current, temperature, and internal air pressure. The internal low-voltage connection module 20 connects the sensor module 17, the control module 16, and the external low-voltage connection module 23 for signal transmission and interaction. The safety protection module 18 is located at a specific position within the pack for internal safety protection. The high-voltage execution module 21 is connected in series in the internal high-voltage circuit of the internal high-voltage connection module, and its operating state is controlled by the control module 16 to disconnect and connect the internal high voltage. The control module 16 is connected to the sensor module 17, the high-voltage execution module 21, and the external low-voltage connection module 23 through the internal low-voltage connection module 20. It is used to collect and process the signals collected by the sensor module 17 and to interact with the vehicle control module 16.

[0064] Furthermore, this power battery also includes an external high-voltage connection module 22 and an external low-voltage connection module 23. The external high-voltage connection module 22 and the external low-voltage connection module 23 are disposed on the outer wall of the upper housing 13. The external high-voltage connection module 22 connects to the internal high-voltage connection module on one side and to the high-voltage module of the vehicle on the other side, connecting the battery pack to the high-voltage circuit of the vehicle, enabling the power battery system to perform charging and discharging functions. The external low-voltage connection module 23 connects to the internal low-voltage connection module on one side and to the low-voltage connection module of the vehicle on the other side, connecting the battery pack to the low-voltage circuit of the vehicle, allowing the power battery system to communicate with the vehicle via low-voltage signals.

[0065] Furthermore, this power battery also includes an external coolant connection module 24, which is arranged on the housing. One side of the module is connected to the liquid cooling module 15 inside the battery pack, and the other side is connected to the cooling circuit of the vehicle. This module is used to connect the cooling circuit of the power battery system with the cooling circuit of the vehicle and to perform thermal management on the battery cells 11.

[0066] As can be seen, each battery cell 11 has liquid cooling plates on both sides, employing a dual-surface cooling scheme to achieve rapid heat dissipation. This power battery system can be used with high-rate fast-charging battery cells 11 to develop ultra-fast charging battery systems, and can also be used with high-nickel battery cells 11 to develop long-range battery systems. This allows for diversified development to meet different needs by changing the battery cell system within the same design, increasing the scalability of the power battery system. Regarding the power battery system design methodology, the parameters of the power battery system are designed in detail based on the overall vehicle design specifications to meet the vehicle's requirements.

[0067] Furthermore, this power battery can perform the following operations during the design phase: The design method for the power battery system using the aforementioned liquid cooling plate 1 takes the overall vehicle performance requirements as a premise. Within the allowable space envelope, the dimensions and functions of each module within the power battery system are designed to meet the overall vehicle performance requirements. The design process of the power battery system is as follows: Step 1: Confirm the input envelope dimensions of the vehicle and the layout requirements of the external high-voltage connection module 22, external low-voltage connection module 23, and external coolant connection module 24 of the power battery system.

[0068] Step 2: Confirm the list of input functions for the entire vehicle.

[0069] Step 3, confirm the vehicle input performance list, which includes, but is not limited to, the power requirement (W). 电量 Operating voltage range (V) 系统min V 系统max Fast charging time T 快充 .

[0070] Step 4, according to the required power consumption (W) 电量 Operating voltage range (V) 系统min V 系统max Fast charging time T 快充 Functional parameters such as the system structure and operating voltage range (V) of battery cell 11 in the battery cell 11 module are confirmed. 单体min V 单体max ), quantity N 单体 .

[0071] Step 5: Based on the platform-based design concept and previous design experience, confirm the arrangement matrix of the 11 battery cells in the power battery system, that is, arrange the number N of 11 battery cells along the vehicle's driving direction in the power battery system. 单体1 11 battery cells arranged perpendicular to the vehicle's direction of travel in a horizontal plane, with a quantity of N. 单体2 The number of individual units arranged meets the requirements of Formula 8.

[0072]

[0073] Step 6: Based on the size breakdown, design the size parameters of each module.

[0074] Step 7: Design the functional parameters of each module.

[0075] Step 8: Verify the dimensions and functional parameters of each module. If they are satisfactory, the design is complete; otherwise, proceed to step 9.

[0076] Step 9: Optimize the size and functional parameters of each module, and then proceed to step 8.

[0077] In summary, the power battery provided in this application can meet the heat dissipation requirements of each battery cell 11 through the aforementioned liquid cooling plate, perform thermal management on each battery cell 11, and have good fatigue resistance to the stress exerted on the liquid cooling plate by the expansion and contraction of each battery cell 11, effectively reducing the risk of liquid leakage of the liquid cooling plate and improving the service life and safety performance of the power battery.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A liquid-cooled plate, characterized in that, include: The main body of the cold plate is in the shape of a long strip and includes a cooling surface. The number of cooling surfaces is at least one, and the cooling surface is used to be attached to the battery cell. A reinforcing connector is provided, wherein a flow cavity for coolant is formed inside the main body of the cold plate, the reinforcing connector is disposed in the flow cavity, and the reinforcing connector is connected to the side surface of the cooling surface facing the inside of the flow cavity; The reinforcing connector divides the flow cavity into at least two chambers within the flow cavity. The at least two chambers include interconnected flow channels and cooling channels, with the cooling channels located between the cooling surface and the reinforcing connector.

2. The liquid cooling plate according to claim 1, characterized in that, The main body of the cold plate includes: A first plate component and a second plate component are arranged facing each other. The surface of the first plate component facing away from the second plate component is the cooling surface, and the surface of the second plate component facing away from the first plate component is the cooling surface. A first side plate and a second side plate are arranged facing each other, and the first side plate and the second side plate are respectively connected to the first plate component and the second plate component.

3. The liquid cooling plate according to claim 2, characterized in that, The number of reinforcing connectors is two, and each reinforcing connector is plate-shaped; the reinforcing connector includes a first connecting edge and a second connecting edge, wherein the first connecting edge and the second connecting edge of one reinforcing connector are respectively connected to the first plate component, and the first connecting edge and the second connecting edge of the other reinforcing connector are respectively connected to the second plate component.

4. The liquid cooling plate according to claim 2, characterized in that, The reinforcing connectors are curved; one of the reinforcing connectors arches in the middle position toward the direction away from the first plate component; the other reinforcing connector arches in the middle position toward the direction away from the second plate component.

5. The liquid cooling plate according to claim 2, characterized in that, The cooling channel is formed between the reinforcing connector and the first plate component, another cooling channel is formed between the reinforcing connector and the second plate component, and the flow channel is formed between the two reinforcing connectors.

6. The liquid cooling plate according to claim 2, characterized in that, Both the first plate component and the second plate component have a flat plate structure; Both the first side plate and the second side plate are arc-shaped plates, and the first side plate and the second side plate arch outward toward the flow cavity.

7. The liquid cooling plate according to claim 2, characterized in that, The liquid cooling plate also includes: A first end plate and a second end plate are disposed facing each other. The first end plate is disposed at one end of the first plate component and is connected to both the first plate component and the second plate component. The second end plate is disposed at the other end of the first plate component and is connected to both the first plate component and the second plate component. A liquid inlet assembly is disposed on the first end plate and is used to inject the coolant into the flow chamber; A liquid outlet assembly is disposed on the second end plate and is used to supply the coolant to flow out.

8. A liquid cooling plate design method, characterized in that, Includes the following steps: Step 100: Confirm the dimensions of the battery cell and the thickness of the components between two adjacent battery cells; Step 200: Confirm the design parameters of the liquid cooling plate to avoid interference between the liquid cooling plate and the battery cell; Step 300: Design the thickness and cross-section of the liquid cooling plate flow cavity.

9. The liquid cooling plate design method according to claim 8, characterized in that, Step 300 further includes the following step: Step 301: Obtain the expansion displacement curve of the liquid cooling plate; Step 302: Obtain the design value of the wall thickness of the liquid cooling plate; Step 303: Determine the distance between the first reinforcing connector and the second reinforcing connector inside the liquid cooling plate; Step 304: Perform damage simulation on the liquid cooling plate; Step 305: Perform thermal management condition simulation; The design parameters of the liquid cooling plate were adjusted based on the simulation results.

10. A power battery, characterized in that, The liquid cooling plate includes any one of claims 1 to 7, wherein the number of liquid cooling plates is plurality of them; the liquid cooling plate design method further includes: Multiple battery cells, each of which includes a large battery surface, and each of the large battery surfaces of the battery cells is provided with the liquid cooling plate, the cooling surface being in contact with the large battery surface; The housing; multiple liquid cooling plates and multiple battery cells are all disposed within the housing.

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