Battery heat exchanger, battery pack and vehicle

Abstract

The invention discloses a battery heat exchanger, a battery pack and a vehicle, the battery heat exchanger comprises a branch and confluence structure, the branch and confluence structure comprises a first flow channel, a second flow channel and a third flow channel, the cross section area of the first flow channel is larger than that of the second flow channel, and the cross section area of the third flow channel is larger than that of the first flow channel. The area of the cross section of the first flow channel is larger than that of the cross section of the third flow channel; wherein the first flow channel is communicated with a first interface of the battery heat exchanger, and the second flow channel and the third flow channel are communicated with a second interface of the battery heat exchanger. The heat exchange performance of the battery heat exchanger can be improved.

Description

Technical Field

[0001] The present application belongs to the field of vehicle technology, and specifically, relates to a battery heat exchanger, a battery pack and a vehicle. Background Art

[0002] In the prior art, a battery heat exchanger is used to exchange heat for batteries in a battery pack.

[0003] The existing technology uses a harmonica tube as a battery heat exchanger, in which the heat exchange medium undergoes a gas-liquid phase change. Each flow channel of the harmonica tube is a straight tube, resulting in a large temperature difference between the temperature near the inlet and the temperature far from the inlet, which in turn causes uneven heat exchange of the battery. Therefore, it is necessary to optimize the flow channel of the battery heat exchanger. When the flow channel has a diversion or confluence function, the heat exchange medium will be diverted or converged in the heat exchanger. However, how to design a diversion and confluence structure, optimize the flow resistance of the heat exchange medium in different flow channels, and make the battery heat exchanger as uniform as possible to reduce the temperature difference between the various parts of the battery is an urgent problem to be solved. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a battery heat exchanger with good heat exchange performance.

[0005] According to a first aspect of an embodiment of the present application, a battery heat exchanger is provided, the battery heat exchanger comprising a branch-and-merge flow structure, the branch-and-merge flow structure comprising a first flow channel, a second flow channel and a third flow channel;

[0006] The cross-sectional area of ​​the first flow channel is greater than the cross-sectional area of ​​the second flow channel, and the cross-sectional area of ​​the first flow channel is greater than the cross-sectional area of ​​the third flow channel;

[0007] The first flow channel is communicated with a first interface of the battery heat exchanger, and the second flow channel and the third flow channel are communicated with a second interface of the battery heat exchanger.

[0008] Optionally, h1 / b∈[1 / 3, 10], wherein h1 is the maximum depth of the first flow channel, the second flow channel, or the third flow channel, and b is the thickness of the flow channel plate of the battery heat exchanger.

[0009] Optionally, h1 / s2∈[1 / 20,1], wherein h1 is the maximum depth of the first flow channel, the second flow channel, or the third flow channel, and s2 is the maximum width of the first flow channel, the second flow channel, or the third flow channel.

[0010] Optionally, h1 / r2∈[1 / 7,5 / 2], wherein h1 is the maximum depth of the first flow channel or the second flow channel or the third flow channel, and r2 is the radius of the second chamfer of the first flow channel or the second flow channel or the third flow channel close to the substrate of the battery heat exchanger.

[0011] Optionally, h1 / b∈[1 / 3, 10], h1 / s2∈[1 / 20, 1], h1 / r2∈[1 / 7, 5 / 2], wherein h1 is the maximum depth of the first channel or the second channel or the third channel, b is the thickness of the channel plate of the battery heat exchanger, s2 is the maximum width of the first channel or the second channel or the third channel, and r2 is the radius of the second chamfer of the first channel or the second channel or the third channel close to the substrate of the battery heat exchanger.

[0012] Optionally, h1 / b∈[1 / 3,5 / 1], h1 / s2∈[1 / 15,1 / 3], h1 / r2∈[1 / 7,2 / 5], wherein h1 is the maximum depth of the first channel or the second channel or the third channel, b is the thickness of the channel plate of the battery heat exchanger, s2 is the maximum width of the first channel or the second channel or the third channel, and r2 is the radius of the second chamfer of the first channel or the second channel or the third channel close to the substrate of the battery heat exchanger.

[0013] Optionally, a / s2≥0.05, wherein a is the thickness of the substrate of the battery heat exchanger, and s2 is the maximum width of the first flow channel, the second flow channel, or the third flow channel.

[0014] Optionally, s3 / s4∈[5 / 20,4], wherein s3 is the maximum width of the outer surface of the second flow channel, and s4 is the maximum width of the outer surface of the third flow channel.

[0015] Optionally, s3 / s4∈[1 / 3,3 / 1], wherein s3 is the maximum width of the outer surface of the second flow channel, and s4 is the maximum width of the outer surface of the third flow channel.

[0016] Optionally, s5≤15mm, s6≤45mm, wherein s5 is the maximum width of the outer surface of the first flow channel, and s6 is the minimum distance between any flow channel and the surrounding structure.

[0017] Optionally, when the flow dividing and converging structure is used for flow dividing, the fluid in the first flow channel is divided into the second flow channel and the third flow channel;

[0018] When the flow dividing and converging structure is used for converging flow, the fluids in the second flow channel and the third flow channel converge into the first flow channel.

[0019] Optionally, a cross-sectional area of ​​the second flow channel is equal to a cross-sectional area of ​​the third flow channel.

[0020] Optionally, r1≤r2, wherein r1 is the radius of a first chamfer of the first flow channel, the second flow channel, or the third flow channel away from the substrate of the battery heat exchanger, and r2 is the radius of a second chamfer of the first flow channel, the second flow channel, or the third flow channel close to the substrate of the battery heat exchanger.

[0021] Optionally, r1≤h1, wherein h1 is the maximum depth of the first flow channel, the second flow channel, or the third flow channel.

[0022] Optionally, a=b, wherein a is the thickness of the substrate of the battery heat exchanger, and b is the thickness of the flow channel plate of the battery heat exchanger.

[0023] Optionally, h1>(a+b), wherein h1 is the maximum depth of the first flow channel or the second flow channel or the third flow channel, a is the thickness of the substrate of the battery heat exchanger, and b is the thickness of the flow channel plate of the battery heat exchanger.

[0024] Alternatively, h1=0.5*h2, wherein h1 is the maximum depth of the first flow channel, the second flow channel, or the third flow channel, and h2 is the total thickness of the battery heat exchanger.

[0025] Optionally, the flow branching and converging structure further includes a fourth flow channel, the fourth flow channel is communicated with the first flow channel, and a flange protruding toward the flow branching and converging structure is provided between the first flow channel and the fourth flow channel.

[0026] According to a second aspect of an embodiment of the present application, there is provided a battery pack, comprising:

[0027] Battery cells;

[0028] A first battery heat exchanger and a second battery heat exchanger, wherein the first battery heat exchanger and the second battery heat exchanger are the battery heat exchangers as described in any one of the above items;

[0029] The substrate of the first battery heat exchanger contacts the first surface of the battery cell, and the substrate of the second battery heat exchanger contacts the second surface of the battery cell.

[0030] According to a third aspect of an embodiment of the present application, a vehicle is provided, wherein the vehicle is equipped with a battery heat exchanger as described in any one of the above items, or is equipped with a battery pack as described above.

[0031] The technical effect of the embodiment of the present application is that, at the position of the branch flow structure, the cross-sectional area of ​​the first flow channel is greater than the cross-sectional area of ​​the second flow channel, and the cross-sectional area of ​​the first flow channel is greater than the cross-sectional area of ​​the third flow channel. In other words, when the branch flow node is diverted, the cross-sectional area of ​​the refrigerant flowing into the first flow channel is greater than the cross-sectional area of ​​any refrigerant flowing out of the flow channel. This ensures that no matter whether the refrigerant flowing into the first flow channel is gaseous, liquid, or a gas-liquid coexisting state, after being diverted to the second flow channel and the third flow channel through the branch flow structure, no flow path will produce a sharp drop in pressure, thereby ensuring that the refrigerant can be smoothly diverted to the second flow channel and the third flow channel at the branch flow structure, and neither the second flow channel nor the third flow channel will be diverted too much due to a sharp drop in pressure, thereby improving the heat exchange performance of the entire battery heat exchanger. On the contrary, when the flow is converged at the branch and confluence junction, the cross-sectional area of ​​the refrigerant converging to the first flow channel is larger than the cross-sectional area of ​​any refrigerant flowing into the flow channel. This ensures that no matter whether the refrigerant flowing into the second flow channel or the third flow channel is gaseous, liquid, or a gas-liquid coexisting state, after converging to the first flow channel through the branch and confluence structure, the first flow channel will not produce a sharp increase in pressure, thereby ensuring that the refrigerant can be smoothly converged to the first flow channel at the branch and confluence structure, and neither the second flow channel nor the third flow channel will have excessive flow resistance due to a sharp increase in pressure, resulting in uneven convergence. Therefore, the heat exchange performance of the entire battery heat exchanger is improved.

[0032] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0034] Figure 1 An exploded diagram of a battery heat exchanger according to an embodiment of the present application;

[0035] Figure 2 A top view of a battery heat exchanger according to an embodiment of the present application;

[0036] Figure 3 For along Figure 2 A partial enlarged view of part A in FIG.

[0037] Figure 4 For along Figure 3 Cross-sectional view of line CC in;

[0038] Figure 5 For along Figure 3 A cross-sectional view of the DD line in FIG.

[0039] Figure 6 for Figure 2A partial enlarged view of part B in FIG.

[0040] Figure 7 A three-dimensional diagram of a battery pack according to an embodiment of the present application.

[0041] Explanation of the reference numerals: 1. Stud; 2. runner plate; 201. second runner; 202. third runner; 203. first chamfer; 204. flow branching structure; 205. second chamfer; 206. flange; 207. first runner; 208. fourth runner; 209. runner; 210. fake runner; 3. substrate; 4. inlet and outlet assembly; 100. first battery heat exchanger; 200. second battery heat exchanger; 300. battery cell. DETAILED DESCRIPTION

[0042] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0043] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0044] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0045] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0046] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0047] like Figures 1 to 6 As shown, the battery heat exchanger in the embodiment of the present application includes: a flow channel plate 2 and a substrate 3. In more detail, the flow channel plate 2 is formed with a flow channel groove by, for example, a stamping process, and the substrate 3 is welded to the flow channel plate 2 so that the flow channel groove is formed as shown in FIG. Figure 6 A plurality of flow channels 209 are shown.

[0048] A boss with a height equal to the plate thickness b of the flow channel plate 2 is set at the lower end of the stud 1 for brazing positioning. The bottom of the boss is brazed together with the base plate 3 and can be used to fix heat sink components such as the bottom sealing plate of the battery.

[0049] The inlet and outlet assembly 4 is used for the refrigerant fluid to enter and exit the battery heat exchanger.

[0050] The flow channel plate 2 can be formed by molding or blowing, and has the advantages of fast molding and light weight.

[0051] The flow channel plate 2 is punched at the welding position of the stud 1, and the hole diameter is the same as the boss diameter of the stud 1, which is used for welding positioning of the stud 1.

[0052] The substrate 3 is used to directly or indirectly contact the battery cell for heat exchange, and can ensure sufficient flatness. The connection between the substrate 3 and the inlet and outlet assembly 4 needs to be punched for welding and positioning of the inlet and outlet assembly 4. The flow channel plate 2 and the substrate 3 can be formed by welding to form an internal flow channel for the refrigerant fluid. The inlet and outlet assembly 4 can be welded to the substrate 3 by a brazing process.

[0053] like Figure 2 As shown, for the battery heat exchanger, the flow channel distribution area is the heating area of ​​the battery cell that needs to be cooled. The number of flow channel distribution strips N of the battery heat exchanger can be calculated based on the width L of the heating area and the flow channel density ρ. Figure 3 As shown, the flow channel density Where s1 is the minimum distance between adjacent flow channels, and s2 will be described below. The values ​​of each value in the battery heat exchanger must meet the heat dissipation requirements as well as the pressure resistance requirements and welding quality requirements of the battery heat exchanger.

[0054] like Figure 3 As shown, the battery heat exchanger includes a branch and confluence structure 204, and the branch and confluence structure 204 includes a first flow channel 207, a second flow channel 201 and a third flow channel 202. The first flow channel 207 is connected to the first interface of the battery heat exchanger, and the second flow channel 201 and the third flow channel 202 are connected to the second interface of the battery heat exchanger. More specifically, when the branch and confluence flow structure 204 is used for flow diversion, the fluid in the first flow channel 207 is diverted to the second flow channel 201 and the third flow channel 202. At this time, the first flow channel 207 is directly or indirectly connected to the first interface, which refers to the fluid inlet, while the second flow channel 201 and the third flow channel 202 are directly or indirectly connected to the second interface of the battery heat exchanger, which refers to the fluid outlet; when the branch and confluence flow structure 204 is used for flow confluence, the fluid in the second flow channel 201 and the third flow channel 202 converge into the first flow channel 207. At this time, the first flow channel 207 is directly or indirectly connected to the first interface, which serves as the fluid outlet, while the second flow channel 201 and the third flow channel 202 are directly or indirectly connected to the second interface of the battery heat exchanger, which refers to the fluid inlet. In other words, the first interface and the second interface refer to different concepts according to the different roles played by the branch and confluence flow structure 204. In fact, as Figure 2As shown, in the refrigerant fluid flow path of the entire battery heat exchanger, part of the flow dividing and converging structures 204 is used for flow dividing, and part of the flow dividing and converging structures 204 is used for flow converging.

[0055] like Figure 4 As shown, this figure only shows the cross-sections of the second flow channel 201 and the third flow channel 202, wherein the cross-sectional area of ​​the second flow channel 201 is marked as A2, and the cross-sectional area of ​​the third flow channel is marked as A3. Figure 5 As shown, the cross section of the first flow channel 207 can have a similar shape to the second flow channel 201 and the second flow channel 203, but the specific size is different, and the cross-sectional area of ​​the first flow channel 207 is marked as A1. Among them, the cross-sectional area A1 of the first flow channel 207 is greater than the cross-sectional area A2 of the second flow channel 201, and the cross-sectional area A1 of the first flow channel 207 is greater than the cross-sectional area A3 of the third flow channel 202; in other words, the cross-sectional area A1 of the first flow channel 207 is the largest among the three flow channels of the flow dividing and converging structure 204. In this article, A1, A2 and A3 all refer to the area surrounded by the inner surface of the first flow channel 207, the second flow channel 201 and the third flow channel 202, which is also the cross-sectional area that allows the fluid to pass through, and does not include the cross-sectional area of ​​the substrate 3 and the flow channel plate 2. When the flow is diverted at the branching structure 204, the cross-sectional area of ​​the refrigerant flowing into the first flow channel 207 is larger than the cross-sectional area of ​​any refrigerant outflow flow channel. This ensures that no matter whether the refrigerant flowing into the first flow channel 207 is in gaseous, liquid, or a gas-liquid coexisting state, after being diverted to the second flow channel 201 and the third flow channel 202 through the branching structure 204, no flow path will produce a sharp drop in pressure, thereby ensuring that the refrigerant can be smoothly diverted to the second flow channel 201 and the third flow channel 202 at the branching structure 204, and neither the second flow channel 201 nor the third flow channel 202 will be diverted too much due to a sharp drop in pressure, thereby improving the heat exchange performance of the entire battery heat exchanger. On the contrary, when the flow is converged at the branch and confluence junction, the cross-sectional area of ​​the refrigerant converging to the first flow channel 207 is larger than the cross-sectional area of ​​any refrigerant inflow channel. This ensures that no matter whether the refrigerant flowing into the second flow channel 201 or the third flow channel 202 is gaseous, liquid, or a gas-liquid coexistence state, after converging to the first flow channel 207 through the branch and confluence structure 204, the first flow channel 207 will not produce a sharp increase in pressure, thereby ensuring that the refrigerant can be smoothly converged to the first flow channel 207 at the branch and confluence structure 204, and will not cause any of the second flow channel 201 and the third flow channel 202 to have excessive flow resistance due to a sharp increase in pressure, resulting in uneven convergence, thereby improving the heat exchange performance of the entire battery heat exchanger.

[0056] like Figure 3As shown in FIG. 1 , the shape of each flow channel observed from the outside is shown. When the cross-sectional areas of the first flow channel 207, the second flow channel 201 and the third flow channel 202 meet the above conditions, the maximum width s5 of the outer surface of the first flow channel 207, the maximum width s3 of the outer surface of the second flow channel 201 and the maximum width s4 of the outer surface of the third flow channel 202 can adopt the same or different values ​​as shown in Table 1. s3, s4 and s5 include the thickness of the flow channel plate 2 constituting the flow channel.

[0057] As mentioned above, the cross-sectional shapes of the first flow channel 207, the second flow channel 201 and the third flow channel 202 can be similar, so for simplicity, Figure 4 In the figure, the maximum width of the first flow channel 207, the maximum width of the second flow channel 201, and the maximum width of the third flow channel 202 are uniformly referred to as the maximum width s2. s2 can be the maximum width of the inner surface of the first flow channel 207, the maximum width of the inner surface of the second flow channel 201, and the maximum width of the inner surface of the third flow channel 202, or the maximum width of the outer surface of the first flow channel 207, the maximum width of the outer surface of the second flow channel 201, and the maximum width of the outer surface of the third flow channel 202. The specific values ​​of s2 of the first flow channel 207, the second flow channel 201, and the third flow channel 202 can be the same or different.

[0058] like Figure 4 As shown, h1 is the maximum depth of the first flow channel 207 or the second flow channel 201 or the third flow channel 202, a is the thickness of the substrate 3 of the battery heat exchanger, b is the thickness of the flow channel plate 2 of the battery heat exchanger, h2 is the total thickness of the battery heat exchanger (excluding the height of the stud 1 and the inlet and outlet assembly 4), r1 is the radius of the first chamfer 203 of the first flow channel 207 or the second flow channel 201 or the third flow channel 202 away from the substrate 3 of the battery heat exchanger, r2 is the radius of the second chamfer 205 of the first flow channel 207 or the second flow channel 201 or the third flow channel 202 close to the substrate 3 of the battery heat exchanger, s1 is the minimum distance between the second flow channel groove 201 and the third flow channel groove 202, and s2 is the maximum width of the first flow channel 207 or the second flow channel 201 or the third flow channel 202. For simplicity, Figure 4 These parameters are partially marked on the second flow channel 201 or the second flow channel 202. The inventors found that these parameters affect each other, which will eventually affect the pressure resistance performance, welding reliability, etc. of the entire battery heat exchanger.

[0059] Since each flow channel is formed by processing the flow channel plate 2, the larger h1 is, the greater the thinning rate of the flow channel plate 2 is, and the lower the pressure resistance is. However, at the same time, when the cross-sectional area remains unchanged, a larger s1 can be reserved, thereby obtaining a larger welding width and improving welding reliability. Therefore, an optimal balance needs to be achieved between pressure resistance and welding reliability. The inventors found that when h1 / b∈[1 / 3, 10], that is, when the value range of h1 / b is between 1 / 3 (inclusive) and 10 (inclusive), a good balance between pressure resistance and welding reliability can be achieved.

[0060] Under the condition that the cross-sectional area of ​​the flow channel remains unchanged, the shape of the cross section is related to h1 and s2, and the shape of the cross section will affect the flow resistance of the flow channel, and the value of s2 will also affect the value of s1, thereby affecting the welding reliability, and h1 will affect the thinning rate and thus the pressure resistance. The inventors found that when h1 / s2∈[1 / 20,1], that is, when the value range of h1 / s2 is between 1 / 20 (inclusive) and 1 (inclusive), the flow resistance of the flow channel and the welding reliability can achieve a good balance.

[0061] Similarly, under the condition that the cross-sectional area of ​​the flow channel remains unchanged, the shape of the cross section is also related to h1 and r2, and the shape of the cross section will affect the flow resistance of the flow channel, and the value of h1 will also affect the thinning rate, and thus affect the pressure resistance. The inventors found that when h1 / r2∈[1 / 7,5 / 2], that is, when the value range of h1 / r2 is between 1 / 7 (inclusive) and 5 / 2 (inclusive), the flow resistance and pressure resistance of the flow channel can achieve a good balance.

[0062] The inventors further discovered that when the three conditions h1 / b∈[1 / 3, 10], h1 / s2∈[1 / 20, 1], and h1 / r2∈[1 / 7, 5 / 2] are met at the same time, the flow resistance, pressure resistance, and welding reliability of the battery heat exchanger can all be well balanced.

[0063] The inventors found that when h1 / b∈[1 / 3,5 / 1], h1 / s2∈[1 / 15,1 / 3], and h1 / r2∈[1 / 7,2 / 5] meet these three conditions, the flow resistance, pressure resistance, and welding reliability of the battery heat exchanger reach the optimal state. The above numerical combination can reduce the thinning rate of the battery heat exchanger while ensuring the pressure resistance of the battery heat exchanger. The battery heat exchanger can meet the refrigerant pressure requirements for battery heat exchange and reduce the mass of the battery heat exchanger.

[0064] The thickness a of the substrate 3 cannot be too thin, otherwise it will affect the pressure resistance of the battery heat exchanger. At the same time, it cannot be too thick, otherwise it will cause material waste, and the pressure resistance is also related to s2. The inventor found that when a / s2≥0.05, the pressure resistance brought by the thickness of the substrate 3 will be significantly improved. Of course, a / s2 cannot be infinitely large, and the maximum should not exceed 0.6, otherwise it will cause material waste. a / s2≥0.05 facilitates the stamping of the flow channel plate 2, and at the same time enables the battery heat exchanger to meet the refrigerant pressure requirements required for battery heat exchange.

[0065] like Figure 3 As shown, the ratio of the maximum width of the second flow channel 201 and the third flow channel 202 will affect the flow divergence effect. If the ratio is too small or too large, it will cause the two flow channels to have too much fluid in one flow channel and too little fluid in the other flow channel due to uneven flow resistance, which will damage the temperature uniformity of the entire battery heat exchanger. The inventors found that when s3 / s4∈[5 / 20,4], that is, the maximum width ratio of the two flow channels is between 5 / 20 (inclusive) and 4 (inclusive), the temperature uniformity of the battery heat exchanger can be guaranteed.

[0066] More preferably, s3 / s4∈[1 / 3,3 / 1], so that the flow resistance of the refrigerant in the two flow channels is closer.

[0067] like Figure 3 and Figure 6 As shown, s5 is the maximum width of the outer surface of the first flow channel, and s6 is the minimum distance between any flow channel and the surrounding structure. The surrounding structure can be an adjacent flow channel or, for example, Figure 6 The stud 1 or the false flow channel 210 in the battery heat exchanger. s6 directly affects the welding quality and the pressure resistance of the battery heat exchanger. If s6 is too small, the pressure in the flow channel will easily cause the weld to fail, causing the second flow channel 201 to be connected to the third flow channel 202, causing cracks between the flow channel and the surrounding structure, and losing the refrigerant diversion function. If s6 is too large, it will easily lead to welding quality defects, such as inability to exhaust, etc., thereby affecting the overall performance of the battery heat exchanger. This embodiment is designed to be 3mm≤s6≤45mm, thereby achieving a balance between pressure resistance and welding quality. The size of s5 affects both the cross-sectional shape of the flow channel and the welding quality and pressure resistance. Therefore, 5mm≤s5≤15mm is preferred, at which time the welding quality and pressure resistance can be balanced. s3 / s4∈[1 / 3,3 / 1], 5mm≤s5≤15mm, 3mm≤s6≤45mm. This parameter combination can meet the welding performance of the battery heat exchanger and ensure that no welding bubbles remain. It also ensures that the pressure resistance of the battery heat exchanger meets the requirements while ensuring that the processing of the battery heat exchanger is feasible.

[0068] like Figure 4As shown, the radii r1 and r2 affect the thinning rate of the flow channel plate 2, and also affect the specific shape of the flow channel cross section. r1≤r2 means that the flow channel is smoother near the substrate 3 and sharper away from the substrate 3, which can avoid pressure concentration at the joint between the substrate 3 and the flow channel plate 2 to cause welding failure.

[0069] Both r1 and h1 affect the thinning rate of the flow channel plate 2 at the flow channel. However, if r1 is too large, in order to achieve the appropriate stamping depth h1, a sharp corner will be formed on the bottom surface of the flow channel, resulting in pressure concentration at the sharp corner, and it is easy to break due to scratches during the actual use of the battery heat exchanger. Therefore, r1≤h1 is preferably used to ensure that the thinning rate can meet the pressure resistance requirements while making the bottom surface of the flow channel away from the bottom plate 3 smoother and avoiding sharp corners.

[0070] Optionally, the cross-sectional area of ​​the second flow channel 201 is equal to the cross-sectional area of ​​the third flow channel 202. The advantage of this structure is that the difference in cross-sectional area between the second flow channel 201 and the third flow channel 202 will not cause uneven flow of the refrigerant, thereby enabling the battery heat exchanger to obtain good temperature uniformity.

[0071] like Figure 4 As shown, taking the third flow channel 202 as an example, the third flow channel groove 202 has a first chamfer 203 away from the substrate 3 and a second chamfer 205 close to the substrate 3, and the radius r1 of the first chamfer 203 is smaller than the radius r2 of the second chamfer 205. The shapes of other flow channels can be the same as the third flow channel groove 202, so they are not described in detail. In the process of stamping the flow channel groove, if r1 is the same as r2 or even exceeds r2, it will lead to the inability to punch out the flow channel groove in the process, so r1≤r2. The radii r1 and r2 will affect the thinning rate of the flow channel plate 2. The smaller r1 and r2 are, the greater the thinning rate is, and the lower the pressure resistance of the battery heat exchanger is. Therefore, it is preferred that r1 is less than the flow channel depth h1 to avoid insufficient pressure resistance. At the same time, the stamping forming of the flow channel groove can also be achieved through the stamping process.

[0072] Optionally, the thickness a of the flow channel plate 2 is equal to the thickness b of the substrate 3. Therefore, selecting a=b achieves a balance between pressure resistance and heat dissipation, so that the substrate 3 or the flow channel plate 2 will not have too high pressure resistance relative to the other.

[0073] Optionally, the maximum depth h1 of the flow channel is greater than the sum of the thickness b of the substrate 3 and the thickness a of the flow channel plate 2, that is, h1>(a+b). In this way, under the same cross-sectional area of ​​the refrigerant flow channel, the width s1 between the second flow channel 201 and the third flow channel 202 can be increased as much as possible, thereby avoiding the second flow channel 201 and the third flow channel groove 202 from being connected due to insufficient pressure resistance of the battery heat exchanger. When h1 / (a+b)∈[3 / 2.8,2], the thinning rate and pressure resistance are met at the same time. Correspondingly, s1∈[4,15], the welding quality requirements can also be met.

[0074] Optionally, the depth h1 of the flow channel groove is equal to half of the total thickness h2 of the battery heat exchanger. Figure 4 As shown, the total thickness of the battery heat exchanger is the distance between the upper surface of the substrate 3 and the lower surface of the second flow channel 201 or the third flow channel groove 202. The advantage of this structure is that although the flow channel plate 2 is stamped and thinned at the flow channel, this depth limitation can still ensure that the battery heat exchanger can obtain good pressure resistance, and at the same time, the value of s1 can meet the requirements.

[0075] like Figure 3 As shown, the figure shows two branch and confluence flow structures 204, wherein the branch and confluence flow structure 204 on the right side also includes a fourth flow channel 208, and the fourth flow channel 208 is connected to the first flow channel 207. Among them, the fourth flow channel 208 is connected to the first flow channel 207 in the branch and confluence flow structure 204 on the left side, thereby making the two branch and confluence flow structures 204 connected in parallel. There is a flange 206 protruding toward the branch and confluence flow structure 204 between the first flow channel 207 and the fourth flow channel 208. The function of the flange 206 is, on the one hand, to make part of the refrigerant in the first flow channel 207 flow into the branch and confluence flow structure 204, and part of it flow toward the fourth flow channel 208 and enter the next branch and confluence flow structure 204, and on the other hand, it can also improve the welding quality. When the branch and confluence flow structure 204 is used as a confluence, the flange 206 can ensure a smooth confluence, and the principle is exactly the opposite of the diversion.

[0076] As shown in Table 1, if only one factor is considered, taking an exemplary battery heat exchanger design as an example, Figures 1 to 6 The value ranges and beneficial effects of the various parameters shown are shown in the columns of the table.

[0077] Table 1

[0078]

[0079] However, in the embodiment of the present application, since multiple factors such as heat dissipation performance, pressure resistance and welding quality are taken into consideration, the above-mentioned restrictions are added, so the parameters finally selected are:

[0080] s1=8mm; s2=13mm; h1=3mm; a=1.4mm; b=1.4mm; h2=6mm; r1=2.8mm;

[0081] r2 = 4 mm; ρ = 7 mm; s3 = 11 mm; s4 = 11 mm; s5 = 12 mm; s6 = 10 mm. In other words, the embodiment of the present application can achieve the optimal performance of the battery heat exchanger.

[0082] like Figure 7 As shown, according to a second aspect of an embodiment of the present application, a battery pack is provided, including:

[0083] Battery cell 300;

[0084] A first battery heat exchanger 100 and a second battery heat exchanger 200, wherein the first battery heat exchanger 100 and the second battery heat exchanger 200 are the battery heat exchangers as described in any of the preceding items;

[0085] The substrate 3 of the first battery heat exchanger 100 contacts the first surface of the battery cell 300, and the substrate 3 of the second battery heat exchanger 200 contacts the second surface of the battery cell 300. Figure 7 In the figure, the first surface and the second surface are the upper surface and the lower surface respectively. Compared with the harmonica cold plate, the large-area stamped battery heat exchanger reduces the temperature equalizing plate between the harmonica tube and the battery cell 300. The substrate 3 plays the role of the temperature equalizing plate. One side of the substrate 3 is in direct contact with the refrigerant, and the other side is in contact with the battery cell 300 through the heat-conducting structural adhesive. The heat generated by the battery cell 300 is directly transferred to the refrigerant through the substrate 3 and taken out of the battery pack, which greatly improves the heat transfer efficiency of the battery heat exchanger, thereby significantly improving the heat dissipation effect of the battery pack. The battery heat exchanger itself can also play the role of the battery pack cover, making the structure simpler and the cost lower.

[0086] According to a third aspect of an embodiment of the present application, a vehicle is provided, wherein the vehicle is equipped with a battery heat exchanger as described in any one of the above items, or is equipped with a battery pack as described in the above items.

[0087] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A battery heat exchanger, characterized in that: The battery heat exchanger comprises a flow dividing and converging structure (204), wherein the flow dividing and converging structure (204) comprises a first flow channel (207), a second flow channel (201) and a third flow channel (202); The cross-sectional area (A1) of the first flow channel (207) is greater than the cross-sectional area (A2) of the second flow channel (201), and the cross-sectional area (A1) of the first flow channel (207) is greater than the cross-sectional area (A3) of the third flow channel (202); The first flow channel (207) is connected to a first interface of the battery heat exchanger, and the second flow channel (201) and the third flow channel (202) are connected to a second interface of the battery heat exchanger.

2. The battery heat exchanger according to claim 1, characterized in that: h1 / b∈[1 / 3, 10], wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), and b is the thickness of the flow channel plate (2) of the battery heat exchanger.

3. The battery heat exchanger according to claim 1, characterized in that: h1 / s2∈[1 / 20,1], wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), and s2 is the maximum width of the first flow channel (207) or the second flow channel (201) or the third flow channel (202).

4. The battery heat exchanger according to claim 1, characterized in that: h1 / r2∈[1 / 7,5 / 2], wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), and r2 is the radius of the second chamfer of the first flow channel (207) or the second flow channel (201) or the third flow channel (202) close to the substrate (3) of the battery heat exchanger.

5. The battery heat exchanger according to any one of claims 1 to 4, characterized in that: h1 / b∈[1 / 3, 10], h1 / s2∈[1 / 20, 1], h1 / r2∈[1 / 7, 5 / 2], wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), b is the thickness of the flow channel plate (2) of the battery heat exchanger, s2 is the maximum width of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), and r2 is the radius of the second chamfer of the first flow channel (207) or the second flow channel (201) or the third flow channel (202) close to the substrate (3) of the battery heat exchanger.

6. The battery heat exchanger according to any one of claims 1 to 4, characterized in that: h1 / b∈[1 / 3,5 / 1], h1 / s2∈[1 / 15,1 / 3], h1 / r2∈[1 / 7,2 / 5], wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), b is the thickness of the flow channel plate (2) of the battery heat exchanger, s2 is the maximum width of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), and r2 is the radius of the second chamfer of the first flow channel (207) or the second flow channel (201) or the third flow channel (202) close to the base plate (3) of the battery heat exchanger.

7. The battery heat exchanger according to any one of claims 1 to 4, characterized in that: a / s2≥0.05, wherein a is the thickness of the substrate (3) of the battery heat exchanger, and s2 is the maximum width of the first flow channel (207) or the second flow channel (201) or the third flow channel (202).

8. The battery heat exchanger according to claim 7, characterized in that: s3 / s4∈[5 / 20,4], wherein s3 is the maximum width of the outer surface of the second flow channel (201), and s4 is the maximum width of the outer surface of the third flow channel (202).

9. The battery heat exchanger according to claim 7, characterized in that: s3 / s4∈[1 / 3,3 / 1], wherein s3 is the maximum width of the outer surface of the second flow channel (201), and s4 is the maximum width of the outer surface of the third flow channel (202).

10. The battery heat exchanger according to claim 8 or 9, characterized in that: s5≤15mm, s6≤45mm, wherein s5 is the maximum width of the outer surface of the first flow channel (207), and s6 is the minimum distance between any flow channel and the surrounding structure.

11. The battery heat exchanger according to claim 1, characterized in that: When the flow dividing and converging structure (204) is used for flow dividing, the fluid in the first flow channel (207) is divided into the second flow channel (201) and the third flow channel (202); When the flow dividing and converging structure (204) is used for converging flow, the fluids in the second flow channel (201) and the third flow channel (202) converge into the first flow channel (207).

12. The battery heat exchanger according to claim 1, characterized in that: The cross-sectional area of ​​the second flow channel (201) is equal to the cross-sectional area of ​​the third flow channel (202).

13. The battery heat exchanger according to claim 1, characterized in that: r1≤r2, wherein r1 is the radius of a first chamfer of the first flow channel (207) or the second flow channel (201) or the third flow channel (202) away from the substrate (3) of the battery heat exchanger, and r2 is the radius of a second chamfer of the first flow channel (207) or the second flow channel (201) or the third flow channel (202) close to the substrate (3) of the battery heat exchanger.

14. The battery heat exchanger according to claim 13, characterized in that: r1≤h1, wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202).

15. The battery heat exchanger according to claim 1, characterized in that: a=b, wherein a is the thickness of the base plate (3) of the battery heat exchanger, and b is the thickness of the flow channel plate (2) of the battery heat exchanger.

16. The battery heat exchanger according to claim 1, characterized in that: h1>(a+b), wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), a is the thickness of the substrate (3) of the battery heat exchanger, and b is the thickness of the flow channel plate (2) of the battery heat exchanger.

17. The battery heat exchanger according to claim 1, characterized in that: h1=0.5*h2, wherein h1 is the maximum depth of the first flow channel (207) or the second flow channel (201) or the third flow channel (202), and h2 is the total thickness of the battery heat exchanger.

18. The battery heat exchanger according to claim 1, characterized in that: The flow branching structure (204) further comprises a fourth flow channel (208), wherein the fourth flow channel (208) is connected to the first flow channel (207), and a flange (206) protruding toward the flow branching structure (204) is provided between the first flow channel (207) and the fourth flow channel (208).

19. A battery pack, characterized in that: include: Battery cell (300); A first battery heat exchanger (100) and a second battery heat exchanger (200), wherein the first battery heat exchanger (100) and the second battery heat exchanger (200) are battery heat exchangers according to any one of claims 1 to 18; The substrate (3) of the first battery heat exchanger (100) contacts the first surface of the battery cell (300), and the substrate (3) of the second battery heat exchanger (200) contacts the second surface of the battery cell (300).

20. A vehicle, characterized in that: The vehicle is equipped with a battery heat exchanger as claimed in any one of claims 1 to 18, or is equipped with a battery pack as claimed in claim 19.

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