Heat exchange plate, battery pack, and electric device

Abstract

The present application relates to the technical field of battery, discloses a heat exchange plate, a battery pack and a power utilization device, comprising: a body, an inlet joint and an outlet joint, the inlet joint and the outlet joint are arranged at the middle part of the body along a first direction, and the inlet joint and the outlet joint are arranged at intervals along a second direction; wherein, along the first direction, the length of the body is L, along the second direction, the center distance of the inlet joint and the outlet joint is h, and 5≤L / (2×h)≤32.85 is satisfied. The inlet joint and the outlet joint are arranged at the middle part of the heat exchange plate, the area on both sides of the middle part of the body is used for heat exchange of the battery, the heat exchange for two groups of batteries is realized at the same time, only one set of inlet joint and outlet joint is needed, the number of joint used is reduced, the risk of liquid leakage is reduced, and the safety performance of the battery is improved. Moreover, by limiting the value of L / (2×h), the volume energy density of the battery pack is ensured while reducing the risk of liquid leakage of the heat exchange plate.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to heat exchange plates, battery packs, and electrical devices. Background Technology

[0002] Battery packs typically include heat exchange plates for cooling the batteries. To improve heat exchange efficiency, a design can be used where the heat exchange plate is thermally connected to the battery's periphery. However, this design results in more joint components on the heat exchange plate, increasing the risk of leakage and affecting battery safety. Summary of the Invention

[0003] This invention provides a heat exchange plate, a battery pack, and an electrical device to solve the problem that heat exchange plates in the prior art increase the risk of leakage and affect the safety of battery use.

[0004] In a first aspect, the present invention provides a heat exchange plate, comprising:

[0005] The system comprises a body, an inlet connector, and an outlet connector, wherein the inlet connector and the outlet connector are located at the middle of the body along a first direction, and are spaced apart along a second direction; wherein,

[0006] Along the first direction, the length of the body is L mm, and along the second direction, the center distance between the inlet connector and the outlet connector is h mm, satisfying 5≤L / (2×h)≤32.85.

[0007] Beneficial effects: By placing the inlet and outlet connectors in the middle of the heat exchange plate, the areas on both sides of the body at the middle position can be used for heat exchange of the batteries. Therefore, while achieving simultaneous heat exchange for two sets of batteries, only one set of inlet and outlet connectors is needed, reducing the number of connectors used, lowering the risk of leakage, and improving battery safety performance. Furthermore, by limiting the value of L / (2×h), the volumetric energy density of the battery pack is guaranteed while reducing the risk of leakage from the heat exchange plate.

[0008] Secondly, the present invention also provides a battery pack, comprising:

[0009] The battery has a first end face and a second end face that are spaced apart from each other along a second direction, and a plurality of peripheral surfaces connected between the first end face and the second end face;

[0010] The aforementioned heat exchange plate is heat-exchange connected to the peripheral surface.

[0011] Thirdly, the present invention also provides an electrical device including the aforementioned battery pack. Attached Figure Description

[0012] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in 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 the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the structure of a heat exchange plate according to an embodiment of the present invention;

[0014] Figure 2 for Figure 1 The front view of the heat exchange plate is shown.

[0015] Figure 3 for Figure 2 The diagram shows the internal structure of the heat exchange plate.

[0016] Figure 4 for Figure 3 A partially enlarged structural schematic diagram of the heat exchanger plate shown.

[0017] Figure 5 This is a schematic diagram of the structure of a battery pack according to an embodiment of the present invention;

[0018] Figure 6 for Figure 5 The front view of the battery pack shown;

[0019] Figure 7 This is a schematic diagram of the structure of a battery according to an embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures:

[0021] 1. Body; 11. Heat exchange channel; 111. Inflow channel; 1111. First channel; 112. Outflow channel; 1121. Second channel; 12. First collector; 121. Inlet channel; 122. Outlet channel; 13. Sub-plate; 131. First end; 132. Second end; 14. Second collector; 2. Inlet connector; 3. Outlet connector;

[0022] 10. Heat exchange plate; 20. Battery; 201. First end face; 202. Second end face; 203. Peripheral surface; 204. First surface; 205. Second surface; 206. Terminal assembly;

[0023] 100. Battery pack; 110. Sub-battery pack; 1101. Battery row; 120. Interval zone. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] The following is combined with Figures 1 to 7 The following describes embodiments of the present invention.

[0026] According to an embodiment of the present invention, in one aspect, such as Figures 1 to 4 As shown, a heat exchange plate 10 is provided, including: a body 1, an inlet connector 2 and an outlet connector 3. The inlet connector 2 and the outlet connector 3 are disposed at the middle position of the body 1 along a first direction, and the inlet connector 2 and the outlet connector 3 are spaced apart along a second direction. In the first direction, the length of the body 1 is L mm, and the center distance between the inlet connector 2 and the outlet connector 3 is h mm along the second direction, satisfying 5≤L / (2×h)≤32.85.

[0027] By using the heat exchange plate 10 of this embodiment, and by placing the inlet connector 2 and the outlet connector 3 in the middle position of the heat exchange plate 10, the areas on both sides of the body 1 in the middle position can be used for heat exchange of the battery 20. Therefore, while achieving heat exchange for two sets of batteries 20 simultaneously, only one set of inlet connector 2 and outlet connector 3 is required, reducing the number of connectors used, reducing the risk of leakage, and improving the safety performance of the battery 20. Furthermore, by limiting the value of L / (2×h), while reducing the risk of leakage of the heat exchange plate 10, the temperature difference of the battery in the second direction is also reduced, and the volumetric energy density of the battery pack 100 can be guaranteed.

[0028] It is worth noting that in related technologies, the heat exchange plate 10 is usually located on the bottom surface of the battery pack 100 to exchange heat with the bottom surface of the battery 20. However, the bottom surface of the battery 20 is usually not the largest surface area of ​​the battery 20, resulting in a relatively weak heat exchange capacity of the heat exchange plate 10 for the battery 20, affecting the heat exchange efficiency. Therefore, researchers considered connecting the heat exchange plate 10 to the peripheral surface 203 of the battery 20 for heat exchange to increase the heat exchange area and thus improve the heat exchange efficiency. However, in related technologies, one heat exchange plate 10 can usually only heat one battery pack 100. Therefore, multiple heat exchange plates 10 are required for multiple battery packs 100, which in turn requires multiple sets of connectors. Too many connectors increase the risk of leakage, which may cause a short circuit in the battery 20 and affect the safety of the battery 20.

[0029] In this embodiment, the two opposite sides of the middle position of the main body 1 can be used to exchange heat with a battery pack 100. Furthermore, only one set of connectors needs to be set in the middle position of the main body 1 to realize the flow of heat exchange medium, which not only improves heat exchange efficiency, but also reduces the number of connectors to reduce the risk of leakage.

[0030] Furthermore, in related technologies, the connector is typically located at the end of the heat exchange plate 10, resulting in the connector being too close to the side beam of the battery pack 20. This makes it easier for vibrations from the side beam to be transmitted to the connector, increasing the risk of leakage. However, in this embodiment, the connector is located in the middle of the heat exchange plate 10, avoiding the influence of vibrations from the side beam and further reducing the risk of leakage.

[0031] Furthermore, researchers discovered that the length L mm of the body 1 along the first direction and the center distance h mm between the inlet connector 2 and the outlet connector 3 along the second direction also affect the leakage risk of the inlet connector 2 and the outlet connector 3. Therefore, in this embodiment, the leakage risk is reduced by controlling the value relationship between L mm and h mm, while avoiding excessive battery temperature differences and avoiding affecting the space utilization of the battery pack 100.

[0032] Specifically, if the value of L / (2×h) is too large, that is, if the value of L / 2 is too large and the value of h is too small, it is easy to cause excessive stress in the middle position of the body 1, thereby increasing the risk of leakage at the inlet connector 2 and the outlet connector 3. If the value of L / (2×h) is too small, it is easy to cause the distance between the inlet connector and the outlet connector in the second direction to be too large, reducing the heat exchange between them. This results in a large temperature difference of the heat exchange medium in the flow channel connected to the inlet connector and the outlet connector, especially the temperature difference of the battery closest to the inlet connector and the outlet connector. This leads to an excessive temperature difference of the battery in the second direction, affecting the charging and discharging performance and life of the battery itself, and thus reducing the life of the entire battery pack. In addition, it is also easy to cause the length of the heat exchange plate to be too small, which reduces the space for battery arrangement, resulting in insufficient space utilization of the battery pack 100 and affecting the volumetric energy density of the battery pack 100.

[0033] Optionally, L / (2×h) can be any value from 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 31, 32, 32.85 or a value between any two values.

[0034] It is worth noting that L / 2 is the distance between the middle position of body 1 and the end position of body 1 along the first direction.

[0035] It is worth noting that the first direction is the length direction of the heat exchange plate, the second direction is the height direction of the heat exchange plate, and the third direction is the thickness direction of the heat exchange plate; the first direction, the second direction, and the third direction are set perpendicular to each other.

[0036] In one embodiment, such as Figure 3 As shown, a heat exchange channel 11 is provided inside the main body 1. The main body 1 includes a first collector 12. An inlet connector 2 and an outlet connector 3 are both disposed in the first collector 12. The first collector 12 connects the inlet connector 2 and the heat exchange channel 11, and the outlet connector 3 and the heat exchange channel 11. That is, the heat exchange medium enters the first collector 12 through the inlet connector 2, and then enters the heat exchange channel 11 from the first collector 12; after flowing through the heat exchange channel 11, the heat exchange medium re-enters the first collector 12, and then flows out from the outlet connector 3.

[0037] Furthermore, in one embodiment, such as Figure 3 As shown, the main body 1 includes two sub-plates 13, which are disposed at opposite ends of the first current collector 12 along a first direction. Each sub-plate 13 has a first end 131 close to the first current collector 12, and the first end 131 is fixedly connected to the first current collector 12.

[0038] It is understandable that, such as Figure 3 As shown, each sub-plate 13 has a heat exchange channel 11, and the two sub-plates 13 are used to exchange heat for the two sets of batteries 20 respectively.

[0039] Specifically, in one embodiment, the first end 131 is welded to the first current collector 12. With this configuration, the sub-plate 13 and the first current collector 12 are formed separately and then welded, which facilitates the processing and forming of each component and avoids the poor thickness uniformity of the sub-plate 13 during forming, which would affect the strength and surface flatness of the sub-plate 13.

[0040] In one embodiment, such as Figure 4 As shown, the first current collector 12 has a first opening at both ends along the first direction, and the first end 131 is inserted into the first opening. This arrangement can improve the connection strength between the first current collector 12 and the sub-plate 13.

[0041] Specifically, in one embodiment, such as Figure 4 As shown, along the first direction, the length of the first end 131 inserted into the first opening is a mm, satisfying 3mm≤a mm≤15mm. This setting ensures the connection strength between the first collector 12 and the sub-plate 13 while avoiding any impact on the heat exchange efficiency of the heat exchange plate 10.

[0042] It is worth noting that if the value of a mm is too small, the insertion fit size between the subplate 13 and the first current collector 12 will be too small, which will have a limited effect on improving the connection strength. If the value of a mm is too large, the size of the subplate 13 inserted into the first current collector 12 will be too large, which may affect the size of the subplate 13 used for heat exchange with the battery 20, thus affecting the heat exchange efficiency of the heat exchange plate 10.

[0043] Optionally, the value of 'a' can be any one of the following: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or a value between any two of these.

[0044] In one embodiment, such as Figure 4 As shown, along the first direction, the shortest distance from the center of the inlet connector 2 and / or the center of the outlet connector 3 to the end of the heat exchange channel 11 is b mm, satisfying 12 mm ≤ b mm ≤ 30 mm. This setting reduces the risk of leakage from the heat exchange plate while avoiding any impact on the heat exchange efficiency of the heat exchange plate 10.

[0045] It is worth noting that if the value of b mm is too large, the length of the heat exchange channel 11 may be too short, affecting the heat exchange efficiency of the heat exchange plate 10. If the value of b mm is too small, the inlet connector 2 and / or outlet connector 3 may be too close to the edge of the first collector 12, which may affect the structural strength of the first collector 12 and easily lead to leakage problems.

[0046] Optionally, b can be any value from 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, or a value between any two values.

[0047] In one embodiment, such as Figure 3 As shown, the heat exchange channel 11 includes an inflow channel 111 and an outflow channel 112 arranged and connected along the second direction. The inflow channel 111 is connected to the inlet connector 2, and the outflow channel 112 is connected to the outlet connector 3. That is, the heat exchange medium enters the first collector 12 through the inlet connector 2, and then enters the inflow channel 111 through the first collector 12; after flowing through the inflow channel 111, the heat exchange medium enters the outflow channel 112, then enters the first collector 12 again, and then flows out from the outlet connector 3.

[0048] It is worth noting that, such as Figure 3 As shown, the first collector 12 has an inlet channel 121 and an outlet channel 122. The inlet channel 121 connects the inlet connector 2 and the inflow channel 111, and the outlet channel 122 connects the outlet connector 3 of the outflow channel 112.

[0049] In one embodiment, such as Figure 3As shown, the subplate 13 has a second end 132 away from the first current collector 12. The main body 1 also includes a second current collector 14, which is connected to the second end 132 and communicates with the inflow channel 111 and the outflow channel 112. That is, the second current collector 14 connects the tail end of the inflow channel 111 and the head end of the outflow channel 112, so that the heat exchange medium flows from the inflow channel 111 to the outflow channel 112.

[0050] It is worth noting that each sub-plate 13 has a second current collector 14 at its second end 132.

[0051] Furthermore, in one embodiment, such as Figure 3 As shown, along the first direction, the width of the second current collector 14 is c mm, satisfying 5 mm ≤ c mm ≤ 10 mm. This configuration ensures the heat exchange efficiency of the heat exchange plate 10 while avoiding impacting the space utilization of the battery pack 100.

[0052] It is worth noting that if the value of c mm is too large, the heat exchange plate 10 will occupy too much space, which may affect the space utilization of the battery pack 100. If the value of c mm is too small, it may affect the flow rate of the heat exchange medium from the inflow channel 111 to the outflow channel 112, thus affecting the heat exchange efficiency of the heat exchange plate 10.

[0053] Optionally, c can take any value from 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, or a value between any two values.

[0054] In one embodiment, such as Figure 4 As shown, the inflow channel 111 includes a plurality of first flow channels 1111 arranged at intervals along a second direction, and the outflow channel 112 includes a plurality of second flow channels 1121 arranged at intervals along a second direction. Each of the first flow channels 1111 is connected to the inlet connector 2, and each of the second flow channels 1121 is connected to the outlet connector 3. Specifically, each first flow channel 1111 extends along a first direction, and each second flow channel 1121 extends along a first direction.

[0055] Preferably, in one embodiment, such as Figure 4 As shown, along the second direction, the width d mm of the first flow channel 1111 and the width e mm of the second flow channel 1121 are equal. This arrangement ensures the uniformity of the heat exchange medium flowing within the first flow channel 1111 and the second flow channel 1121.

[0056] As an alternative implementation, optionally, along the second direction, the width d mm of the first flow channel 1111 and the width e mm of the second flow channel 1121 are not equal, satisfying |de|≤40. This setting avoids excessive differences in flow rate between the first flow channel 1111 and the second flow channel 1121, thus ensuring uniform heat exchange.

[0057] Optionally, |de| can take any value from 0, 5, 10, 15, 20, 25, 30, 35, 40, or a value between any two values.

[0058] Furthermore, in one embodiment, such as Figure 4 As shown, along the second direction, the width of the inflow channel 111 is f mm, and the width of the outflow channel 112 is g mm, satisfying 1 / 2 ≤ g / (f+g) ≤ 2 / 3. This setting ensures that the heat exchange medium after heat exchange through the inflow channel 111 flows out quickly, avoiding excessively high temperatures of the heat exchange medium inside the heat exchange plate 10 that could affect the heat exchange effect.

[0059] In one embodiment, such as Figure 4 As shown, along the second direction, the shortest distance from the center of the inlet connector 2 and / or the center of the outlet connector 3 to the edge of the body 1 is i mm, satisfying 5 mm ≤ i mm ≤ 30 mm. This setting ensures the structural strength of the first current collector 12 while avoiding excessive stress concentration between the inlet connector 2 and the outlet connector 3.

[0060] It is worth noting that if the value of i mm is too large, the distance between the inlet connector 2 and the outlet connector 3 may be too close, which may cause stress concentration between the inlet connector 2 and the outlet connector 3, leading to the risk of leakage. If the value of i mm is too small, the inlet connector 2 and / or the outlet connector 3 may be too close to the edge of the first manifold 12, affecting the structural strength of the first manifold 12 and also leading to the risk of leakage.

[0061] Optionally, the value of i can be any one of 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30 or a value between any two values.

[0062] Specifically, in one embodiment, such as Figure 2 As shown, in one embodiment, the length L mm of the body 1 satisfies 800 mm ≤ L mm ≤ 1400 mm. This configuration reduces the risk of leakage from the heat exchange plate 10 while ensuring the volumetric energy density of the battery pack 100.

[0063] It is worth noting that if the value of L mm is too large, that is, if the value of L / 2 is too large, it is easy to cause excessive stress in the middle position of the main body 1, thereby increasing the risk of leakage at the inlet connector 2 and the outlet connector 3. If the value of L mm is too small, it is easy to reduce the space for battery arrangement, thereby resulting in insufficient space utilization of the battery pack 100 and affecting the volumetric energy density of the battery pack 100.

[0064] Optionally, L can be any value from 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350, 1400, or a value between any two values.

[0065] Specifically, in one embodiment, such as Figure 2 As shown, the center distance h mm between the inlet connector 2 and the outlet connector 3 satisfies 20 mm ≤ h mm ≤ 80 mm. This setting reduces the risk of leakage from the heat exchange plate 10 while ensuring the volumetric energy density of the battery pack 100.

[0066] It is worth noting that if the value of h mm is too large, the distance between the inlet and outlet connectors in the second direction may become too great, reducing heat exchange between them. This results in a significant temperature difference in the heat exchange medium within the flow channels connected to the inlet and outlet connectors, especially in the batteries closest to them. This leads to an excessive temperature difference in the batteries in the second direction, affecting their charge / discharge performance and lifespan, and consequently reducing the overall lifespan of the battery pack. Furthermore, it may cause the heat exchange plate 10 to occupy too much space in the second direction, impacting the space utilization of the battery pack 100. If the value of h mm is too small, the distance between the inlet connector 2 and outlet connector 3 may become too close, potentially causing stress concentration between them and increasing the risk of leakage.

[0067] Optionally, h can be any value from 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, or a value between any two values.

[0068] According to an embodiment of the present invention, on the other hand, such as Figures 5 to 7 As shown, a battery pack 100 is also provided, including: a battery 20 having a first end face 201 and a second end face 202 disposed at a distance from each other along a second direction, and a plurality of peripheral surfaces 203 connected between the first end face 201 and the second end face 202; the aforementioned heat exchange plate 10 is heat-exchange connected to the peripheral surfaces 203.

[0069] It is worth noting that the first end face 201 and the second end face 202 refer to the top and bottom surfaces of the battery 20, and the multiple peripheral surfaces 203 refer to the multiple side surfaces arranged around the battery. The peripheral surfaces 203, the first end face 201, and the second end face 202 are all vertically arranged. For example, for a prismatic battery 20, there are four peripheral surfaces 203.

[0070] In one embodiment, such as Figure 5 As shown, the battery pack 100 includes two sub-battery packs 110 spaced apart along a first direction to form a gap region 120 between the two sub-battery packs 110. The inlet connector 2 and the outlet connector 3 are both located in the gap region 120. Specifically, the two sub-plates 13 are respectively heat-exchange connected to the two sub-battery packs 110.

[0071] Furthermore, in one embodiment, such as Figure 3 and Figure 6 As shown, along the first direction, the width of the interval 120 is j mm, and the diameter of the inlet connector 2 and / or outlet connector 3 is k mm, satisfying 5 ≤ jk ≤ 30. This arrangement reduces the risk of leakage from the heat exchange plate 10 while ensuring the space utilization rate of the battery pack 100.

[0072] It is worth noting that if the value of jk is too large, the space occupied by the interval zone 120 may be too large, affecting the layout space of the battery pack 100 and reducing the space utilization rate of the battery pack 100. If the value of jk is too small, the inlet connector 2 and / or outlet connector 3 may be too close to the battery pack 100, which may cause the battery pack 100 to squeeze the inlet connector 2 and / or outlet connector 3, resulting in breakage and leakage.

[0073] Optionally, jk can take any value from 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30 or a value between any two values.

[0074] Specifically, in one embodiment, the width j mm of the interval 120 satisfies 20 mm ≤ j mm ≤ 50 mm.

[0075] Optionally, j can take any value from 20, 22, 25, 28, 30, 32, 35, 38, 40, 42, 45, 48, 50, or a value between any two values.

[0076] Specifically, in one embodiment, the diameter k mm of the inlet connector 2 and / or the outlet connector 3 satisfies 10 mm ≤ k mm ≤ 20 mm.

[0077] Optionally, k can take any value from 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or a value between any two values.

[0078] In one embodiment, such as Figure 7 As shown, the multiple peripheral surfaces 203 include two first surfaces 204 and two second surfaces 205 arranged opposite to each other. The area of ​​the first surface 204 is larger than the area of ​​the second surface 205. The heat exchange plate 10 is heat-exchange connected to the first surface 204. That is, the first surface 204 is the larger surface of the battery 20, so that the heat exchange plate 10 is heat-exchange connected to the larger surface of the battery 20, thereby improving the heat exchange efficiency.

[0079] It is worth noting that the area of ​​the first surface 204 is not only larger than the area of ​​the second surface 205, but is also usually larger than the area of ​​the first end surface 201 and the second end surface 202. That is, the first surface 204 is the surface with the largest area among all the surfaces of the battery 20.

[0080] Furthermore, in one embodiment, the length L mm of the body 1 satisfies 800 mm ≤ L mm ≤ 1350 mm.

[0081] It is worth noting that the battery 20 expands more significantly, exerting greater pressure on the heat exchange plate 10. Therefore, the length L mm of the body 1 needs to be further controlled to avoid excessive stress in the middle of the heat exchange plate 10, which could lead to leakage.

[0082] Of course, in other alternative implementations, the heat exchange plate 10 can also be connected to the second surface 205 (not the large surface) for heat exchange. The specific arrangement can be determined according to actual needs.

[0083] In one embodiment, such as Figure 7 As shown, the battery 20 includes a terminal assembly 206, which is disposed on the first end face 201. The inlet connector 2 is disposed closer to the first end face 201 than the outlet connector 3.

[0084] It is worth noting that the terminal assembly 206, as the output terminal of the current, generates more heat when the battery 20 is running. Therefore, bringing the heat exchange medium closer to the terminal assembly 206 improves the cooling effect at the terminal assembly 206 and thus enhances the safety of the battery 20 during operation.

[0085] In one embodiment, the heat exchange plate 10 and the peripheral surface 203 are fixedly connected. When L mm ≥ 1000 mm, the ratio of the projected area of ​​the orthographic projection of the peripheral surface 203 to the projected area of ​​the orthographic projection of the body 1 on the projection plane perpendicular to the third direction is not less than 60%.

[0086] It is worth noting that when the value of L mm is large, it is easy to cause excessive stress concentration in the middle position of the heat exchange plate 10. Therefore, increasing the fixed connection area between the peripheral surface 203 and the heat exchange plate 10 can improve the structural strength and stability of the heat exchange plate 10 and reduce the risk of leakage.

[0087] Specifically, the heat exchange plate 10 can be bonded and fixed to the peripheral surface 203 using thermally conductive structural adhesive.

[0088] In one embodiment, such as Figure 5 and Figure 7 As shown, the plurality of peripheral surfaces 203 include two first surfaces 204 arranged at relative intervals along a third direction, and both first surfaces 204 are heat exchangedly connected to heat exchange plates 10. That is, heat exchange plates 10 are provided on two opposite surfaces of the battery 20 along a third direction, thereby improving heat exchange efficiency.

[0089] Specifically, in this embodiment, such as Figure 5 As shown, each sub-battery pack 110 includes several rows of battery rows 1101 arranged at intervals along a third direction of the battery 20. Each row of battery rows 1101 includes one battery 20 or several batteries 20 arranged at intervals along a first direction. A sub-plate 13 is provided between adjacent battery rows 1101. Therefore, several heat exchange plates 10 are arranged at intervals along a third direction. Furthermore, the battery pack 100 also includes an inlet pipe and an outlet pipe. The inlet pipe is connected to the inlet connector 2 of several heat exchange plates 10, and the outlet pipe is connected to the outlet connector 3 of several heat exchange plates 10.

[0090] It is worth noting that measuring instruments such as micrometers or calipers are used to measure parameters such as length, width, distance, and thickness, and the area is calculated using these parameters.

[0091] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0092] The preparation of the example battery and the comparative battery includes the following steps:

[0093] (1) Preparation of the positive electrode:

[0094] The prepared positive electrode active material, conductive agent acetylene black, and binder PVDF are mixed, and solvent NMP is added. The mixture is stirred under vacuum until the system is homogeneous to obtain a positive electrode slurry. The positive electrode slurry is uniformly coated on both surfaces of the positive electrode current collector aluminum foil, air-dried at room temperature, and then transferred to an oven for further drying. Finally, it is cold-pressed and slit to obtain the positive electrode sheet. Specifically, the mass ratio of positive electrode active material: conductive agent: binder satisfies (92~98):(4~1):(4~1).

[0095] (2) Preparation of negative electrode:

[0096] The negative electrode active material, conductive agent acetylene black, thickener CMC, and binder SBR are mixed, and deionized water is added as a solvent. The mixture is stirred under vacuum until the system is homogeneous to obtain a negative electrode slurry. The negative electrode slurry is uniformly coated on both surfaces of the negative electrode current collector copper foil, air-dried at room temperature, and then transferred to an oven for further drying. After cold pressing and slitting, the negative electrode sheet is obtained. The ratio of negative electrode active material: conductive agent: thickener: binder satisfies (90~96): (4~2): (2~1): (4~1).

[0097] (3) Preparation of electrolyte:

[0098] Ethylene carbonate (EC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) were mixed in a volume ratio of 1:1:1 to obtain an organic solvent. Then, fully dried lithium salt LiPF6 was dissolved in the mixed organic solvent to prepare an electrolyte with a concentration of 1 mol / L.

[0099] (4) Preparation of the diaphragm:

[0100] Polyethylene film is selected as the diaphragm.

[0101] (5) Preparation of lithium-ion batteries:

[0102] The above-mentioned positive electrode sheet, separator, and negative electrode sheet are stacked in sequence and wound or stacked to form a bare battery cell. The bare cell is placed in a battery casing, which is a square casing. The battery is dried, injected with electrolyte, and then packaged, left to stand, formed, and volume-adjusted to obtain a lithium-ion battery.

[0103] The positive electrode active material can be selected from one or more lithium-containing positive electrode active materials, including lithium iron phosphate, ternary materials containing nickel, cobalt, and manganese, and lithium manganese iron phosphate; the negative electrode active material can be selected from one or more negative electrode active main materials, such as artificial graphite, natural graphite, silicon carbide, silicon oxide, and lithium titanate.

[0104] The difference between the batteries in each embodiment and the comparative battery lies in the values ​​of L / 2 and h, as shown in Table 1.

[0105] The relevant performance of the batteries in the above embodiments and comparative examples was tested, and the test results are recorded in Table 1. The test methods are as follows:

[0106] Performance 1: Heat exchanger plate leakage

[0107] The test subject was a battery pack. For each embodiment and comparative example, 200 square-shell batteries were combined with a heat exchange plate and installed in the battery pack housing. After installation, the housing cover was closed and secured, and a heat exchange medium, namely ethylene glycol aqueous solution, was introduced into the heat exchange plate. All other test conditions were the same.

[0108] According to GB / T2423.43, the test object was mounted on a vibration table. The test procedure was carried out according to GB / T2423.56. Random and fixed-frequency vibration loads were applied in each direction, and the loading sequence should preferably be random z-axis, fixed-frequency z-axis, random y-axis, fixed-frequency y-axis, random x-axis, fixed-frequency x-axis (the direction of the line connecting the front and rear of the battery pack is the x-axis direction, and the other horizontal direction perpendicular to the x-axis direction is the y-axis direction). The vibration frequency, power spectral density (PSD), vibration time, etc. are shown in Table 2.

[0109] After the test, remove the battery pack cover and check if the heat exchange plate is leaking.

[0110] Performance 2: Maximum temperature difference of the battery in the second direction

[0111] The test subject was a battery pack. For each embodiment and comparative example, 200 square-shell batteries were combined with a heat exchange plate. Temperature sensors (NTCs) were installed on the top and bottom surfaces of the 10 batteries closest to the inlet and outlet connectors, respectively. The NTCs were connected to a data acquisition device to record the top temperature T1 and bottom temperature T2 of the batteries in real time. The heat exchange plate and batteries were installed in the battery pack housing. After installation, the housing cover was closed and secured, and a heat exchange medium, using an aqueous solution of ethylene glycol, was introduced into the heat exchange plate. All other test conditions were the same.

[0112] The prepared battery pack was placed at room temperature (20℃) until thermal equilibrium was reached. It was then charged at a constant current rate of 4C until the battery pack voltage reached its upper limit. Subsequently, constant voltage charging was switched until the battery pack current dropped to 0.05C. The top and bottom temperatures of the 10 batteries in the battery pack were recorded throughout the charging process. The temperature difference between the two ends of a single battery was ΔT = |T1 - T2|. The largest ΔT value among the 10 batteries was taken as the maximum temperature difference between the upper and lower parts (in the second direction) of the battery pack. If the maximum temperature difference between the upper and lower parts of the battery is less than or equal to 3℃, it is considered good; if the maximum temperature difference is greater than 3℃ but less than or equal to 5℃, it is considered acceptable; if the maximum temperature difference is greater than 5℃, it is considered unacceptable.

[0113] Table 1:

[0114]

[0115] Table 2:

[0116]

[0117] As can be seen from Table 1, in Examples 1 to 12, the value of L / (2×h) is in the range of 5 to 32.85. Therefore, in Examples 1 to 12, no leakage occurred in the heat exchange plate, and the maximum temperature difference between the upper and lower parts of the battery did not fail to meet the requirements.

[0118] As can be seen from Table 1, in Comparative Example 1, the value of L / (2×h) is not in the range of 5 to 32.85 and is less than 5. Therefore, in Comparative Example 1, the maximum temperature difference test of the upper and lower parts of the battery is unqualified.

[0119] As can be seen from Table 1, in Comparative Example 2, the value of L / (2×h) is not in the range of 5 to 32.85 and is greater than 32.85. Therefore, in Comparative Example 2, the heat exchange plate has a leakage problem.

[0120] According to an embodiment of the present invention, in another aspect, an electrical device is also provided, including the battery pack 100 described above.

[0121] The following defines and explains some of the terms used in this application.

[0122] Battery packs can serve as the operating power source for electrical devices, or as the driving power source for electrical devices, replacing or partially replacing fuel or natural gas to provide driving power for vehicles. Electrical devices include: energy storage devices, electric ships, aircraft, laptops, power tools, electric bicycles, electric motorcycles, electric cars, military equipment, aerospace, and many other technological fields.

[0123] A battery pack consists of multiple battery packs, which can be connected in series, parallel, or a combination thereof. A combination thereof means that multiple battery packs are connected in both series and parallel.

[0124] The battery pack is a cluster-level battery structure formed by multiple battery packs connected in series, with the number of battery packs in each cluster strictly configured according to voltage and capacity requirements. Specifically, the battery unit of the battery pack includes multiple batteries, some of which are connected in series to form a cluster that meets the preset power supply voltage requirements, and at least one spare battery among the multiple batteries is bypassed.

[0125] The battery pack may include: battery cells and a switching control unit.

[0126] A battery can store chemical energy and controllably convert it into electrical energy. In recyclable batteries, the active materials can be reactivated by charging after discharge, allowing for continued use. A battery consists of a casing and battery cells housed within the casing.

[0127] The terminal assembly is used to electrically connect the battery cell located inside the casing to external devices (adjacent batteries or other electrical equipment) located outside the casing. The battery can discharge to the external device through the cell output terminal (tab) and the external device output terminal (terminal assembly), and an external power source can charge the battery through the terminal assembly and the tab. The terminal assembly can be directly electrically connected to the cell tab, or it can be electrically connected to the tab through a metal adapter.

[0128] The pole assembly includes, but is not limited to, metal materials such as copper, aluminum, aluminum alloy, and copper-aluminum alloy.

[0129] The heat exchange plate is thermally connected to the battery and is used to dissipate heat from the individual battery cells in order to regulate the temperature of the individual battery cells.

[0130] A refrigerant can be installed inside the heat exchange plate to cool the battery cells. The refrigerant can be gas, solid, or liquid. Liquid refrigerants can also contain liquids with high specific heat capacity, such as water, to achieve liquid cooling of the battery cells.

[0131] The heat exchange plate can be constructed as a liquid cooling plate or a phase change cooling plate and is thermally connected to the battery.

[0132] The liquid cooling plate contains liquid cooling channels, which can have various shapes, such as linear, U-shaped, U-shaped, or S-shaped. Optionally, the liquid cooling plate also includes an inlet and an outlet, both of which are connected to the manifold for the introduction and discharge of the heat exchange medium. The liquid cooling plate can be made of a material with a certain degree of hardness and strength (such as stainless steel), making it less prone to deformation when the battery is subjected to pressure or impact, thus enabling the battery to have higher structural strength and improved safety performance. The materials used for the liquid cooling plate can be various, including but not limited to: copper, iron, aluminum, stainless steel, aluminum alloy, etc. The liquid cooling plate can also be made of nylon, plastic, etc.

[0133] The heat exchange media used in liquid cooling include, but are not limited to, aqueous solutions of ethylene glycol, aqueous solutions of propylene glycol, mineral oil, silicone oil, synthetic oil, hydrofluoroether, perfluoropolyether, and duplex fluorinated liquid.

[0134] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery pack, characterized in that, include: The battery (20) has a first end face (201) and a second end face (202) that are spaced apart from each other along a second direction, and a plurality of peripheral surfaces (203) connected between the first end face (201) and the second end face (202). A heat exchange plate (10) is heat-exchange connected to the peripheral surface (203); the plurality of peripheral surfaces (203) include two first surfaces (204) and two second surfaces (205) arranged opposite to each other, the area of ​​the first surface (204) is larger than the area of ​​the second surface (205), and the heat exchange plate (10) is heat-exchange connected to the first surface (204); The heat exchange plate (10) includes: The battery (20) comprises a body (1), an inlet connector (2), and an outlet connector (3), wherein the inlet connector (2) and the outlet connector (3) are located at the middle of the body (1) along a first direction, and the inlet connector (2) and the outlet connector (3) are spaced apart along a second direction; the battery (20) includes a terminal assembly (206), which is located on the first end face (201), and the inlet connector (2) is located closer to the first end face (201) than the outlet connector (3); wherein, The heat exchange plate (10) and the peripheral surface (203) are fixedly connected. Along the first direction, the length of the body (1) is L mm. Along the second direction, the center distance between the inlet connector (2) and the outlet connector (3) is h mm, satisfying 11.74≤L / (2×h)≤32.85, 1000mm≤L mm≤1400mm, 20mm≤h mm≤42.6mm. On the projection plane perpendicular to the third direction, the ratio of the projected area of ​​the orthographic projection of the peripheral surface (203) to the projected area of ​​the orthographic projection of the body (1) is not less than 60%.

2. The battery pack according to claim 1, characterized in that, The body (1) has a heat exchange channel (11) inside. The body (1) includes a first collector (12). The inlet connector (2) and the outlet connector (3) are both located in the first collector (12). The first collector (12) connects the inlet connector (2) and the heat exchange channel (11), as well as the outlet connector (3) and the heat exchange channel (11).

3. The battery pack according to claim 2, characterized in that, The main body (1) includes two sub-plates (13), which are disposed at opposite ends of the first current collector (12) along the first direction. The sub-plates (13) have a first end (131) close to the first current collector (12), and the first end (131) is fixedly connected to the first current collector (12).

4. The battery pack according to claim 3, characterized in that, The first end (131) is welded to the first current collector (12).

5. The battery pack according to claim 3, characterized in that, The first current collector (12) has a first opening at both ends along the first direction, and the first end (131) is inserted into the first opening.

6. The battery pack according to claim 5, characterized in that, Along the first direction, the length of the first end (131) inserted into the first opening is a mm, satisfying 3mm≤a mm≤15mm.

7. The battery pack according to claim 2, characterized in that, Along the first direction, the shortest distance from the center of the inlet connector (2) and / or the center of the outlet connector (3) to the end of the heat exchange channel (11) is b mm, satisfying 12 mm ≤ b mm ≤ 30 mm.

8. The battery pack according to claim 3, characterized in that, The heat exchange channel (11) includes an inflow channel (111) and an outflow channel (112) arranged and connected along the second direction. The inflow channel (111) is connected to the inlet connector (2), and the outflow channel (112) is connected to the outlet connector (3).

9. The battery pack according to claim 8, characterized in that, The subplate (13) has a second end (132) away from the first collector (12), and the body (1) also includes a second collector (14), which is connected to the second end (132) and communicates with the inflow channel (111) and the outflow channel (112).

10. The battery pack according to claim 9, characterized in that, Along the first direction, the width of the second current collector (14) is c mm, which satisfies 5 mm ≤ c mm ≤ 10 mm.

11. The battery pack according to claim 8, characterized in that, The inflow channel (111) includes a plurality of first flow channels (1111) arranged at intervals along the second direction, and the outflow channel (112) includes a plurality of second flow channels (1121) arranged at intervals along the second direction. The plurality of first flow channels (1111) are all connected to the inlet connector (2), and the plurality of second flow channels (1121) are all connected to the outlet connector (3).

12. The battery pack according to claim 11, characterized in that, Along the second direction, the width d mm of the first flow channel (1111) and the width e mm of the second flow channel (1121) are equal.

13. The battery pack according to claim 11, characterized in that, Along the second direction, the width d mm of the first flow channel (1111) and the width e mm of the second flow channel (1121) are not equal, satisfying |de|≤40.

14. The battery pack according to claim 8, characterized in that, Along the second direction, the width of the inflow channel (111) is f mm and the width of the outflow channel (112) is g mm, satisfying 1 / 2≤g / (f+g)≤2 / 3.

15. The battery pack according to any one of claims 1 to 14, characterized in that, Along the second direction, the shortest distance from the center of the inlet connector (2) and / or the center of the outlet connector (3) to the edge of the body (1) is imm, satisfying 5mm≤i mm≤30mm.

16. The battery pack according to claim 1, characterized in that, The battery pack (100) includes two sub-battery packs (110) spaced apart along the first direction to form a gap region (120) between the two sub-battery packs (110), and the inlet connector (2) and the outlet connector (3) are both located in the gap region (120).

17. The battery pack according to claim 16, characterized in that, Along the first direction, the width of the interval (120) is j mm, and the diameter of the inlet connector (2) and / or the outlet connector (3) is k mm, satisfying 5≤jk≤30.

18. The battery pack according to claim 1, characterized in that, The length L mm of the body (1) satisfies 800 mm ≤ L mm ≤ 1350 mm.

19. The battery pack according to claim 1, characterized in that, The plurality of peripheral surfaces (203) include two first surfaces (204) arranged at relative intervals along a third direction, and both first surfaces (204) are heat-exchange connected to the heat exchange plate (10).

20. An electrical device, characterized in that, The battery pack (100) includes any one of claims 1 to 19.

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