Heat exchange plate, battery module, battery pack and electric equipment

Abstract

The application discloses a heat exchange plate, a battery module, a battery pack and a power utilization equipment, and belongs to the battery field. The heat exchange plate comprises refrigerant and a heat exchange flow channel. The refrigerant is arranged in the heat exchange flow channel. The heat exchange flow channel comprises an ascending flow channel and a descending flow channel which are connected in series. In the case that the temperature difference of the battery cell along the height direction is greater than a temperature threshold, the ascending flow channel is used for passing the refrigerant in the evaporation process or after the evaporation process, and the descending flow channel is used for passing the refrigerant in the condensation process or after the condensation process. The ascending flow channel and the descending flow channel which are connected in series are arranged, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can be used for realizing the efficient heat exchange of the upper and lower regions of the battery cell, and the temperature difference of the whole battery module is effectively reduced.

Description

Technical Field

[0001] This application belongs to the field of battery technology, and in particular relates to a heat exchange plate, a battery module, a battery pack and an electrical device. Background Technology

[0002] To improve the user experience of new energy vehicles and reduce charging waiting time, achieving high-rate fast charging of power batteries has become an increasingly important technical challenge for the new energy vehicle industry in recent years. However, due to the large amount of heat generated by the battery cells under high-temperature and high-rate fast charging conditions, if the cells cannot be cooled efficiently in real time, they are prone to overheating and excessive temperature differences, resulting in poor safety.

[0003] Currently, due to concerns about cell thermal safety, the charging current can only be reduced, thus limiting the fast charging rate of the cells. Most current battery packs use liquid cooling plates or direct cooling plates above or below the battery module for cooling. Since the coolant or refrigerant only flows through the upper or lower side of the cell, this cooling method results in a large temperature difference between the top and bottom, with the side furthest from the cooling surface being hotter. This fails to achieve efficient cooling of the cells and needs improvement. Summary of the Invention

[0004] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes a heat exchange plate, a battery module, a battery pack, and an electrical device, which can effectively reduce the overall temperature difference of the battery module.

[0005] In a first aspect, this application provides a heat exchange plate disposed on the side of a battery cell, the heat exchange plate comprising:

[0006] refrigerant;

[0007] A heat exchange channel is provided, wherein the refrigerant is disposed within the heat exchange channel. The heat exchange channel includes an ascending channel and a descending channel that are connected end to end. When the temperature difference of the battery cell along the height direction is greater than a temperature threshold, the ascending channel is used to allow the refrigerant to pass through during or after evaporation, and the descending channel is used to allow the refrigerant to pass through during or after condensation.

[0008] According to the heat exchange plate of this application, by setting up an ascending flow channel and a descending flow channel connected end to end, when the temperature difference of the battery cell along the height direction is greater than the temperature threshold, the lower end of the heat exchange plate exchanges heat with the lower part of the battery cell and the tray. The refrigerant absorbs heat and evaporates at the lower end of the heat exchange plate, changing from a liquid phase to a gas phase. The gaseous refrigerant flows along the ascending flow channel to the upper end of the heat exchange plate under the action of buoyancy. The upper end of the heat exchange plate exchanges heat with the upper part of the battery cell and the cooler. The gaseous refrigerant liquefies upon encountering cooling and releasing heat at the upper end of the heat exchange plate. The liquid refrigerant flows along the descending flow channel to the lower end of the heat exchange plate under the action of gravity, forming a refrigerant reflux. Thus, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can achieve efficient heat exchange between the upper and lower regions of the battery cell, effectively reducing the overall temperature difference of the battery module. Compared with the scheme of setting one cooler at the top and one at the bottom along the height direction of the battery cell, the cost and weight of the battery module are reduced, and the structure is simple.

[0009] According to one embodiment of this application, the heat exchange channel is annular, and the rising channel is formed along a first direction between the lowest point and the highest point of the inner ring contour of the heat exchange channel, and the falling channel is formed along the first direction between the highest point and the lowest point of the inner ring contour of the heat exchange channel, wherein the flow rate of the rising channel is smaller than that of the falling channel.

[0010] According to one embodiment of this application, the descending flow channel includes a first flow channel, a second flow channel, and a third flow channel connected in sequence, and the ascending flow channel includes a fourth flow channel and a fifth flow channel connected in sequence.

[0011] The lower end of the first flow channel is connected to the upper end of the second flow channel, the lower end of the second flow channel is connected to the upper end of the third flow channel, the lower end of the third flow channel is connected to the lower end of the fourth flow channel, the upper end of the fourth flow channel is connected to the lower end of the fifth flow channel, and the upper end of the fifth flow channel is connected to the upper end of the first flow channel.

[0012] The upper end of the fifth flow channel is higher than the upper end of the second flow channel along the direction of gravity.

[0013] According to one embodiment of this application, the second flow channel and the fifth flow channel extend along the direction of gravity; and / or, the flow area of ​​the fifth flow channel is greater than the flow area of ​​the second flow channel.

[0014] According to one embodiment of this application, the following conditions are met: 0° < θ1 ≤ 25°, where θ1 is the inclination angle of the first flow channel relative to the horizontal direction; and / or,

[0015] Satisfying: 0°<θ2≤45°, where θ2 is the inclination angle of the third flow channel relative to the horizontal direction; and / or,

[0016] It satisfies: 0°<θ3≤45°, where θ3 is the inclination angle of the fourth flow channel relative to the horizontal direction.

[0017] According to one embodiment of this application, the flow cross-sectional area of ​​the fourth flow channel gradually increases from the end connected to the third flow channel to the end connected to the fifth flow channel; and / or,

[0018] The cross-sectional area of ​​the first flow channel gradually increases from the end connected to the fifth flow channel to the end connected to the second flow channel.

[0019] According to one embodiment of this application, the first flow channel, the second flow channel, the third flow channel, and the fourth flow channel each include two sets, and the two sets of the first flow channel, the two sets of the second flow channel, the two sets of the third flow channel, and the two sets of the fourth flow channel are symmetrically distributed on both sides of the fifth flow channel with the fifth flow channel as the axis of symmetry.

[0020] According to one embodiment of this application, the heat exchange channel further includes a sixth channel, which is disposed between the third channel and the fourth channel, and the sixth channel extends horizontally and is close to the bottom end of the heat exchange plate along the direction of gravity.

[0021] According to one embodiment of this application, the tilt angle of the fourth flow channel relative to the horizontal direction is greater than the tilt angle of the third flow channel relative to the horizontal direction.

[0022] According to one embodiment of this application, the heat exchange plate includes a first portion and a second portion, the first portion and the second portion together defining the heat exchange channel;

[0023] A first protrusion and a second protrusion are provided on the outer side of the first part and / or the outer side of the second part. The first protrusion and the second protrusion are arranged at intervals along the direction of gravity. The first protrusion and the second protrusion are used to connect with the battery cell.

[0024] According to one embodiment of this application, the first part and the second part are positioned and matched.

[0025] According to one embodiment of this application, the heat exchange plate further includes a pressure relief valve, which is connected to the heat exchange channel.

[0026] According to one embodiment of this application, the heat exchange plate is further provided with a thinning zone, which is located in the heat exchange channel.

[0027] Secondly, this application provides a battery module, including a battery cell and a heat exchange plate as described in any one of the above-mentioned methods, wherein the heat exchange plate is disposed on the side of the battery cell.

[0028] The battery module provided in this application embodiment, by setting a heat exchange plate as described in the above embodiment on the side of the battery cell, has an upward flow channel and a downward flow channel connected end to end. When the temperature difference of the battery cell along the height direction is greater than the temperature threshold, the lower end of the heat exchange plate exchanges heat with the lower part of the battery cell and the tray. The refrigerant absorbs heat and evaporates at the lower end of the heat exchange plate, changing from a liquid phase to a gas phase. The gas phase refrigerant flows along the upward flow channel to the upper end of the heat exchange plate under the action of buoyancy. The upper end of the heat exchange plate exchanges heat with the upper part of the battery cell and the cooler. The gas phase refrigerant liquefies upon encountering cooling and releasing heat at the upper end of the heat exchange plate. The liquid phase refrigerant flows along the downward flow channel to the lower end of the heat exchange plate under the action of gravity, forming a refrigerant reflux. Thus, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can achieve efficient heat exchange between the upper and lower regions of the battery cell, effectively reducing the overall temperature difference of the battery module. Compared with the scheme of setting one cooler at the top and one at the bottom along the height direction of the battery cell, the cost and weight of the battery module are reduced, and the structure is simple.

[0029] According to one embodiment of this application, the device further includes a tray and a cooler, the cooler being disposed on top of the battery cell along the direction of gravity, the battery cell and the heat exchange plate being disposed on the tray, the top end of the heat exchange plate along the direction of gravity being close to the cooler, and the bottom end of the heat exchange plate along the direction of gravity being close to the bottom of the tray.

[0030] Thirdly, this application provides a battery pack including a battery module as described in any of the above embodiments.

[0031] The battery pack provided in this application embodiment is equipped with the battery module as described in the above embodiment. The battery module has a heat exchange plate as described in the above embodiment disposed on the side of the battery cell. The heat exchange plate is provided with an upward flow channel and a downward flow channel connected end to end. When the temperature difference of the battery cell along the height direction is greater than the temperature threshold, the lower end of the heat exchange plate exchanges heat with the lower part of the battery cell and the tray. The refrigerant absorbs heat and evaporates at the lower end of the heat exchange plate, changing from a liquid phase to a gas phase. The gas phase refrigerant flows to the upper end of the heat exchange plate under the action of buoyancy. The upper end of the heat exchange plate exchanges heat with the upper part of the battery cell and the cooler. The gas phase refrigerant liquefies upon encountering cold and releasing heat at the upper end of the heat exchange plate. The liquid phase refrigerant flows to the lower end of the heat exchange plate under the action of gravity, forming a refrigerant reflux. Thus, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can achieve efficient heat exchange between the upper and lower regions of the battery cell, effectively reducing the overall temperature difference of the battery module. Compared to the design of placing a cooler at the top and bottom of the cell height, this reduces the cost and weight of the battery module and simplifies the structure.

[0032] Fourthly, this application provides an electrical device including a battery module as described in any of the above embodiments.

[0033] The electrical equipment provided in this application embodiment is equipped with the battery pack described in the above embodiment, which reduces the cost and weight of the battery module and improves the safety and reliability of the electrical equipment.

[0034] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0035] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0036] Figure 1 This is one of the structural schematic diagrams of the heat exchange plate provided in the embodiments of this application;

[0037] Figure 2 This is a second schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0038] Figure 3 This is one of the schematic diagrams of the assembly structure of the heat exchange plate and the battery cell provided in the embodiments of this application;

[0039] Figure 4 This is the third schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0040] Figure 5 This is the fourth schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0041] Figure 6 This is the fifth schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0042] Figure 7 This is the sixth schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0043] Figure 8 This is a second schematic diagram of the assembly structure of the heat exchange plate and the battery cell provided in the embodiments of this application;

[0044] Figure 9 This is the seventh schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0045] Figure 10 This is the eighth schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0046] Figure 11 This is the ninth schematic diagram of the heat exchange plate provided in the embodiments of this application;

[0047] Figure 12 This is a schematic diagram of the battery pack structure provided in the embodiments of this application;

[0048] Figure 13 This is a schematic diagram of the liquid filling of the heat exchange plate provided in the embodiment of this application.

[0049] Figure label:

[0050] Battery module 100;

[0051] Heat exchange plate 1, heat exchange channel 11, rising channel 111, fourth channel 1111, fifth channel 1112, falling channel 112, first channel 1121, second channel 1122, third channel 1123, sixth channel 113, evaporation chamber 114, condensation chamber 115;

[0052] Part 12, Part 23, First boss 131, Second boss 132, Groove 133, Positioning hole 134, Pressure relief valve 135, Welding bolt 136, Thinning area 137, First clearance groove 138, Second clearance groove 139, Injection pipe 14;

[0053] 2. Battery cell; 3. Tray; 4. Cooler; 5. Top insulation cotton; 6. Bottom insulation cotton; 7. Bottom protective plate; 8. Plastic bracket;

[0054] Vacuum pump 81, refrigerant storage tank 82, shut-off valve 83, connecting pipe 84. Detailed Implementation

[0055] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0056] The following is for reference. Figures 1-13 This application describes a heat exchange plate 1, a battery module 100, a battery pack, and an electrical device according to embodiments of the present application.

[0057] like Figure 1 and Figure 2 As shown in the embodiment of this application, the heat exchange plate 1 is disposed on the side of the battery cell 2. The heat exchange plate 1 can be integrated into the battery pack. The heat exchange plate 1 is in direct contact with the battery cell 2, which can reduce the temperature difference between the top and bottom of the battery cell 2 along the direction of gravity, improve the temperature uniformity of the battery cell 2, and reduce the risk of thermal runaway of the battery pack.

[0058] like Figure 6 As shown, the heat exchange plate 1 includes a heat exchange channel 11 and a refrigerant disposed within the heat exchange channel 11.

[0059] For example, the refrigerant can be a traditional refrigerant R245fa, acetone, or an environmentally friendly refrigerant, wherein the environmentally friendly refrigerant can be R1233zd(E), R1224yd(Z), and R1366mzz(Z).

[0060] It should be noted that the type of refrigerant selected must meet the following three aspects: First, when the battery pack is being cooled, the maximum operating temperature range of the battery cell 2 is usually 35℃~50℃, and the phase change temperature of the refrigerant located in the heat exchange channel 11 at the operating pressure should be between the maximum and minimum temperatures of the battery cell 2; Second, considering the structural safety of the battery pack and the structural cost of the pressure-resistant heat exchange plate 1, it is recommended that the operating pressure range of the refrigerant be 0-5 bar absolute pressure; Third, considering the risk of refrigerant leakage in the battery pack, the selected refrigerant must also meet the requirements of high dielectric constant, non-flammability, and good compatibility with the shell material.

[0061] like Figure 5 As shown, the heat exchange channel 11 includes an upward channel 111 and a downward channel 112 connected end to end. The upward channel 111 is used for refrigerant vaporization, and the downward channel 112 is used for refrigerant liquefaction to form refrigerant reflux.

[0062] When the temperature difference of cell 2 along the height direction is greater than the temperature threshold, the rising channel 111 is used for passing the refrigerant during or after evaporation, and the falling channel 112 is used for passing the refrigerant during or after condensation.

[0063] In this case, the temperature difference of the heat exchange plate 1 along the height direction is greater than the temperature threshold, the rising channel 111 is used for passing gaseous or gas-liquid mixed refrigerant, and the falling channel 112 is used for passing liquid or gas-liquid mixed refrigerant.

[0064] When the temperature difference of cell 2 along the height direction is less than or greater than the temperature threshold, the rising flow channel 111 is used for the refrigerant before evaporation, and the falling flow channel 112 is used for the refrigerant before condensation.

[0065] In this case, the temperature difference along the height direction of the heat exchange plate 1 is less than or greater than the temperature threshold, and both the rising flow channel 111 and the falling flow channel 112 can be used for refrigerant through gas-liquid mixing.

[0066] The temperature threshold can be determined based on factors such as the type of refrigerant, the height of the battery cell, and the height of the heat exchange plate 1.

[0067] In this embodiment, after the heat exchange plate 1 is installed on the side of the battery cell 2, the rising flow channel 111 extends from the direction near the bottom tray 3 of the battery cell 2 toward the direction near the top of the cooler 4 of the battery cell 2, and the falling flow channel 112 extends from the direction near the top of the cooler 4 of the battery cell 2 toward the direction near the bottom of the bottom tray 3 of the battery cell 2.

[0068] When cell 2 is working, the area at the bottom of cell 2 near the bottom of tray 3 has a high temperature, while the top of cell 2 has a lower temperature due to its proximity to cooler 4. Therefore, cell 2 has a temperature difference along its height.

[0069] like Figure 12 As shown, when the temperature difference of the battery cell along the height direction is greater than the temperature threshold, the heat exchange plate 1 is set on one or both sides of the battery cell 2. The lower end of the heat exchange plate 1 exchanges heat with the lower part of the battery cell 2 and the tray 3. The refrigerant absorbs heat and evaporates at the lower end of the heat exchange plate 1. The refrigerant changes from liquid phase to gas phase at the lower end of the heat exchange plate 1. Under the action of buoyancy, the gas phase refrigerant flows along the rising flow channel 111 to the upper end of the heat exchange plate 1. The upper end of the heat exchange plate 1 exchanges heat with the upper part of the battery cell 2 and the cooler 4. The gas phase refrigerant liquefies upon cooling and releasing heat at the upper end of the heat exchange plate 1. Under the action of gravity, the liquid phase refrigerant flows along the descending flow channel to the lower end of the heat exchange plate 1, forming a refrigerant reflux. Thus, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can achieve efficient heat exchange between the upper and lower regions of the battery cell 2, effectively reducing the overall temperature difference of the battery module 100.

[0070] To cool the battery cells, one related technology discloses a cooling structure comprising an inverted T-shaped heat spreader and a micro-needle fin liquid cooling plate. The inverted T-shaped heat spreader includes a vertical heat spreader and a horizontal heat spreader, using a high thermal conductivity metal as the matrix and graphene as the main dopant. The horizontal heat spreader is located between the micro-needle fin liquid cooling plate and the bottom of the lithium battery body, and is in close contact with both. The vertical heat spreader is located between two adjacent battery cells and is sealed to the battery cells. This invention enhances liquid cooling heat transfer through the micro-needle fin structure and improves the vertical thermal conductivity of the battery cells by placing high thermal conductivity heat spreaders between the cells. However, due to the need to fabricate complex micro-fin structures on the liquid cooling plate and the placement of heat spreaders between each pair of battery cells, the manufacturing cost is relatively high.

[0071] Related technology 2 discloses a thermal management structure for large-size cylindrical batteries, which combines a liquid-cooled plate with a heat pipe and a phase change material. The liquid-cooled plate is located at the bottom of the battery. The heat pipe consists of a flat section and a vertical section. The flat section is embedded in the liquid-cooled plate, and the vertical section is evenly distributed between the battery cells. Symmetrical aluminum corrugated plates are arranged on both sides. The battery compartment is filled with a phase change material. When the battery temperature is high, the battery transfers heat to the phase change material, and then the heat is transferred to the coolant in the liquid-cooled plate through the corrugated plates and the heat pipe, thus lowering the battery temperature. When the battery temperature is low, the coolant in the liquid-cooled plate transfers heat to the battery through the heat pipe, while the phase change material undergoes a liquid-solid phase change, releasing heat to the battery and raising its temperature. One drawback of this solution is its high cost. The heat pipe used is a bidirectional heat transfer heat pipe, requiring the sintering of capillary wicks inside, making the process more complex than that of gravity heat pipes. Furthermore, the large amount of phase change material used not only increases the cost but also the weight of the battery compartment.

[0072] Compared to other battery pack cooling solutions that combine gravity heat pipes and cooling plates, the heat exchange plate 1 of this application can utilize the height of the cell 2 itself to form a refrigerant reflux in the rising flow channel 111 and the falling flow channel 112 within the heat exchange plate 1 when there is a large temperature difference between the top and bottom of the cell 2, thereby achieving self-driving of the refrigerant under the action of gravity.

[0073] Meanwhile, by setting up the rising flow channel 111 and the falling flow channel 112, the flow channels of the gaseous refrigerant and the liquid refrigerant can be separated, reducing the flow resistance of the refrigerant in the heat exchange plate 1, thereby improving the heat exchange capacity and heat transfer limit of the heat exchange plate 1.

[0074] The heat exchange plate 1 provided in this embodiment of the application, by setting up an ascending flow channel 111 and a descending flow channel 112 connected end to end, when the temperature difference of the battery cell along the height direction is greater than the temperature threshold, the lower end of the heat exchange plate 1 exchanges heat with the lower part of the battery cell 2 and the tray 3. The refrigerant absorbs heat and evaporates at the lower end of the heat exchange plate 1, and the refrigerant changes from liquid phase to gas phase at the lower end of the heat exchange plate 1. The gas phase refrigerant flows to the upper end of the heat exchange plate 1 along the ascending flow channel 111 under the action of buoyancy. The upper end of the heat exchange plate 1 exchanges heat with the upper part of the battery cell 2 and the cooler 4. The gas phase refrigerant liquefies upon encountering cold and releasing heat at the upper end of the heat exchange plate 1. The liquid phase refrigerant flows to the lower end of the heat exchange plate 1 along the descending flow channel under the action of gravity, forming a refrigerant reflux. Thus, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can achieve efficient heat exchange between the upper and lower regions of the battery cell 2, effectively reducing the overall temperature difference of the battery module 100. Compared to the design of placing a cooler 4 above and below the height of the cell 2, this reduces the cost and weight of the battery module 100 and simplifies the structure.

[0075] In some embodiments, such as Figure 5As shown, the heat exchange channel 11 is annular, and an upward flow channel 111 is formed between the lowest point and the highest point of the inner ring outline of the heat exchange channel 11 along the first direction, and a downward flow channel 112 is formed between the highest point and the lowest point of the inner ring outline of the heat exchange channel 11 along the first direction.

[0076] The flow path of the rising flow path 111 can be greater than, equal to or less than the flow path of the falling flow path 112, and the specific flow path can be determined according to the working environment of the heat exchange plate 1 and the type of refrigerant.

[0077] Among them, such as Figure 5 As shown, the first direction can be counterclockwise, and the lowest and highest points of the inner ring outline of the heat exchange channel 11 are the dividing points of the rising channel 111 and the falling channel 112.

[0078] The lowest point of the inner ring outline of the heat exchange channel 11 can be located at the bottom of the heat exchange plate 1, that is, the lowest point of the inner ring outline of the heat exchange channel 11 is the position in the heat exchange channel 11 closest to the bottom of the battery cell 2 and the bottom of the tray 3.

[0079] The highest point of the inner ring outline of the heat exchange channel 11 can be located at the top of the heat exchange plate 1, that is, the highest point of the inner ring outline of the heat exchange channel 11 is the position in the heat exchange channel 11 closest to the top of the battery cell 2 and the cooler 4.

[0080] The top of the battery cell 2, being closer to the cooler 4, experiences a temperature drop first, creating a temperature difference with the bottom of the cell 2. The lowest point of the inner ring contour is close to the bottom of the heat exchange plate 1, which is located on the side of the cell 2 below and near the bottom of the tray 3, allowing the refrigerant at the lowest point of the inner ring contour of the heat exchange channel 11 to absorb heat and evaporate into a gaseous refrigerant. The highest point of the inner ring contour is close to the top of the heat exchange plate 1, which is located on the side of the cell 2 above and near the cooler 4, allowing the gaseous refrigerant to exchange heat with the cooling capacity of the cooler 4 and liquefy into a liquid refrigerant.

[0081] The flow path of the rising channel 111 is shorter than that of the falling channel 112. The flow resistance of the gaseous refrigerant in the rising channel 111 is smaller, and the gaseous refrigerant generated by evaporation tends to rise from the rising channel 111. Since the flow resistance of the refrigerant circulation is reduced, the convective heat transfer capacity of the refrigerant in the heat exchange plate 1 is improved, thereby improving the heat transfer capacity between the upper and lower parts of the battery cell 2, reducing the temperature difference between the upper and lower parts of the battery cell 2, and improving the temperature uniformity of the battery cell 2.

[0082] like Figure 5 and Figure 6As shown, the working principle of heat exchange plate 1 is as follows: When the battery pack is charged and discharged under high temperature conditions and cooling is activated, the top of the battery cell 2, being closer to the cooler 4, experiences a temperature drop first, creating a temperature difference with the bottom of the cell 2. Since the lower part of the large surface area, the bottom, and the tray 3 of the cell 2 are at higher temperatures, heat is transferred to the refrigerant inside the heat exchange plate 1. The refrigerant near the high-temperature zone of the cell 2 evaporates first. The vaporized refrigerant and the gas-liquid mixture formed during evaporation rise along the heat exchange channel 11 to the top of the heat exchange plate 1 under buoyancy. The vaporized refrigerant and the gas-liquid mixture release heat to the upper part of the cell 2 and the cooler 4, condensing into a liquid state. Most of the liquid refrigerant and the condensed gas-liquid mixture flow back to the bottom of the heat exchange plate 1 along the heat exchange channel 11 under gravity, forming an evaporation-condensation cycle.

[0083] In some embodiments, such as Figure 4 As shown, the descending flow channel 112 includes a first flow channel 1121, a second flow channel 1122 and a third flow channel 1123 connected in sequence, and the ascending flow channel 111 includes a fourth flow channel 1111 and a fifth flow channel 1112 connected in sequence.

[0084] The inner contour of the rising channel 111 increases monotonically along the direction of gravity, that is, the height increases sequentially from the end of the fourth channel 1111 away from the fifth channel 1112 to the end of the fifth channel 1112 away from the fourth channel 1111.

[0085] The inner contour of the descending flow channel 112 decreases monotonically along the direction of gravity, that is, the height from the end of the first flow channel 1121 connected to the fifth flow channel 1112 to the end of the third flow channel 1123 connected to the fourth flow channel 1111 decreases sequentially.

[0086] The lower end of the first flow channel 1121 is connected to the upper end of the second flow channel 1122, the lower end of the second flow channel 1122 is connected to the upper end of the third flow channel 1123, the lower end of the third flow channel 1123 is connected to the lower end of the fourth flow channel 1111, the upper end of the fourth flow channel 1111 is connected to the lower end of the fifth flow channel 1112, and the upper end of the fifth flow channel 1112 is connected to the upper end of the first flow channel 1121.

[0087] The upper end of the fifth flow channel 1112 is higher than the upper end of the second flow channel 1122 along the direction of gravity, that is, the upper end of the first flow channel 1121 is higher than the lower end of the first flow channel 1121 along the direction of gravity. The first flow channel 1121 is inclined downward along the direction of gravity, and the liquid refrigerant can flow downward along the first flow channel 1121 to the second flow channel 1122 under the action of gravity.

[0088] like Figure 5As shown, when the temperature difference between the top and bottom of the battery cell 2 is small, its working principle is as follows: Due to the higher temperature of the lower part of the large surface of the battery cell 2, the bottom, and the tray 3, heat is transferred to the refrigerant inside the heat exchange plate 1, causing the refrigerant at the lower end of the third flow channel 1123 and the lower end of the fourth flow channel 1111 to evaporate first and form bubbles. The gaseous refrigerant and the gas-liquid mixture formed by evaporation rise along the third flow channel 1123 and the fourth flow channel 1111 under the action of buoyancy to reach the top of the heat exchange plate 1, that is, the first... At the upper end of the five-channel 1112, the gaseous refrigerant releases heat to the upper part of the battery cell 2 and the cooler 4. The gaseous refrigerant condenses into a liquid state. Most of the liquid and gas-liquid mixture of refrigerant flows back to the bottom of the heat exchange plate 1 along the first channel 1121 and the second channel 1122 under the action of gravity. A liquid film is formed on the wall of the first channel 1121, part of the wall of the second channel 1122 and part of the wall of the fifth channel 1112. A small portion of the liquid flows back along the wall of the fifth channel 1112 to form an evaporation-condensation cycle.

[0089] In this embodiment, the first flow channel 1121 to the fifth flow channel 1112 can be a straight flow or a bend flow channel, as long as it can meet the upward trend of the rising flow channel 111 and the downward trend of the falling flow channel 112.

[0090] All variations in the above scheme, including combinations, splits, additions, and subtractions of the flow channels, are within the protection scope of this invention.

[0091] In some embodiments, such as Figure 4 As shown, the second flow channel 1122 and the fifth flow channel 1112 extend along the direction of gravity, which can reduce the circulation resistance of the refrigerant. The liquid phase refrigerant flows back along the second flow channel 1122, and the gas phase refrigerant rises along the fifth flow channel 1112.

[0092] The flow area of ​​the fifth flow channel 1112 is larger than that of the second flow channel 1122, meaning that the hydraulic diameter of the fifth flow channel 1112 is larger than that of the second flow channel 1122. Therefore, the flow resistance of the gaseous refrigerant in the rising flow channel 111 is smaller, and the gaseous refrigerant generated by evaporation tends to rise from the rising flow channel 111.

[0093] In some embodiments, the second flow channel 1122 and the fifth flow channel 1112 extend along the direction of gravity, the liquid refrigerant flows back along the second flow channel 1122, and the gaseous refrigerant rises along the fifth flow channel 1112, which can reduce the circulation resistance of the refrigerant.

[0094] In some embodiments, such as Figure 4As shown, the flow area of ​​the fifth flow channel 1112 is larger than that of the second flow channel 1122. That is, the hydraulic diameter d2 of the fifth flow channel 1112 is larger than that of the second flow channel 1122. Therefore, the flow resistance of the gaseous refrigerant in the rising flow channel 111 is smaller, and the gaseous refrigerant generated by evaporation tends to rise from the rising flow channel 111.

[0095] In some embodiments, such as Figure 4 As shown, the following conditions are met: 0°<θ1≤25°, 0°<θ2≤45°, 0°<θ3≤45°, where θ1 is the tilt angle of the first flow channel 1121 with respect to the horizontal direction, θ2 is the tilt angle of the third flow channel 1123 with respect to the horizontal direction, and θ3 is the tilt angle of the fourth flow channel 1111 with respect to the horizontal direction.

[0096] The first flow channel 1121 is inclined downward along the direction of gravity, and the inclination angle θ1 with respect to the horizontal direction can be 5°, 10°, 15°, 20° or 25°, so that the liquid refrigerant can flow back along the first flow channel 1121 and reduce the refrigerant's backflow resistance.

[0097] The third flow channel 1123 is inclined downward along the direction of gravity, and the inclination angle θ2 with respect to the horizontal direction can be 5°, 15°, 25°, 30° or 45°, so that the liquid refrigerant can flow back along the third flow channel 1123, reducing the refrigerant's backflow resistance.

[0098] The fourth flow channel 1111 is inclined upward along the direction of gravity, and the inclination angle θ3 with the horizontal direction can be 5°, 15°, 25°, 30° or 45°, so that the gaseous refrigerant can rise along the third flow channel 1123 and reduce the circulation resistance of the refrigerant.

[0099] In this embodiment, by setting the tilt angles of the first flow channel 1121, the third flow channel 1123 and the fourth flow channel 1111, the refrigerant backflow resistance can be reduced and the heat exchange effect of the heat exchange plate 1 can be improved.

[0100] In some embodiments, such as Figure 4 As shown, the following conditions are met: 0°<θ1≤25°, 0°<θ2≤45°, where θ1 is the inclination angle of the first flow channel 1121 with respect to the horizontal direction, and θ2 is the inclination angle of the third flow channel 1123 with respect to the horizontal direction.

[0101] The first flow channel 1121 is inclined downward along the direction of gravity, and the inclination angle θ1 with respect to the horizontal direction can be 5°, 10°, 15°, 20° or 25°, so that the liquid refrigerant can flow back along the first flow channel 1121; the third flow channel 1123 is inclined downward along the direction of gravity, and the inclination angle θ2 with respect to the horizontal direction can be 5°, 15°, 25°, 30° or 45°.

[0102] In this embodiment, by setting the tilt angle of the first flow channel 1121 and the third flow channel 1123, the refrigerant backflow resistance can be reduced and the heat exchange effect of the heat exchange plate 1 can be improved.

[0103] In some embodiments, such as Figure 4 As shown, the following conditions are met: 0°<θ1≤25°, where θ1 is the tilt angle of the first flow channel 1121 with respect to the horizontal direction; and 0°<θ3≤45°, where θ3 is the tilt angle of the fourth flow channel 1111 with respect to the horizontal direction.

[0104] The first flow channel 1121 is inclined downward along the direction of gravity, and the inclination angle θ1 with respect to the horizontal direction can be 5°, 10°, 15°, 20° or 25°, so that the liquid refrigerant can flow back along the first flow channel 1121; the fourth flow channel 1111 is inclined upward along the direction of gravity, and the inclination angle θ3 with respect to the horizontal direction can be 5°, 15°, 25°, 30° or 45°, so that the gaseous refrigerant can rise along the third flow channel 1123.

[0105] In this embodiment, by setting the tilt angle of the first flow channel 1121 and the fourth flow channel 1111, the refrigerant backflow resistance can be reduced and the heat exchange effect of the heat exchange plate 1 can be improved.

[0106] In some embodiments, such as Figure 4 As shown, the following conditions are met: 0°<θ2≤45°, where θ2 is the tilt angle of the third flow channel 1123 with respect to the horizontal direction; and 0°<θ3≤45°, where θ3 is the tilt angle of the fourth flow channel 1111 with respect to the horizontal direction.

[0107] The third flow channel 1123 is inclined downward along the direction of gravity, and the inclination angle θ2 with respect to the horizontal direction can be 5°, 15°, 25°, 30° or 45°, so that the liquid refrigerant can flow back along the third flow channel 1123; the fourth flow channel 1111 is inclined upward along the direction of gravity, and the inclination angle θ3 with respect to the horizontal direction can be 5°, 15°, 25°, 30° or 45°, so that the gaseous refrigerant can rise along the third flow channel 1123.

[0108] In this embodiment, by setting the tilt angle of the third flow channel 1123 and the fourth flow channel 1111, the refrigerant backflow resistance can be reduced and the heat exchange effect of the heat exchange plate 1 can be improved.

[0109] In some embodiments, such as Figure 4 As shown, the following condition is met: 0°<θ1≤25°, where θ1 is the inclination angle of the first flow channel 1121 relative to the horizontal direction.

[0110] The first flow channel 1121 is inclined downward along the direction of gravity, and the inclination angle θ1 with respect to the horizontal direction can be 5°, 10°, 15°, 20° or 25°, so that the liquid refrigerant can flow back along the first flow channel 1121 and reduce the refrigerant's backflow resistance.

[0111] In some embodiments, such as Figure 4 As shown, the following condition is satisfied: 0°<θ2≤45°, where θ2 is the inclination angle of the third flow channel 1123 to the horizontal direction.

[0112] The third flow channel 1123 is inclined downward along the direction of gravity, and the inclination angle θ2 with respect to the horizontal direction can be 5°, 15°, 25°, 30° or 45°, so that the liquid refrigerant can flow back along the third flow channel 1123, reducing the refrigerant's backflow resistance.

[0113] In some embodiments, such as Figure 4 As shown, the following condition is satisfied: 0°<θ3≤45°, where θ3 is the inclination angle of the fourth flow channel 1111 to the horizontal direction.

[0114] The fourth flow channel 1111 is inclined upward along the direction of gravity, and the inclination angle θ3 with the horizontal direction can be 5°, 15°, 25°, 30° or 45°, so that the gaseous refrigerant can rise along the third flow channel 1123 and reduce the circulation resistance of the refrigerant.

[0115] In this embodiment, as Figure 6 As shown, the heat exchange plate 1 can achieve self-drive under gravity by designing the internal flow channel inclination angle and size, utilizing the height of the battery cell 2 itself, and forming a pressure difference between the gas column and liquid column in the rising flow channel 111 and the falling flow channel 112 within the heat exchange plate 1 when the temperature difference between the upper and lower parts of the battery is large.

[0116] In some embodiments, such as Figure 4 As shown, the heat exchange channel 11 also includes a sixth channel 113, which is located between the third channel 1123 and the fourth channel 1111. The sixth channel 113 extends horizontally and is close to the bottom of the heat exchange plate 1 along the direction of gravity.

[0117] The sixth flow channel 113 is located at the lowest point of the heat exchange plate 1. When a temperature difference is formed between the upper and lower parts of the battery cell 2, the refrigerant in the sixth flow channel 113 evaporates first.

[0118] By setting a sixth flow channel 113, the length of the heat exchange flow channel 11 near the bottom of the cell 2 can be increased, thereby increasing the heat exchange area between the heat exchange flow channel 11 and the high-temperature zone at the bottom of the cell 2 and improving the heat exchange effect.

[0119] In some embodiments, such as Figure 4As shown, the inclination angle of the fourth flow channel 1111 to the horizontal direction is greater than that of the third flow channel 1123 to the horizontal direction. As a result, the flow resistance of the gaseous refrigerant in the fourth flow channel 1111 is smaller, and the gaseous refrigerant generated by evaporation tends to rise from the fourth flow channel 1111, which reduces the flow resistance of the circulation and improves the convective heat transfer capacity of the refrigerant in the heat exchange plate 1.

[0120] like Figure 6 As shown, when the heat generated by cell 2 is large, the temperature difference between the top and bottom of cell 2 is large. Its working principle is as follows: The increased heat input from cell 2 and tray 3 to heat exchange plate 1 increases the dryness of the refrigerant at the bottom of heat exchange plate 1. Due to the larger horizontal inclination angle of the fourth flow channel 1111, the larger hydraulic diameter of the fifth flow channel 1112 compared to the second flow channel 1122, and the shorter flow path of the rising flow channel 111 compared to the descending flow channel 112, the flow resistance of the gaseous refrigerant in the rising flow channel 111 is smaller, and the gaseous refrigerant generated by evaporation tends to rise from the rising flow channel 111. At the top of heat exchange plate 1, the gaseous refrigerant is released towards the upper part of cell 2 and the cooler 4. The refrigerant condenses into a liquid state and flows back along the first flow channel 1121 under the action of gravity, forming a liquid column in the descending flow channel 112. The liquid level in the descending flow channel 112 and the rising flow channel 111 forms a height difference. Driven by the pressure difference generated by the gas-liquid density difference, the refrigerant forms a unidirectional circulation in the heat exchange plate 1. Compared with the integrated gravity heat pipe, the heat exchange plate 1 of this application separates the flow channels of gaseous and liquid refrigerant, reduces the flow resistance of circulation, improves the convective heat transfer capacity of refrigerant in the heat exchange plate 1, thereby improving the heat transfer capacity between the upper and lower parts of the battery cell 2, reducing the temperature difference between the upper and lower parts of the battery cell 2, and improving the temperature uniformity of the battery cell 2.

[0121] Among them, the first flow channel 1121 can be a flow channel with equal width, or a flow channel with a gradually increasing or decreasing cross-sectional area; the third flow channel 1123 can be a flow channel with equal width, or a flow channel with a gradually increasing or decreasing cross-sectional area; the fourth flow channel 1111 can be a flow channel with equal width, or a flow channel with a gradually increasing or decreasing cross-sectional area.

[0122] The flow cross-sectional area of ​​the flow channel is determined based on the height of the battery cell and the specifications of the heat exchange plate 1.

[0123] In some embodiments, such as Figure 9 As shown, the cross-sectional area of ​​the fourth flow channel 1111 gradually increases from the end connected to the third flow channel 1123 to the end connected to the fifth flow channel 1112 to form an evaporation chamber 114. This can increase the flow channel length of the fourth flow channel 1111 near the bottom of the battery cell 2, thereby increasing the heat exchange area between the fourth flow channel 1111 and the high-temperature zone where the bottom of the battery cell 2 is located, increasing the evaporation rate, increasing the refrigerant circulation rate, and thus improving the heat exchange effect.

[0124] The cross-sectional area of ​​the first flow channel 1121 gradually increases from the end connected to the fifth flow channel 1112 to the end connected to the second flow channel 1122 to form a condensing cavity 115. This can increase the flow channel length of the first flow channel 1121 near the top of the battery cell 2 and the cooler 4, thereby increasing the heat exchange area between the first flow channel 1121 and the low-temperature zone where the top of the battery cell 2 and the cooler 4 are located, increasing the condensation amount, increasing the refrigerant circulation rate, and thus improving the heat exchange effect.

[0125] In some embodiments, the first flow channel 1121 includes a first guide surface and a condensing surface. The condensing surface extends along the top of the heat exchange plate 1. The first guide surface slopes downward along the direction of gravity from one end communicating with the fifth flow channel 1112 to the other end communicating with the second flow channel 1122, thereby further increasing the heat exchange area between the condensing cavity 115 and the top of the battery cell 2 and the low-temperature zone where the cooler 4 is located.

[0126] The fourth flow channel 1111 includes a second guide surface and an evaporation surface. The evaporation surface extends along the bottom end of the heat exchange plate 1. The second guide surface slopes upward along the direction of gravity from the end connected to the third flow channel 1123 to the end connected to the fifth flow channel 1112, thereby further increasing the heat exchange area between the fourth flow channel 1111 and the high-temperature zone at the bottom of the battery cell 2, increasing the evaporation rate, increasing the refrigerant circulation rate, and thus improving the heat exchange effect.

[0127] In some embodiments, such as Figure 5 and Figure 9 As shown, the first flow channel 1121, the second flow channel 1122, the third flow channel 1123 and the fourth flow channel 1111 each include two sets. The two sets of the first flow channel 1121, the two sets of the second flow channel 1122, the two sets of the third flow channel 1123 and the two sets of the fourth flow channel 1111 are symmetrically distributed on both sides of the fifth flow channel 1112 with the fifth flow channel 1112 as the axis of symmetry.

[0128] In this embodiment, the heat exchange channels 11 are symmetrically arranged, and the symmetrically arranged channels share the fifth channel 1112. This can improve the uniformity of the refrigerant flow in the first channel 1121, the second channel 1122, the third channel 1123 and the fourth channel 1111 on both sides, increase the refrigerant circulation rate, thereby improving the heat exchange effect and improving the temperature uniformity of the battery cell 2.

[0129] In some embodiments, such as Figure 9 and Figure 10 As shown, the heat exchange plate 1 also includes a pressure relief valve 135, which is connected to the heat exchange channel 11.

[0130] In this embodiment, the pressure relief valve 135 has its pressure relief port facing the battery cell 2. When the battery cell 2 experiences thermal runaway, the refrigerant temperature rises sharply, increasing the pressure inside the heat exchange plate 1. When this pressure exceeds the threshold of the pressure relief valve 135, the pressure relief valve 135 opens, and liquid refrigerant is sprayed from the pressure relief port into the battery pack, directly contacting the battery cell 2. The liquid refrigerant absorbs heat from the battery cell 2 and evaporates, thereby reducing the temperature of the battery cell 2, suppressing thermal runaway, and reducing the hazards of thermal runaway.

[0131] The pressure relief valve 135 is located near the bottom of the heat exchange plate 1 in the heat exchange channel 11 and is positioned below the liquid surface of the refrigerant. When the pressure relief valve 135 is open, the volume of liquid refrigerant sprayed from the heat exchange channel 11 is increased, thereby improving the cooling effect of the cell 2 in case of thermal runaway.

[0132] In some embodiments, the outer contour lines of the fourth flow channel 1111 located on both sides of the fifth flow channel 1112 extend horizontally and are connected, so that the liquid refrigerant on both sides can be sprayed out from the pressure relief port, thereby maximizing the cooling effect of the refrigerant inside the heat exchange plate 1 when the cell 2 experiences thermal runaway.

[0133] In some embodiments, such as Figure 8 As shown, a welding bolt 136 is provided on the heat exchange plate 1. The welding bolt 136 is connected to the heat exchange channel 11, and the pressure relief valve 135 is sealed to the welding bolt 136.

[0134] The welding bolt 136 can be fixed to the heat exchange plate 1 by brazing, and the sealing function can be achieved by fixing it to the welding bolt 136 by thread.

[0135] In some embodiments, a protrusion is provided on one side of the heat exchange plate 1 in the horizontal direction, a portion of the heat exchange flow channel 11 is provided in the protrusion, and a welding bolt 136 is provided on one side of the protrusion.

[0136] In this embodiment, when the temperature difference between the top and bottom of the battery cell 2 is large, due to the large flow cross-sectional area of ​​the evaporation chamber 114 formed by the fourth flow channel 1111, the vapor generated by the refrigerant absorbing heat cannot carry the liquid refrigerant into the fifth flow channel 1112. The thermodynamic state of the refrigerant in the fifth flow channel 1112 is saturated or superheated gas phase. Driven by the pressure difference formed between the second flow channel 1122 and the fifth flow channel 1112, the refrigerant circulates to achieve heat exchange between the refrigerant and the battery cell 2. When the battery cell 2 experiences thermal runaway, the refrigerant temperature rises sharply, increasing the pressure inside the heat exchange plate 1. When this pressure exceeds the threshold of the pressure relief valve 135, the pressure relief valve 135 opens, and the liquid refrigerant is sprayed from the pressure relief port into the battery pack and directly contacts the battery cell 2, absorbing heat from the battery cell 2 and evaporating. The temperature of the battery cell 2 is thus reduced, achieving the function of suppressing thermal runaway of the battery cell 2.

[0137] In some embodiments, such as Figure 11As shown, the heat exchange plate 1 is also provided with a thinning zone 137, which is located in the heat exchange channel 11.

[0138] In this embodiment, the welding bolts and pressure relief valve 135 in the above embodiment can be replaced with a local thinning area 137. The structural strength of the thinning area 137 is weaker than that of other areas of the heat exchange plate 1 forming the heat exchange channel 11. Therefore, the pressure value that the thinning area 137 can withstand is less than the pressure value of other areas of the heat exchange channel 11.

[0139] In this embodiment, when the temperature difference between the top and bottom of the battery cell 2 is large, due to the large flow cross-sectional area of ​​the evaporation chamber 114 formed by the fourth flow channel 1111, the vapor generated by the refrigerant absorbing heat cannot carry the liquid refrigerant into the fifth flow channel 1112. The thermodynamic state of the refrigerant in the fifth flow channel 1112 is saturated or superheated gas phase. Driven by the pressure difference formed between the second flow channel 1122 and the fifth flow channel 1112, the refrigerant circulates to achieve heat exchange between the refrigerant and the battery cell 2. When the battery cell 2 experiences thermal runaway, the refrigerant temperature rises sharply, increasing the pressure inside the heat exchange plate 1. When the pressure exceeds the pressure threshold that the thinning zone 137 can withstand, the refrigerant breaks through the thinning zone 137, and the liquid refrigerant sprays out from the thinning zone 137 into the battery pack and directly contacts the battery cell 2, absorbing heat from the battery cell 2 and evaporating, thereby reducing the temperature of the battery cell 2 and achieving the function of suppressing thermal runaway of the battery cell 2.

[0140] In some embodiments, the thickness of the thinning region 137 is in the range of 0.05 mm to 0.5 mm, for example, it can be 0.05 mm, 0.1 mm, 0.2 mm, 0.35 mm, 0.4 mm or 0.5 mm. The specific thickness is determined according to the actual burst pressure requirement of the heat exchange plate 1. This structure can achieve the function of suppressing thermal runaway of the battery cell 2 at a lower cost.

[0141] In this embodiment, by setting a thinning zone 137 or a pressure relief valve 135, when thermal runaway occurs in the battery cell 2, the liquid refrigerant can be sprayed out to the battery cell 2 using the pressure inside the heat exchange plate 1, so that the battery cell 2 can be cooled down quickly and the thermal runaway process can be suppressed.

[0142] In some embodiments, such as Figure 7 As shown, the heat exchange plate 1 includes a first part 12 and a second part 13, which together define the heat exchange channel 11.

[0143] The materials of the first part 12 and the second part 13 can be copper alloy or aluminum alloy, and the first part 12 and the second part 13 can be formed into one piece by brazing.

[0144] The heat exchange channel 11 can be located in the first part 12 or the second part 13, or part of the channel can be located in the first part 12 and the other part of the channel can be located in the second part 13.

[0145] Part 12 and Part 13 can be formed by stamping followed by machining, and then brazed together.

[0146] In some embodiments, the inner side of the first part 12 is provided with a flow channel groove of the heat exchange channel 11, the port of the flow channel groove is open, and the second part 13 is a flat plate structure. When the first part 12 and the second part 13 are connected, the second part 13 covers the groove opening of the flow channel groove of the first part 12, and the first part 12 and the second part 13 together define the heat exchange channel 11.

[0147] In some embodiments, a first flow channel 1121 groove of heat exchange channel 11 is provided on the inner side of the first part 12, and a second flow channel 1122 groove of heat exchange channel 11 is provided on the inner side of the second part 13. The first flow channel 1121 groove and the second flow channel 1122 groove are aligned and both ports are open. When the first part 12 and the second part 13 are connected, the first flow channel 1121 groove and the second flow channel 1122 groove are connected to form a closed heat exchange channel 11. The first part 12 and the second part 13 together define the heat exchange channel 11.

[0148] In some embodiments, the first portion 12 and the second portion 13 have at least the following structure:

[0149] Firstly, such as Figure 7 As shown, a first protrusion 131 and a second protrusion 132 are provided on the outer side of the first part 12 and the outer side of the second part 13. The first protrusion 131 and the second protrusion 132 are arranged at intervals along the direction of gravity. The first protrusion 131 and the second protrusion 132 are used to connect with the battery cell 2.

[0150] In this embodiment, the heat exchange plate 1 is provided with a first protrusion 131 and a second protrusion 132 on both sides, and both sides of the heat exchange plate 1 can exchange heat with the battery cell 2, which is suitable for situations where there are battery cells 2 on both sides.

[0151] The first protrusion 131 and the second protrusion 132 are spaced apart, and a groove 133 is formed between the first protrusion 131 and the second protrusion 132. The first protrusion 131 is away from the top surface of the first part 12 and the second protrusion 132 is away from the top surface of the first part 12 for connection with the battery cell 2.

[0152] In this way, by setting the first protrusion 131 and the second protrusion 132 separately to form a groove 133, on the one hand, the heat leakage from the middle of the heat exchange plate 1 to the battery cell 2 along the direction of gravity can be reduced, thereby increasing the heat exchange at the bottom and top of the battery cell 2; on the other hand, the heat leakage of the battery cell 2 under low temperature conditions can be reduced.

[0153] Secondly, such as Figure 2As shown, the outer side of the first part 12 is provided with a first protrusion 131 and a second protrusion 132. The first protrusion 131 and the second protrusion 132 are arranged at intervals along the direction of gravity. The first protrusion 131 and the second protrusion 132 are used to connect with the battery cell 2.

[0154] In this embodiment, the first part 12 of the heat exchange plate 1 is connected to the outside of the battery cell 2 to dissipate heat from one side of the battery cell 2, which is suitable for situations where there is a battery cell 2 on one side.

[0155] Thirdly, such as Figure 2 As shown, the outer side of the second part 13 is provided with a first protrusion 131 and a second protrusion 132. The first protrusion 131 and the second protrusion 132 are arranged at intervals along the direction of gravity. The first protrusion 131 and the second protrusion 132 are used to connect with the battery cell 2.

[0156] In this embodiment, the second part 13 of the heat exchange plate 1 is connected to the outside of the battery cell 2 to dissipate heat from one side of the battery cell 2, which is suitable for situations where there is a battery cell 2 on one side.

[0157] In some embodiments, the top surface of the first boss 131 facing away from the first portion 12 and the top surface of the second boss 132 facing away from the first portion 12 are both coated with thermally conductive structural adhesive, and the first boss 131 and the second boss 132 are connected to the battery cell 2 through the thermally conductive structural adhesive.

[0158] In this embodiment, the heat exchange plate 1 is bonded and heat transferred between the thermally conductive structural adhesive and the battery cell 2.

[0159] In some embodiments, the first part 12 and the second part 13 are positioned together to fix their relative positions during brazing.

[0160] For example, such as Figure 1 As shown, one of the first part 12 and the second part 13 is provided with a positioning hole 134, and the other of the first part 12 and the second part 13 is provided with a positioning pin; or, both the first part 12 and the second part 13 are provided with positioning holes 134, and the heat exchange plate 1 also includes a positioning pin, which passes through the positioning hole 134 of the first part 12 and the positioning hole 134 of the second part 13.

[0161] In some embodiments, such as Figure 7 As shown, the heat exchange plate 1 is also provided with a liquid injection pipe 14, which is connected to the heat exchange channel 11 and is used to inject refrigerant into the heat exchange channel 11.

[0162] Wherein, if the first part 12 is provided with a heat exchange channel 11, the liquid injection pipe 14 can be integrated with the first part 12 by brazing; or, if the second part 13 is provided with a heat exchange channel 11, the liquid injection pipe 14 can be integrated with the second part 13 by brazing; or, if both the first part 12 and the second part 13 are provided with heat exchange channels 11, the liquid injection pipe 14 can be integrated with the first part 12 and the second part 13 by brazing.

[0163] The liquid injection pipe 14 can be set at the top of the heat exchange plate 1 along the direction of gravity, so as to utilize the gravity of the refrigerant to inject liquid and improve the injection rate.

[0164] In some embodiments, such as Figure 2 and Figure 7 As shown, a first clearance groove 138 is provided on the top of the heat exchange plate 1, and the inlet of the liquid injection pipe 14 is located in the first clearance groove 138 so that when the heat exchange plate 1 and the battery cell 2 are assembled, the outer edge of the heat exchange plate 1 does not protrude from the outer contour of the battery cell 2.

[0165] In some embodiments, such as Figure 2 and Figure 7 As shown, the heat exchange plate 1 is also provided with a second clearance groove 139, which is used to avoid the temperature detection device of the battery cell 2.

[0166] In some embodiments, the heat exchange plate 1 satisfies: 21.5% ≤ V1 / V2 ≤ 64.5%. For example, V1 / V2 can be 25%, 35%, 43%, 50%, or 60%, and the specific filling rate can be determined by the actual minimum thermal resistance.

[0167] Wherein, V1 is the amount of refrigerant charged into the heat exchange channel 11, V2 is the total capacity of the heat exchange channel 11, and V1 / V2 is the filling rate of the heat exchange channel 11.

[0168] like Figure 13 As shown, the refrigerant charging method for heat exchange plate 1 is as follows: The liquid injection port of heat exchange plate 1 is connected to refrigerant storage tank 82 via pipelines and vacuum pump 81. The shut-off valve 83 is opened, and vacuum pump 81 is started to evacuate the heat exchange channel 11 and pipeline of heat exchange plate 1. After completion, shut-off valve 83 is closed, and valve on refrigerant storage tank 82 is opened to allow refrigerant to be injected into heat exchange channel 11 of heat exchange plate 1. When the liquid filling rate reaches the set volume liquid filling rate, valve on refrigerant storage tank 82 is closed to stop charging. The liquid injection port of injection pipe 14 is flattened using a sealing mold, and connecting pipe 84 is removed. The liquid injection port is welded and sealed using laser welding or argon arc welding.

[0169] In some embodiments, the heat exchange plate 1 includes a body and an insulating layer, the insulating layer being disposed on the outer surface of the body, and the heat exchange channel 11 being disposed within the body.

[0170] Before the heat exchange plate 1 is assembled with the battery cell 2, an insulating layer needs to be set on the surface of the heat exchange plate 1 body to improve the insulation performance of the heat exchange plate 1, thereby reducing the risk of arcing and fire caused when the explosion-proof valve of the battery cell 2 is opened.

[0171] The insulating layer can be epoxy resin powder or epoxy resin paint, or a wrapping layer formed by insulating PI film or PET film.

[0172] This application embodiment also provides a battery module 100, such as Figure 3 As shown, it includes a battery cell 2 and a heat exchange plate 1 as described in any of the above embodiments, with the heat exchange plate 1 disposed on the side of the battery cell 2.

[0173] During assembly, the outer contour of the heat exchange plate 1 and the outer contour of the battery cell 2 are kept flush to improve heat dissipation and reduce the encroachment of the heat exchange plate 1 on the battery box, thereby improving the accuracy of assembly.

[0174] The battery module 100 provided in this embodiment uses a heat exchange plate 1 as described in the above embodiment, which is provided on the side of the battery cell 2. The heat exchange plate 1 is provided with an upward flow channel 111 and a downward flow channel 112 connected end to end. When the temperature difference of the battery cell along the height direction is greater than the temperature threshold, the lower end of the heat exchange plate 1 exchanges heat with the lower part of the battery cell 2 and the tray 3. The refrigerant absorbs heat and evaporates at the lower end of the heat exchange plate 1, changing from a liquid phase to a gas phase. The gas phase refrigerant floats... Under the action of force, the refrigerant flows along the rising channel 111 to the upper end of the heat exchange plate 1. The upper end of the heat exchange plate 1 exchanges heat with the upper part of the cell 2 and the cooler 4. The gaseous refrigerant liquefies upon cooling and releasing heat at the upper end of the heat exchange plate 1, and the liquid refrigerant flows along the lower rising channel to the lower end of the heat exchange plate 1 under the action of gravity, forming a refrigerant reflux. Thus, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can achieve efficient heat exchange between the upper and lower regions of the cell 2, effectively reducing the overall temperature difference of the battery module 100. Compared with the scheme of setting one cooler 4 at the top and one at the bottom of the cell 2 in the height direction, the cost and weight of the battery module 100 are reduced, and the structure is simple.

[0175] In some embodiments, the battery module 100 further includes a tray 3 and a cooler 4. The cooler 4 is disposed on top of the battery cell 2 along the direction of gravity. The battery cell 2 and the heat exchange plate 1 are disposed on the tray 3. The top end of the heat exchange plate 1 along the direction of gravity is close to the cooler 4, and the bottom end of the heat exchange plate 1 along the direction of gravity is close to the bottom of the tray 3.

[0176] In some embodiments, such as Figure 12As shown, the heat exchange plate 1 is installed on both sides of the battery module 100 or in the middle of adjacent battery modules 100. Along the direction of gravity, above the battery module 100, from bottom to top, the cooler 4 and top insulation cotton 5 are installed sequentially. The cooler 4, the top of the battery module 100, and the top of the heat exchange plate 1 are all bonded together using thermally conductive structural adhesive. The tray 3, the bottom of the battery module 100, and the bottom of the heat exchange plate 1 are all bonded together using thermally conductive structural adhesive. A plastic bracket 8 is placed between the tray 3 and the heat exchange plate 1 to fill the gap in the battery pack in a second direction, where the second direction is the lateral direction perpendicular to the direction of gravity.

[0177] Below the tray 3, from top to bottom, are installed bottom insulation cotton 6 and bottom protective plate 7.

[0178] This application also provides a battery pack, including a battery module 100 as described in any of the above embodiments.

[0179] The battery pack provided in this application embodiment includes a battery module 100 as described in the above embodiment. The battery module 100 has a heat exchange plate 1 as described in the above embodiment disposed on the side of the battery cell 2. The heat exchange plate 1 is provided with an upward flow channel 111 and a downward flow channel 112 connected end to end. When the temperature difference of the battery cell along the height direction is greater than the temperature threshold, the lower end of the heat exchange plate 1 exchanges heat with the lower part of the battery cell 2 and the tray 3. The refrigerant absorbs heat and evaporates at the lower end of the heat exchange plate 1, and the refrigerant undergoes a phase change from liquid to liquid at the lower end of the heat exchange plate 1. In the gaseous phase, the gaseous refrigerant flows along the rising channel 111 to the upper end of the heat exchange plate 1 under the action of buoyancy. The upper end of the heat exchange plate 1 exchanges heat with the upper part of the battery cell 2 and the cooler 4. The gaseous refrigerant liquefies upon cooling and releasing heat at the upper end of the heat exchange plate 1, and the liquid refrigerant flows along the descending channel to the lower end of the heat exchange plate 1 under the action of gravity, forming a refrigerant reflux. Thus, the high heat transfer capacity formed by the refrigeration evaporation-condensation cycle can achieve efficient heat exchange between the upper and lower regions of the battery cell 2, effectively reducing the overall temperature difference of the battery module 100. Compared with the scheme of setting one cooler 4 at the top and one at the bottom of the battery cell 2, this reduces the cost and weight of the battery module 100 and has a simpler structure.

[0180] This application also provides an electrical device, including a battery module 100 as described in any of the above embodiments.

[0181] Among them, electrical equipment can be vehicles, water heaters or other energy storage devices.

[0182] The electrical equipment provided in this application embodiment is equipped with the battery pack in the above embodiment, which can realize all the functions of the battery pack in the above embodiment, reduce the cost and weight of the battery module 100, and improve the safety and reliability of the electrical equipment.

[0183] In the technical solution of this application, the electrical equipment is a device or system that relies on electrical energy to work. The battery module 100 serves as the main power source for the electrical equipment and is connected to other parts of the electrical equipment through the output port to provide a stable and reliable power supply for the electrical equipment.

[0184] In addition to batteries, electrical equipment may also include other components or systems used to achieve its specific functions, such as control circuits, motors, and sensors, which are driven and controlled by electrical energy to realize the various functions of the electrical equipment.

[0185] It is understandable that electrical equipment uses batteries as its main source of power, which has advantages such as continuous power supply, good stability, high portability and energy saving and environmental protection, and is suitable for various equipment and systems that require electric power.

[0186] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0187] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0188] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0189] In the description of this application, "multiple" means two or more.

[0190] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them.

[0191] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0192] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0193] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A heat exchange plate, characterized in that, The heat exchange plate, disposed on the side of the battery cell, includes: refrigerant; A heat exchange channel is provided, wherein the refrigerant is disposed within the heat exchange channel, and the heat exchange channel includes an ascending channel and a descending channel that are connected end to end. When the temperature difference of the battery cell along the height direction is greater than a temperature threshold, the ascending channel is used to allow the refrigerant to pass through during or after evaporation, and the descending channel is used to allow the refrigerant to pass through during or after condensation. The heat exchange channel is annular, and the rising channel is formed along the first direction between the lowest point and the highest point of the inner ring outline of the heat exchange channel, and the falling channel is formed along the first direction between the highest point and the lowest point of the inner ring outline of the heat exchange channel, and the flow rate of the rising channel is smaller than that of the falling channel.

2. The heat exchange plate according to claim 1, characterized in that, The descending flow channel includes a first flow channel, a second flow channel, and a third flow channel connected in sequence, and the ascending flow channel includes a fourth flow channel and a fifth flow channel connected in sequence. The lower end of the first flow channel is connected to the upper end of the second flow channel, the lower end of the second flow channel is connected to the upper end of the third flow channel, the lower end of the third flow channel is connected to the lower end of the fourth flow channel, the upper end of the fourth flow channel is connected to the lower end of the fifth flow channel, and the upper end of the fifth flow channel is connected to the upper end of the first flow channel. The upper end of the fifth flow channel is higher than the upper end of the second flow channel along the direction of gravity.

3. The heat exchange plate according to claim 2, characterized in that, The second flow channel and the fifth flow channel extend along the direction of gravity; and / or, the flow area of ​​the fifth flow channel is greater than the flow area of ​​the second flow channel; and / or, the flow path of the rising flow channel is smaller than that of the falling flow channel.

4. The heat exchange plate according to claim 2, characterized in that, Satisfying: 0°<θ1≤25°, where θ1 is the inclination angle of the first flow channel relative to the horizontal direction; and / or, Satisfying: 0°<θ2≤45°, where θ2 is the inclination angle of the third flow channel relative to the horizontal direction; and / or, It satisfies: 0°<θ3≤45°, where θ3 is the inclination angle of the fourth flow channel relative to the horizontal direction.

5. The heat exchange plate according to claim 2, characterized in that, The cross-sectional area of ​​the fourth flow channel gradually increases from the end connected to the third flow channel to the end connected to the fifth flow channel; and / or, The cross-sectional area of ​​the first flow channel gradually increases from the end connected to the fifth flow channel to the end connected to the second flow channel.

6. The heat exchange plate according to claim 2, characterized in that, The first flow channel, the second flow channel, the third flow channel, and the fourth flow channel each include two sets. The two sets of the first flow channel, the two sets of the second flow channel, the two sets of the third flow channel, and the two sets of the fourth flow channel are symmetrically distributed on both sides of the fifth flow channel with the fifth flow channel as the axis of symmetry.

7. The heat exchange plate according to claim 2, characterized in that, The heat exchange channel also includes a sixth channel, which is disposed between the third channel and the fourth channel. The sixth channel extends horizontally and is close to the bottom end of the heat exchange plate along the direction of gravity.

8. The heat exchange plate according to claim 7, characterized in that, The fourth flow channel has a greater tilt angle to the horizontal direction than the third flow channel has to the horizontal direction.

9. The heat exchange plate according to claim 2, characterized in that, The heat exchange plate includes a first part and a second part, which together define the heat exchange channel. A first protrusion and a second protrusion are provided on the outer side of the first part and / or the outer side of the second part. The first protrusion and the second protrusion are arranged at intervals along the direction of gravity. The first protrusion and the second protrusion are used to connect with the battery cell.

10. The heat exchange plate according to claim 9, characterized in that, The first part and the second part are positioned and fitted together.

11. The heat exchange plate according to any one of claims 1-10, characterized in that, The heat exchange plate also includes a pressure relief valve, which is connected to the heat exchange channel.

12. The heat exchange plate according to any one of claims 1-10, characterized in that, The heat exchange plate is also provided with a thinning zone, which is located in the heat exchange channel.

13. A battery module, characterized in that, It includes a battery cell and a heat exchange plate as described in any one of claims 1-12, wherein the heat exchange plate is disposed on the side of the battery cell.

14. The battery module according to claim 13, characterized in that, It also includes a tray and a cooler, the cooler being disposed on top of the battery cell along the direction of gravity, the battery cell and the heat exchange plate being disposed on the tray, the top end of the heat exchange plate along the direction of gravity being close to the cooler, and the bottom end of the heat exchange plate along the direction of gravity being close to the bottom of the tray.

15. A battery pack, characterized in that, Includes the battery module as described in claim 13 or 14.

16. An electrical appliance, characterized in that, Includes the battery module as described in claim 13 or 14.

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