Liquid cooling plate runner for heat dissipation of battery pack and battery pack

Abstract

The utility model discloses a liquid cooling plate runner for heat dissipation of a battery pack and the battery pack, a cooling medium inlet is shunted to form a first inlet sub-runner and a second inlet sub-runner which are independent, and the first inlet sub-runner and the second inlet sub-runner are converged into a converging runner together and then are converged into a cooling medium outlet through a first outlet sub-runner and a second outlet sub-runner respectively; each sub-runner is designed to be a combination of different numbers of runner cavities from a single cavity to multiple cavities so as to regulate and control the flow and the flow speed of a cooling medium flowing through the sub-runners, and the number of the runner cavities in the first outlet sub-runner and the second outlet sub-runner is larger than that of the runner cavities in the first inlet sub-runner and the second inlet sub-runner. And the outlet side runner can distribute more fluid so as to ensure that the temperature difference of the battery pack is within a required range.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, and more specifically, to a liquid cooling plate flow channel and a battery pack for battery pack heat dissipation. Background Art

[0002] In the battery pack heat dissipation system, the heat dissipation efficiency of the liquid cooling plate is a key factor determining the battery performance and service life. The heat dissipation efficiency mainly depends on the temperature difference between the battery and the coolant, the contact area between the battery and the coolant, and the flow rate of the coolant passing through the battery. For a serial symmetric flow channel liquid cooling plate, the contact area between the battery and the coolant and the coolant flow rate are the same, and the heat generation of each battery is also the same. The temperature of the coolant will gradually increase along the serial flow channel. This gradually increasing temperature phenomenon will cause the temperature difference between the battery and the coolant to gradually decrease, thereby reducing the heat conduction efficiency. As the temperature of the coolant rises, its heat absorption capacity gradually weakens, resulting in a gradual increase in the highest temperature in the battery pack and an excessive overall temperature difference. This will not only affect the battery performance and efficiency but also shorten the battery service life and even may pose safety risks.

[0003] Figure 2 is a schematic diagram of a serial symmetric flow channel liquid cooling plate, Figure 3 is a schematic diagram of the simulation analysis result of the serial symmetric liquid cooling plate. From the result, the heat dissipation efficiency of the serial symmetric liquid cooling plate is poor, and the temperature difference between the inlet and outlet side batteries is large.

[0004] In order to achieve the ideal state where the temperature difference of the battery pack does not exceed 2°C and meet the existing requirements, it is necessary to solve the problem of excessive temperature difference of the coolant between the inlet and outlet sides of the serial symmetric liquid cooling plate. Summary of the Utility Model

[0005] Technical problem to be solved by the utility model: The purpose of the utility model is to overcome the deficiencies in the prior art and provide a liquid cooling plate flow channel for battery pack heat dissipation. By optimizing the flow channel design, the coolant can be more evenly distributed and flow in the flow channel, reducing the temperature gradient, so as to keep the temperature difference of the battery pack within a small range.

[0006] Technical solution: To achieve the above purpose, the technical solution provided by the utility model is as follows: It includes an upper liquid cooling plate and a lower liquid cooling plate. The upper liquid cooling plate is at the upper part, and the lower liquid cooling plate is attached to the bottom of the upper liquid cooling plate. The lower liquid cooling plate is provided with a flow channel for the cooling medium to flow. One end of the lower liquid cooling plate is arranged with a cooling medium inlet and a cooling medium outlet on the same side. The inlet side flow channel and the outlet side flow channel are respectively arranged on the cooling medium inlet and outlet sides, and are connected by a confluence flow channel in the middle. The inlet side flow channel and the outlet side flow channel are designed as a combination of different flow channel cavities from fewer cavities to more cavities to regulate the flow rate and velocity of the cooling medium flowing through the flow channel. The number of cavities of the outlet side flow channel is more than that of the inlet side.

[0007] The cooling medium inlet is divided into independent first and second inlet shunt channels. After confluence, they flow into the cooling medium outlet through the first and second outlet shunt channels. The number of flow channel cavities in the first and second outlet shunt channels is more than that in the first and second inlet shunt channels.

[0008] Furthermore, along the flow direction of the cooling medium, the first and second inlet shunt channels are designed to gradually increase from single-cavity channels to multi-cavity channels, and the first and second outlet shunt channels are designed to consist of multi-cavity channels.

[0009] Furthermore, the first inlet shunt channel is successively a single-cavity channel, a double-cavity channel, a triple-cavity channel, and a quadruple-cavity channel, and the second inlet shunt channel is successively a single-cavity channel, a double-cavity channel, and a triple-cavity channel; the first outlet shunt channel is successively a triple-cavity channel and a quadruple-cavity channel, and the second outlet shunt channel is all designed as a quadruple-cavity channel.

[0010] Another object of the present utility model is to provide a battery pack, which includes a plurality of groups of module batteries correspondingly placed on the inlet-side flow channel and the outlet-side flow channel, and each group of module batteries is correspondingly placed on the shunt channel on the cooling medium flow path.

[0011] For further limitation of the battery pack, the module batteries include a first row of module batteries, a second row of module batteries, a third row of module batteries, and a fourth row of module batteries correspondingly placed above the first inlet shunt channel, the second inlet shunt channel, the first outlet shunt channel, and the second outlet shunt channel along the flow direction of the cooling medium.

[0012] Furthermore, along the flow direction of the cooling medium, the front end of the first row of module batteries is cooled by a single-cavity channel, then cooled by a double-cavity channel, then cooled by a triple-cavity channel, and finally cooled by a quadruple-cavity channel and continues to the tail-end confluence channel; the front end of the second row of module batteries is cooled by a single-cavity channel, then cooled by a double-cavity channel, and the remaining batteries are cooled by a triple-cavity channel and continue to the tail-end confluence channel;

[0013] Furthermore, along the flow direction of the cooling medium, the third row of module batteries is successively cooled by a triple-cavity channel and a quadruple-cavity channel, and all the batteries of the fourth row of module batteries are cooled by a quadruple-cavity channel.

[0014] Beneficial effects: By adopting the technical solution provided by the present utility model, compared with the prior art, the following beneficial effects are achieved:

[0015] 1. A liquid cooling plate flow channel for battery pack heat dissipation provided by the present utility model takes into account the characteristic that the front-end batteries are greatly affected by the coolant temperature. The batteries on the inlet and outlet sides are arranged above different numbers of cavity flow channels. The temperature of the batteries near the inlet is lower than that of other battery areas. By reducing the number of flow channel cavities on the inlet side and increasing the number of flow channel cavities on the outlet side, the minimum temperature of the batteries on the inlet side is increased, and the maximum temperature of the batteries on the outlet side is reduced, ultimately achieving the purpose of minimizing the temperature difference of the battery pack.

[0016] 2. A liquid cooling plate flow channel for battery pack heat dissipation provided by the present utility model has a unique flow channel design, enabling the cooling medium to be more evenly distributed and flow in the flow channel, reducing the temperature gradient, and effectively reducing the temperature difference and temperature rise inside the battery pack.

[0017] 3. A battery pack provided by the present utility model has the temperature of the cooling medium gradually increasing during the flow process from the first row of module batteries to the fourth row of module batteries. By gradually increasing the number of cavity flow channels of the batteries, it can ensure that the batteries can still obtain sufficient cooling effect while the temperature of the cooling medium rises, improving the safety performance of the battery pack. Brief Description of the Drawings

[0018] Figure 1 It is a schematic structural diagram of the whole package in the liquid cooling plate flow channel structure for battery pack heat dissipation of the present utility model;

[0019] Figure 2 It is a schematic structural diagram of a serial symmetric liquid cooling plate;

[0020] Figure 3 It is a schematic diagram of the simulation analysis result of the serial symmetric liquid cooling plate;

[0021] Figure 4 It is a schematic structural diagram of the liquid cooling plate flow channel structure (asymmetric) for battery pack heat dissipation of the present utility model;

[0022] Figure 5 It is Figure 4 a schematic diagram of the simulation analysis result of the asymmetric liquid cooling plate structure in

[0023] Explanation of the reference numerals in the schematic diagrams:

[0024] Upper liquid cooling plate; 2. Lower liquid cooling plate; 21. Cooling medium inlet; 22. Cooling medium outlet; 23. Inlet side flow channel; 24. Outlet side flow channel; 231. First inlet shunt channel; 232. Second inlet shunt channel; 241. First outlet shunt channel; 242. Second outlet shunt channel; 3. Confluence flow channel; 4. Island-type double-chamber flow channel; 5. Module battery; 51. First row of module batteries; 52. Second row of module batteries; 53. Third row of module batteries; 54. Fourth row of module batteries. Detailed Embodiment

[0025] To further understand the content of the present utility model, the present utility model will be described in detail in conjunction with the accompanying drawings and specific embodiments.

[0026] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0027] In the description of the present utility model, the meaning of "several" is one or more, the meaning of "multiple" is two or more, and understandings such as "greater than", "less than", "exceeding", etc. do not include the present number, and understandings such as "above", "below", "within", etc. include the present number. If there is a description of "first" and "second", it is only for the purpose of distinguishing technical features and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0028] In the description of the present utility model, unless otherwise clearly defined, words such as "set", "installed", "connected", etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present utility model in combination with the specific content of the technical solution.

[0029] Such as Figures 1-5 , a liquid-cooled plate flow channel structure for battery pack heat dissipation, including an upper liquid-cooled plate 1 and a lower liquid-cooled plate 2. The upper liquid-cooled plate 1 is at the upper part, the lower liquid-cooled plate 2 is attached to the bottom of the upper liquid-cooled plate 1, and flow channels for the cooling medium to flow are provided on the lower liquid-cooled plate 2. After the upper and lower liquid-cooled substrates are joined together, each flow channel forms a mutually connected flow channel system.

[0030] Inlet and outlet water pipes are installed on the same side at one end of the upper liquid-cooled plate. The cooling medium flows in through the inlet pipe and out through the outlet pipe. Corresponding to the inlet and outlet water pipes are a cooling medium inlet 21 and a cooling medium outlet 22 arranged on the same side at one end of the lower liquid-cooled plate 2. The cooling medium flows into the inlet through the inlet pipe and finally flows out to the outlet pipe through the outlet. An inlet-side flow channel 23 is provided on the cooling medium inlet side, and an outlet-side flow channel 24 is provided on the cooling medium outlet side. The inlet-side flow channel 23 and the outlet-side flow channel 24 are arranged oppositely, but are of an asymmetric structure. The inlet-side flow channel 23 and the outlet-side flow channel 24 are connected by a confluence flow channel 3. The confluence flow channel 3 is arranged at the opposite end of the flow channel inlet and outlet to change the flow direction of the cooling medium. The cooling medium flows out from the end of the inlet-side flow channel 23 and then enters the confluence flow channel 3 to change the flow direction and then flows into the outlet-side flow channel 24 again, thereby completing the entire cooling cycle.

[0031] The inlet side flow channel 23 bifurcates at the cooling medium inlet to form two independent shunt channels, namely the first inlet shunt channel 231 and the second inlet shunt channel 232. Along the flow direction of the cooling medium, the first inlet shunt channel 231 is successively a single cavity flow channel, a double cavity flow channel, a triple cavity flow channel, and a quadruple cavity flow channel, and the second inlet shunt channel 232 is successively a single cavity flow channel, a double cavity flow channel, and a triple cavity flow channel. The tails of the quadruple cavity flow channel of the first inlet shunt channel 231 and the triple cavity flow channel of the second inlet shunt channel 232 merge into a common confluence flow channel 3.

[0032] The outlet side flow channel 24 also finally merges into the cooling medium outlet 22 through two independent shunt channels, which are respectively defined as the first outlet shunt channel 241 and the second outlet shunt channel 242. Along the flow direction of the cooling medium, the first outlet shunt channel 241 is successively a triple cavity flow channel and a quadruple cavity flow channel, and the second outlet shunt channel 242 is entirely designed as a quadruple cavity flow channel. The tails of the quadruple cavity flow channels of the first and second outlet shunt channels are connected to the cooling medium outlet 22 through an island-type double chamber flow channel 4, and the island-type double chamber flow channel 4 is a flow channel structure formed by a number of discontinuous islands.

[0033] Four rows of identical module batteries 5 are placed along the flow direction of the cooling medium on the liquid cooling plate. Each row of module batteries contains 13 batteries, which are defined here as the first row of module batteries 51, the second row of module batteries 52, the third row of module batteries 53, and the fourth row of module batteries 54. The first, second, third, and fourth rows of module batteries are successively placed side by side above the first inlet shunt channel 231, the second inlet shunt channel 232, the first outlet shunt channel 241, and the second outlet shunt channel 242 on the liquid cooling plate.

[0034] Along the flow direction of the cooling medium, the first battery of the first row of module batteries 51 is cooled by a single cavity flow channel, the second to third batteries are cooled by a double cavity flow channel, the fourth to ninth batteries are cooled by a triple cavity flow channel, and the tenth to thirteenth batteries are cooled by a quadruple cavity flow channel and continue to the tail end confluence flow channel; the first battery of the second row of module batteries 52 is cooled by a single cavity flow channel, the second to third batteries are cooled by a double cavity flow channel, and the fourth to thirteenth batteries are cooled by a triple cavity flow channel and continue to the tail end confluence flow channel 3.

[0035] The cooling medium converges at the ends of the first inlet shunt channel 231 and the second inlet shunt channel 232 on the inlet side, and enters the first outlet shunt channel 241 and the second outlet shunt channel 242 respectively through the converging flow channel 3. Along the flow direction of the cooling medium, the first to fourth cells of the third row of module batteries 53 are cooled by a three-cavity flow channel, and the fifth to thirteenth cells are cooled by a four-cavity flow channel and continue to the end island-type double-chamber flow channel 4. Along the flow direction of the cooling medium, all the cells of the fourth row of module batteries 54 are cooled by a four-cavity flow channel and continue to the end island-type double-chamber flow channel.

[0036] When the module batteries are cooled by using the above liquid cooling plate structure, the cooling medium enters through the cooling medium inlet 21, and after being shunted, it flows into the first inlet shunt channel 231 and the second inlet shunt channel 232 at the same time. The inlet side flow channel 23 will first dissipate heat from the first row of module batteries 51 and the second row of module batteries 52; because the temperature of the cooling medium on the inlet side is low, the number of flow channel cavities in the inlet side flow channel 23 should not be set too many, so as to control the contact area between the cooling medium and the battery and accelerate the flow rate of the cooling medium, thereby increasing the minimum temperature of the batteries on the inlet side and effectively controlling the temperature rise of the coolant.

[0037] The cooling medium that enters the first row of module batteries 51 and the second row of module batteries 52 converges into the converging flow channel 3 at the end, and finally flows into the first outlet shunt channel 241 and the second outlet shunt channel 242 respectively. The outlet side flow channel 24 dissipates heat from the third row of module batteries 53 and the fourth row of module batteries 54. At this time, the temperature of the cooling medium is higher than that on the inlet side, so the number of flow channel cavities of the outlet side liquid cooling plate is increased, so as to increase the contact area between the coolant and the battery and reduce the flow rate of the coolant passing through the battery, thereby reducing the maximum temperature of the batteries on the outlet side. By controlling the number of flow channel cavities in the inlet and outlet side shunt channels, the fluid flow rate and velocity are adjusted, and finally the temperature difference of the batteries in the battery pack is controlled not to exceed 2°C. And the number of flow channel cavities used by the batteries at different positions in each row of module batteries is different, and the heat dissipation of each battery is accurately controlled through this unique design of the shunt channel.

[0038] For this embodiment, the two outer flow channels are the first inlet shunt channel 51 and the second outlet shunt channel 54. The first inlet shunt channel 51 is designed as a single-cavity flow channel, a double-cavity flow channel, a three-cavity flow channel and a four-cavity flow channel in sequence, and the second outlet shunt channel 54 is all designed as a four-cavity flow channel, and is matched with the island-type double-chamber flow channel 4 at the same time. Since the path of the cooling medium to reach the second outlet shunt channel 54 is longer, the number of flow channel cavities provided in the second outlet shunt channel 54 is more than that of the first inlet shunt channel 51 to ensure the balance of battery cooling at the inlet and outlet.

[0039] The two flow channels in the inner ring are the second inlet shunt channel 52 and the first outlet shunt channel 53. The second inlet shunt channel 52 is designed as a single-chamber flow channel, a double-chamber flow channel, and a triple-chamber flow channel in sequence; the first outlet shunt channel 53 is designed as a triple-chamber flow channel and a quadruple-chamber flow channel in sequence, and at the same time cooperates with the island-type double-chamber flow channel 4. Similarly, the number of flow channel cavities set in the first outlet shunt channel 53 is also more than that in the second inlet shunt channel 52.

[0040] Thus, whether it is the outer ring flow channel or the inner ring flow channel, the number of flow channel cavities included in the shunt channel on the outlet side is more dense than that on the inlet side. This is because the path on the outlet side is long, and the temperature of the cooling medium will gradually increase as the path increases, resulting in too large a temperature difference between the inlet and outlet side batteries. Therefore, it is necessary to set more dense flow channel cavities on the corresponding flow channels on the outlet side.

[0041] Among the two shunt channels on the inlet side, the number of flow channel cavities in the first inlet shunt channel 51 is more dense than that in the second inlet shunt channel 52. Similarly, the number of flow channel cavities in the second outlet shunt channel 54 on the outlet side is more dense than that in the first outlet shunt channel 53. This density is reflected in the fact that the quadruple-chamber flow channels of the first inlet shunt channel and the second outlet shunt channel have greater fluid distribution capabilities, because the first inlet shunt channel 51 and the second outlet shunt channel 54 are located in the outer ring and have a longer path.

[0042] By designing flow channel cavities with different densities in the inlet and outlet side flow channels, a multi-level cooling system is realized. The shunt channel design follows the principle of combining flow channel cavities from single to multiple to adapt to the cooling requirements of batteries in different positions. By increasing the number of cavities in the outlet side and outer ring shunt channels, the contact area between the battery and the cooling medium and the medium flow rate are controlled, realizing fine regulation of battery heat dissipation, adjusting the cooling medium flow rate, thereby balancing the temperature uniformity of the entire battery pack module, increasing the lowest temperature of the inlet side battery, reducing the highest temperature of the outlet side battery, and finally achieving the purpose that the temperature difference of the battery pack does not exceed 2 degrees Celsius.

[0043] In order to compare with the cooling effect of the serial symmetric flow channel, the applicant conducted a simulation experiment on the asymmetric flow channel structure in this embodiment. As shown in the simulation results, the results show that the asymmetric flow channel is used to coordinate the effective contact area and effective contact time between the battery and the cooling medium, as well as the difference between the battery temperature and the temperature of the coolant flowing through the battery, thereby improving the consistency of the heat dissipation effect of single cells. It can be seen from the analysis results that the temperature difference of the battery pack does not exceed 2°C.

[0044] The above has schematically described the present utility model and its implementation manners. This description is not restrictive. What is shown in the drawings is only one of the implementation manners of the present utility model, and the actual structure is not limited thereto. Therefore, if those of ordinary skill in the art are inspired by it and, without departing from the gist of the creation of the present utility model, design similar structural manners and embodiments to this technical solution without creative efforts, they shall fall within the protection scope of the present utility model.

Claims

1. A liquid cooling plate flow channel for heat dissipation of a battery pack, comprising an upper liquid cooling plate (1) and a lower liquid cooling plate (2), wherein the upper liquid cooling plate (1) is at the top, and the lower liquid cooling plate (2) is attached to the bottom of the upper liquid cooling plate (1), and a flow channel for cooling medium to flow is provided on the lower liquid cooling plate (2), characterized in that: A cooling medium inlet (21) and a cooling medium outlet (22) are arranged on the same side of one end of the lower liquid cooling plate (2); an inlet side flow channel (23) and an outlet side flow channel (24) are respectively arranged on the cooling medium inlet (21) and the cooling medium outlet (22) sides, and are connected in the middle by a converging flow channel (3); the inlet side flow channel (23) and the outlet side flow channel (24) are designed to be a combination of different flow channel cavities from a small number of cavities to a large number of cavities to regulate the flow rate and flow velocity of the cooling medium flowing through the flow channel; the number of cavities of the outlet side flow channel (24) is greater than that of the inlet side; The cooling medium inlet (21) is split to form an independent first inlet branch flow channel (231) and a second inlet branch flow channel (232), and after merging, the flow channels are merged into the cooling medium outlet (22) through the first outlet branch flow channel (241) and the second outlet branch flow channel (242), and the number of flow channel cavities in the first outlet branch flow channel (241) and the second outlet branch flow channel (242) is greater than that in the first inlet branch flow channel (231) and the second inlet branch flow channel (232); Along the flow direction of the cooling medium, the first inlet branch flow channel (231) and the second inlet branch flow channel (232) are designed to gradually increase from a single-cavity flow channel to a multi-cavity flow channel, and the first outlet branch flow channel (241) and the second outlet branch flow channel (242) are designed to consist of a multi-cavity flow channel; The first inlet flow channel (231) is sequentially a single-cavity flow channel, a double-cavity flow channel, a three-cavity flow channel and a four-cavity flow channel, and the second inlet flow channel (232) is sequentially a single-cavity flow channel, a double-cavity flow channel and a three-cavity flow channel; the first outlet flow channel (241) is sequentially a three-cavity flow channel and a four-cavity flow channel, and the second outlet flow channels (242) are all designed to be four-cavity flow channels.

2. A battery pack, characterized in that: The liquid cooling plate flow channel as claimed in claim 1 comprises a plurality of groups of module batteries correspondingly placed on the inlet side flow channel (23) and the outlet side flow channel (24), and each group of module batteries is correspondingly placed on a branch flow channel on the cooling medium flow path.

3. The battery pack according to claim 2, characterized in that: The module battery comprises a first row of module batteries (51), a second row of module batteries (52), a third row of module batteries (53) and a fourth row of module batteries (54) which are placed above the first inlet shunt channel (231), the second inlet shunt channel (232), the first outlet shunt channel (241) and the second outlet shunt channel (242) respectively along the flow direction of the cooling medium.

4. The battery pack according to claim 3, characterized in that: Along the flow direction of the cooling medium, the front end of the first row of module batteries (51) is cooled by the single-cavity flow channel, then by the double-cavity flow channel, then by the triple-cavity flow channel, and finally by the quad-cavity flow channel and continues to the tail end converging flow channel (3); the front end of the second row of module batteries (52) is cooled by the single-cavity flow channel, then by the double-cavity flow channel, and the remaining batteries are cooled by the triple-cavity flow channel and continue to the tail end converging flow channel (3).

5. The battery pack according to claim 4, characterized in that: Along the flow direction of the cooling medium, the third row of module batteries (53) are cooled by the three-cavity flow channel and the four-cavity flow channel in sequence, and all batteries in the fourth row of module batteries (54) are cooled by the four-cavity flow channel.

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