A water-cooling system structure and power battery system suitable for batteries

Abstract

This utility model discloses a water-cooling system structure and a power battery system suitable for batteries, including a shunt pipe and a manifold pipe, with several water-cooling plates disposed between the shunt pipe and the manifold pipe; one end of each water-cooling plate is connected to the shunt pipe via an inlet pipe, and the other end is connected to the manifold pipe via an outlet pipe; the manifold pipe includes a return water pipe and a connecting pipe, with a first connection port and a second connection port on both ends of the connecting pipe, the first connection port communicating with one end of the return water pipe, and the second connection port communicating with the other end of the return water pipe; the connecting pipe is provided with a baffle structure for isolating the liquid flow in the connecting pipe, the baffle structure being located between the first connection port and the second connection port and adjacent to the second connection port; the bottom end of the shunt pipe is connected to an inlet pipe with a quick-connect water inlet connector, and the bottom end of the manifold pipe is connected to an outlet pipe with a quick-connect water outlet connector. This solves the problem of large temperature differences and high temperatures in existing locomotive battery water-cooling systems, which directly affect the battery system's lifespan.

Description

Technical Field

[0001] This utility model relates to the field of battery cooling technology, and the batteries include, but are not limited to, power battery systems or backup battery systems for locomotives or EMUs, and particularly to a water cooling system structure and power battery system suitable for batteries. Background Technology

[0002] As the power source or backup power for locomotives or EMUs, the safety, reliability, and lifespan of the battery system directly affect the vehicle's safety, reliability, and lifespan. The battery's temperature characteristics, including its maximum temperature and temperature uniformity, directly impact its safety, reliability, and lifespan. The cooling system's task is to maintain the battery temperature at a suitable level. Water-cooling systems, with their high heat exchange capacity, are suitable for battery cooling.

[0003] Currently, the locomotive battery water cooling system is a series system, which will result in a large temperature difference and high temperature in the battery system, and cannot effectively cool the battery, thus directly affecting the service life of the battery system. Summary of the Invention

[0004] This invention provides a water-cooling system structure and a power battery system suitable for batteries, in order to overcome the above-mentioned technical problems.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] A water-cooling system structure suitable for batteries includes a shunt pipe and a manifold pipe, and a plurality of water-cooling plates are provided between the shunt pipe and the manifold pipe at intervals.

[0007] One end of each water-cooled plate is connected to a branch pipe via an inlet pipe, and the other end is connected to a manifold via an outlet pipe; the top of the branch pipe and the manifold are equipped with automatic air vent valves.

[0008] The manifold includes a return water pipe and a manifold, and a first connection port and a second connection port are provided at both ends of the manifold. The first connection port is connected to one end of the return water pipe, and the second connection port is connected to the other end of the return water pipe.

[0009] The manifold is provided with a baffle structure for isolating the flow of liquid in the manifold, and the baffle structure is located between the first connection port and the second connection port and adjacent to the second connection port. The bottom end of the branch pipe is connected to an inlet pipe with a quick inlet connector, and the bottom end of the manifold is connected to an outlet pipe with a quick outlet connector.

[0010] Furthermore, the side wall of the diversion pipe is provided with several inlet pipe connections at equal intervals, and the side wall of the manifold is provided with several outlet pipe connections at equal intervals, with the inlet pipe connections and outlet pipe connections being arranged parallel to each other.

[0011] Furthermore, both the inlet and outlet pipes are made of rubber hoses, and the planes where the inlet and outlet pipe connections are located are above the planes where the water-cooling plates corresponding to the inlet and outlet pipe connections are located.

[0012] Furthermore, the inlet pipe connection is connected to a diverter, and the outlet pipe connection is connected to a manifold; the inlet pipe is connected to the diverter pipe via the diverter, and the outlet pipe is connected to the manifold via the manifold.

[0013] Furthermore, the water-cooling plate is made of aluminum alloy, the battery is placed on the top of the water-cooling plate, and a thermally conductive structural adhesive filling layer is provided between the bottom surface of the battery and the top surface of the water-cooling plate.

[0014] Furthermore, the branch pipe and the manifold are arranged vertically and parallel to each other.

[0015] A power battery system, the power battery system including the water cooling system structure as described above.

[0016] Beneficial Effects: This utility model provides a water-cooling system structure and power battery system suitable for batteries, including a shunt pipe and a manifold pipe, with several water-cooling plates spaced apart between the shunt pipe and the manifold pipe; one end of each water-cooling plate is connected to the shunt pipe through an inlet pipe, and the other end is connected to the manifold pipe through an outlet pipe. By connecting the water paths of each water-cooling plate in the water-cooling system in parallel and using a bottom-inlet and bottom-outlet water-cooling method, the battery is cooled down. At the same time, the inlet pipe and outlet pipe are set as rubber hoses, and the shunt pipe is connected to the shunt connector through the inlet pipe connection port set on the side wall of the shunt pipe, and the outlet pipe set on the side wall of the manifold pipe is connected to the manifold connector, so as to ensure that the coolant flow rate in each water-cooling plate is the same, which can improve the temperature uniformity of the battery system, greatly reduce the maximum temperature of the battery system, and thus improve the service life of the battery. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the water-cooling system structure applicable to batteries according to this utility model;

[0019] Figure 2 This is a schematic diagram of the shunt pipe in this embodiment;

[0020] Figure 3This is a schematic diagram of the manifold structure in this embodiment;

[0021] Figure 4 This is a front view of the water-cooling system structure applicable to the battery in this embodiment;

[0022] Figure 5 This embodiment shows a schematic diagram of the flow rate of each water-cooled plate obtained based on the flow matching simulation calculation results under the set flow rate conditions.

[0023] Figure 6 This is a simulation diagram of the battery pack temperature distribution under the maximum and minimum coolant flow conditions in this embodiment.

[0024] In the diagram: 1. Diverter pipe; 10. Diverter connector; 11. Inlet pipe connection; 2. Manifold pipe; 12. Outlet pipe connection; 21. Return pipe; 22. Manifold pipe; 221. First connection port; 222. Second connection port; 223. Manifold connector; 23. Baffle structure; 3. Water-cooled plate; 4. Inlet pipe; 5. Outlet pipe; 6. Automatic air vent valve; 7. Inlet pipe; 8. Outlet pipe. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] This embodiment provides a water-cooling system structure suitable for batteries, such as Figure 1 and Figure 4 As shown, it includes a vertically and parallelly arranged branch pipe 1 and a manifold 2, with several water-cooled plates 3 spaced apart between the branch pipe 1 and the manifold 2;

[0027] Specifically, such as Figure 2 As shown, a plurality of water inlet pipe connections 11 are provided at equal intervals on the side wall of the diversion pipe 1, and a plurality of water outlet pipe connections 12 are provided at equal intervals on the side wall of the manifold 22, with the water inlet pipe connections 11 and the water outlet pipe connections 12 arranged parallel to each other.

[0028] One end of each water-cooled plate 3 is connected to the branch pipe 1 via the water inlet pipe 4, and the other end is connected to the manifold 2 via the water outlet pipe 5; the top of the branch pipe 1 and the manifold 2 are equipped with an automatic air vent valve 6;

[0029] like Figure 3As shown, the manifold 2 includes a return water pipe 21 and a manifold 22, and a first connection port 221 and a second connection port 222 are provided on both ends of the manifold 22. The first connection port 221 is connected to one end of the return water pipe 21, and the second connection port 222 is connected to the other end of the return water pipe 21.

[0030] The manifold 22 is provided with a baffle structure 23 for isolating the flow of liquid in the manifold 22. The baffle structure 23 is located between the first connection port 221 and the second connection port 222 and is adjacent to the second connection port 222. The baffle structure 23 can ensure that the coolant flows out from the top of the manifold 22 and flows out into the return water pipe 21, so that the coolant can ensure sufficient residence time and cool down the heat generated by the battery. The bottom end of the branch pipe 1 is connected to the water inlet pipe 7 with a quick water inlet connector, and the bottom end of the manifold 2 is connected to the water outlet pipe 8 with a quick water outlet connector.

[0031] Specifically, both the inlet and outlet quick connectors are self-sealing quick-connect connectors. When the quick connector is connected to the external water supply pipeline of the battery cabinet, the internal flow path of the quick connector automatically opens; when the quick connector is disconnected from the external water supply pipeline of the battery cabinet, the internal flow path of the quick connector automatically closes, ensuring no liquid leakage. In addition, the inlet pipe 7 and the outlet pipe 8 are a combination structure of rubber hose, stainless steel seamless steel pipe, connector components and sealing ring, etc. The specific structural composition of the inlet pipe 7 and the outlet pipe 8 is based on existing technology and will not be described in detail here.

[0032] Specifically, both the inlet pipe 4 and the outlet pipe 5 are made of rubber hoses. The planes where the inlet pipe connection port 11 and the outlet pipe connection port 12 are located are above the planes where the water-cooled plate 3, which is connected to the corresponding inlet pipe 4 and outlet pipe 5, is located. In this embodiment, the joints connecting the inlet pipe 4, the outlet pipe 5, and the water-cooled plate 3 are self-sealing quick connectors: when the self-sealing quick connector is connected, the internal flow path of the self-sealing quick connector is automatically opened; when the self-sealing quick connector is disconnected, the internal flow path of the self-sealing quick connector is automatically disconnected, ensuring no leakage of coolant. This allows each water-cooled plate to be disassembled individually without draining coolant from the water-cooling system, facilitating maintenance.

[0033] Specifically, the inlet pipe connection 11 is connected to a diverter 10, and the outlet pipe connection 12 is connected to a manifold 223; the inlet pipe 4 is connected to the diverter pipe 1 through the diverter 10, and the outlet pipe 5 is connected to the manifold 22 through the manifold 223.

[0034] In this embodiment, the design method for the internal flow cross-sectional area of ​​the manifold 223 and the branch connector 10 is as follows: Based on computational fluid dynamics, the coolant flow rate of each water-cooled plate in the water-cooling system is calculated. According to the calculated coolant flow rate, the coolant flow rate of the branch connector or return connector is adjusted to finely adjust the flow rate of each water-cooled plate. Specifically, this includes:

[0035] S10: Based on computational fluid dynamics methods and using CFD software (such as, but not limited to, FloEFD), calculate and obtain the coolant flow rate of each water-cooled plate in the water-cooling system structure. The goal is to ensure that the coolant flow rate of each water-cooled plate is basically the same (i.e., the relative deviation of coolant flow rate between water-cooled plates is less than 10%). Specifically, this includes the following steps:

[0036] S100: Based on 3D modeling software (such as, but not limited to, UG NX 8.0), a 3D model of the fluid domain is established according to the structure of the water cooling system;

[0037] S101: Set the boundary conditions for the fluid domain, which include:

[0038] The solid wall is a no-slip boundary condition: u wall = 0, where u represents the fluid velocity of the coolant, and wall represents the wall position of the water-cooled plate; the water inlet is a velocity boundary condition: u inlet = u0, where u represents the fluid velocity of the coolant, inlet represents the water inlet, u0 represents the magnitude of the inlet velocity, and its direction is perpendicular to the inlet surface and points in the direction of fluid flow; the water outlet is a pressure boundary condition: p outlet =p0, where p represents the fluid pressure of the coolant, outlet represents the water outlet, and p0 represents the outlet pressure.

[0039] S102: Set the fluid domain physical model based on the fluid domain boundary conditions; its expression is as follows:

[0040]

[0041] In the formula: ρ represents the velocity vector of the fluid flow inside the water-cooled plate; p represents the fluid density inside the water-cooled plate; μ represents the fluid viscosity. t ε represents the turbulent viscosity; k represents the turbulent kinetic energy of the fluid; ε represents the turbulent dissipation rate of the fluid. The divergence operator for vectors or the gradient operator for scalars; Represents the Laplace operator; C μ This represents an empirical constant, typically with a value of 0.09.

[0042] S103: Calculate and obtain the velocity field of the fluid domain through the fluid domain physical model;

[0043] Furthermore, the velocity field of the fluid domain includes at least the average fluid velocity at the inlet or outlet section of the water-cooled plate;

[0044] S104: Obtain the coolant flow rate of the water-cooled plate based on the velocity field of the fluid domain: that is, the product of the average fluid velocity at the inlet or outlet section of the water-cooled plate and the cross-sectional area at the inlet or outlet of the water-cooled plate.

[0045] S105: Based on S104, obtain the coolant flow rate of each water-cooled plate, and compare the coolant flow rate of any water-cooled plate with the expected coolant flow rate.

[0046] If the coolant flow rate is greater than the expected coolant flow rate, then according to experience, the coolant flow rate of the corresponding water-cooled plate is reduced by decreasing the internal flow cross-sectional area of ​​the manifold or return pipe.

[0047] If the coolant flow rate is equal to the desired coolant flow rate, then keep the internal flow cross-sectional area of ​​the corresponding shunt or return pipe joint connected to the water-cooled plate unchanged.

[0048] If the coolant flow rate is less than the desired coolant flow rate, then according to experience, the coolant flow rate of the corresponding water-cooled plate can be increased by increasing the internal flow cross-sectional area of ​​the manifold or return pipe.

[0049] S106: Based on S105, confirm the internal flow cross-sectional area of ​​the corresponding shunt pipe joint or return pipe joint of each water-cooled plate, and then design and obtain the internal diameter of each shunt pipe joint or return pipe joint.

[0050] In this embodiment, the flow resistance of each branch can be adjusted by reducing the coolant flow rate of the branch connector or manifold, thereby adjusting the coolant flow rate of each water-cooled plate. Similarly, if the structural dimensions allow, increasing the coolant flow rate of the branch connector or manifold can also adjust the flow resistance of each branch, thereby adjusting the coolant flow rate of each water-cooled plate. Furthermore, the internal diameter of each branch connector or return connector can be confirmed through simulation, thus completing the design of the structural parameters of the water-cooling system. Figure 5 As shown, the minimum flow rate of the water-cooled plate is 0.0267 kg / s, the maximum flow rate of the water-cooled plate is 0.0279 kg / s, and the relative deviation between the maximum and minimum flow rates is 4.49%.

[0051] S20: Battery system temperature distribution under characteristic operating conditions: This involves calculating the battery system temperature distribution after finely adjusting the flow rates of each water-cooled plate, specifically including the following steps:

[0052] S201: Determine the battery heat generation power: Determine the worst operating conditions when the battery is cooled, i.e., the operating conditions with the highest ambient temperature and the highest charge / discharge rate, and take this as the characteristic operating condition; obtain the heat generation power of the battery cell under the characteristic operating condition based on the characteristic operating condition and the battery parameters provided in advance by the battery manufacturer, or through the pre-set test method.

[0053] S202: Establish a 3D thermal simulation model, including water-cooled pipes, water-cooled plates, coolant, thermal pads, and batteries. If the influence of environmental conditions such as solar radiation on battery temperature needs to be considered, a more detailed 3D model is required, including the battery cabinet and the air space between the battery cabinet and the battery. The more complex the 3D model, the more computer resources and computation time are required for numerical calculations. To save computational resources and time, simplification and equivalence processing can be performed. For example, external heat sources such as solar radiation can be treated as internal heat sources and directly applied to the battery geometric model, which simplifies the process of establishing the 3D model. The method for establishing the 3D thermal simulation model in this embodiment is a known existing technology and will not be described in detail here.

[0054] S203: Set the boundary conditions for simulation calculations, including fluid domain inlet and outlet boundary conditions, solid thermal boundary conditions, etc. Specifically, existing CFD software (such as Flo EFD) has this boundary condition selection option, and you only need to select the required boundary condition selection.

[0055] S204: Set the physical model, which includes the fluid domain physical model, the solid domain physical model, physical property parameters, etc. Specifically, existing CFD software (such as Flo EFD) has options for physical models or physical property parameters such as three-dimensional, steady, constant density, and viscous fluid. Just select the option you need.

[0056] S205: Calculate the battery temperature to obtain the highest temperature T of the battery system. max The expression for the temperature difference ΔT between the battery system and the battery system is:

[0057]

[0058] In the formula: Q represents the heat power of the heat source; k represents the thermal conductivity of the battery; This represents the Laplace operator; T represents the battery temperature; in this embodiment, S20 enables the acquisition of the battery system's temperature distribution under calculated characteristic operating conditions. For example... Figure 6 As can be seen from the figure, Figure 6 (a) The temperature range of the batteries in the battery pack is 45.12℃~46.92℃ under the condition of minimum coolant flow rate; Figure 6(b) Under the condition of maximum coolant flow, the temperature range of the battery in the battery pack is 45.12℃~46.88℃, of which the highest battery temperature is 46.92℃ and the temperature difference of the battery system is 1.8℃;

[0059] Specifically, the water-cooled plate 3 is made of aluminum alloy. The battery is placed on top of the water-cooled plate 3, and a thermally conductive structural adhesive filling layer is provided between the bottom surface of the battery and the top surface of the water-cooled plate 3 to ensure the heat generated by the battery is conducted to the water-cooled plate 3. In this embodiment, the purple-red automatic vent valve 6 is installed on the top of the distributor pipe 1 and the manifold pipe 2 and connected to it. The automatic vent valve 6 has a nut structure at its upper end and a float mechanism inside. When the nut is loosened, if there is air in the distributor pipe 1 or the manifold pipe 2, the float will descend, and the air in the distributor pipe 1 or the manifold pipe 2 can be discharged from the nut of the automatic vent valve. After the air is discharged, the coolant will fill the automatic vent valve 6, and the float will rise, blocking the vent micro-hole at the top of the automatic vent valve 6, ensuring that the coolant will not overflow from the automatic vent valve 6.

[0060] This embodiment also includes a power battery system, which comprises the water-cooling system structure as described above. The water-cooling system structure serves as a core component for cooling the battery.

[0061] The water-cooling system structure described in this embodiment includes a distribution pipe and a manifold, with each water-cooling plate stacked vertically. The water channels of each water-cooling plate are connected in parallel, and the water inlet and outlet are arranged in a bottom-in, bottom-out manner. The inlet and outlet pipes are made of flexible rubber hoses, connected to a distribution connector via an inlet port on the side wall of the distribution pipe, and to a manifold connector via an outlet port on the side wall of the manifold, ensuring that the coolant flow rate in each water-cooling plate is essentially the same. Automatic air vents are installed at the top of the distribution pipe and manifold to remove air from the water pipes. Based on a calculation... Computational fluid dynamics methods are used to calculate the coolant flow rate of each water-cooled plate in the water-cooling system. Based on the calculated coolant flow rate, the internal cross-sectional area of ​​the shunt or manifold connectors is adjusted to finely adjust the coolant flow rate in each water-cooled plate. Finally, after finely adjusting the flow rate, the temperature distribution of the battery system under characteristic operating conditions is calculated, thereby obtaining the maximum temperature and temperature difference of the battery system to verify the performance of the water-cooling system structure. The water-cooling system structure described in this embodiment can improve the temperature uniformity of the battery system, greatly reduce the maximum temperature of the battery system, and thus improve the battery's service life.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A water-cooling system structure suitable for batteries, characterized in that, It includes a branch pipe (1) and a manifold (2), and several water-cooled plates (3) are provided between the branch pipe (1) and the manifold (2); One end of each water-cooled plate (3) is connected to the branch pipe (1) through the water inlet pipe (4), and the other end is connected to the manifold (2) through the water outlet pipe (5); the top of the branch pipe (1) and the manifold (2) are equipped with an automatic air vent valve (6); The manifold (2) includes a return water pipe (21) and a manifold (22), and a first connection port (221) and a second connection port (222) are provided on both ends of the manifold (22). The first connection port (221) is connected to one end of the return water pipe (21), and the second connection port (222) is connected to the other end of the return water pipe (21). The manifold (22) is provided with a baffle structure (23) for isolating the flow of liquid in the manifold (22), and the baffle structure (23) is located between the first connection port (221) and the second connection port (222) and adjacent to the second connection port (222). The bottom end of the branch pipe (1) is connected to the water inlet pipe (7) with a quick water inlet connector, and the bottom end of the manifold (2) is connected to the water outlet pipe (8) with a quick water outlet connector.

2. The water-cooling system structure suitable for batteries according to claim 1, characterized in that, The side wall of the diversion pipe (1) is provided with several inlet pipe connections (11) at equal intervals, and the side wall of the confluence pipe (22) is provided with several outlet pipe connections (12) at equal intervals, and the inlet pipe connections (11) and outlet pipe connections (12) are arranged parallel to each other.

3. The water-cooling system structure suitable for batteries according to claim 2, characterized in that, Both the inlet pipe (4) and the outlet pipe (5) are made of rubber hoses. The plane where the inlet pipe connection port (11) and the outlet pipe connection port (12) are located is above the plane where the water-cooled plate (3) is connected to the corresponding inlet pipe (4) and outlet pipe (5).

4. The water-cooling system structure suitable for batteries according to claim 3, characterized in that, The inlet pipe connection (11) is connected to a diverter (10), and the outlet pipe connection (12) is connected to a manifold (223); the inlet pipe (4) is connected to the diverter pipe (1) through the diverter (10), and the outlet pipe (5) is connected to the manifold (22) through the manifold (223).

5. The water-cooling system structure suitable for batteries according to claim 4, characterized in that, The water-cooled plate (3) is made of aluminum alloy. The battery is placed on the top of the water-cooled plate (3), and a thermally conductive structural adhesive filling layer is provided between the bottom surface of the battery and the top surface of the water-cooled plate (3).

6. The water-cooling system structure suitable for batteries according to claim 5, characterized in that, The shunt pipe (1) and the manifold pipe (2) are arranged vertically and parallel to each other.

7. A power battery system, characterized in that, The power battery system includes the water-cooling system structure as described in any one of claims 1 to 6.

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