A power battery cooling plate structure and a working method thereof

Abstract

The application discloses a power battery cooling plate structure and a working method thereof. The power battery cooling plate structure is arranged between a bottom plate and a bottom shell of a battery pack. The bottom plate is connected to the bottom surface of the main shell frame of the protective battery module through bolts. The top surface of the bottom plate is integrally provided with an upper partition plate, and the upper partition plate is limited around the battery module. The bottom surface of the bottom plate is integrally provided with a lower heat dissipation plate, and a plurality of lower heat dissipation plates are arranged in parallel along the length direction of the bottom plate. The air duct is formed between adjacent lower heat dissipation plates. The side walls of the bottom shell towards the vehicle head and tail are both provided with ventilation openings, and the two ports of the air duct are towards the ventilation openings. The battery module is cooled by the convection air cooling mode, and the cost is low and the cooling effect is good.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power battery cooling, in particular to a power battery cooling plate structure and a working method thereof. BACKGROUND

[0002] In the use process of the power battery of a new energy electric vehicle, a large amount of heat is generated. When the temperature of the power battery is too high, the resistance on the related conductor is increased, resulting in the conversion of electric energy into heat loss and reducing the efficiency of the battery. In addition, the high temperature may also cause the power battery to be out of control, thereby causing a safety hazard. Therefore, the power battery must be cooled.

[0003] The cooling system of the power battery mainly includes the following types: 1. Natural cooling, which relies on the rise and fall of the ambient temperature to achieve heat dissipation, and is cooled by air flow sweeping the outer wall of the shell. It is a passive and energy-saving solution, which is suitable for low cooling demand. 2. Air cooling: heat is taken away by air flow. Active air cooling is achieved by a fan to encourage air to flow through the cooling air duct, enhancing the cooling effect and providing more precise control. 3. Liquid cooling: liquid is used as a heat exchange medium, and its multi-path heat exchange circuit design gives it flexibility and high efficiency. The liquid cooling system is composed of a radiator, a compressor, an electric water pump, an evaporator, a cooling liquid, a fan, a temperature regulating device, a water pipe and an expansion tank. The cooling liquid is a mixture of water and ethylene glycol, which takes away heat through forced circulation of the cooling liquid. Liquid cooling technology has become the mainstream choice due to its excellent cooling performance, flexible adaptability and reliable stability. 4. Direct cooling: the refrigerant is directly introduced into the battery pack and directly contacts the battery shell for heat exchange. The direct cooling system has the characteristics of high efficiency, uniform cooling and fast response.

[0004] The third and fourth cooling systems are often used for more advanced electric vehicles, which can achieve good cooling effect, but such cooling systems also increase the manufacturing cost and reduce the price competitiveness. For low-end vehicles, if the active air cooling method is used, the fan and the side air duct assembly still need to be invested, which not only increases the equipment investment cost but also consumes part of the electric energy, and cannot achieve the best combination of cost and economy.

[0005] In order to overcome the above problems, a power battery cooling plate structure and a working method thereof are needed. SUMMARY

[0006] The purpose of the present application is to provide a power battery cooling plate structure and a working method thereof, which uses a convection air cooling method to cool the battery module, has low cost and good cooling effect.

[0007] To solve the above technical problems, the present application adopts the following technical scheme:

[0008] The application discloses a power battery cooling plate structure which is arranged between a bottom plate and a bottom shell of a battery pack, the bottom plate is connected to the bottom surface of a main shell frame of a protection battery module through bolts, the top surface of the bottom plate is integrally provided with an upper partition plate, and the upper partition plate is limited around the battery module; the bottom surface of the bottom plate is integrally provided with a plurality of lower heat dissipation plates which are arranged in parallel along the length direction of the bottom plate; air ducts are formed between adjacent lower heat dissipation plates; the side walls of the bottom shell towards the vehicle head and the vehicle tail are each provided with a ventilation opening, and the two ports of the air ducts are towards the ventilation openings.

[0009] Further, the battery module, the upper partition plate and the top surface of the bottom plate are provided with a silica gel plate with good heat conduction performance.

[0010] Further, a filter screen is further arranged on the inner side wall of the ventilation opening.

[0011] Further, the bottom shell is integrally provided with a clamping groove on the inner side wall of the ventilation opening at both the upper end and the lower end, and the filter screen is detachably arranged in the clamping groove.

[0012] Further, the cross section of the lower heat dissipation plate is a bent plate, and the distance between the lower heat dissipation plate and the bottom surface of the bottom shell is 2-5 mm.

[0013] Further, along the longitudinal center surface of the bottom shell, the bending directions of the lower heat dissipation plates on both sides are opposite.

[0014] Further, a heat dissipation film is further attached to the outer wall of the lower heat dissipation plate, and the heat dissipation film can be moisturized and evaporated to refrigerate.

[0015] Further, a spraying pipe and a spraying cavity are further arranged, the spraying cavity is arranged at one end of the bottom shell towards the vehicle head, and the spraying pipe is arranged at the top of the spraying cavity.

[0016] Further, the spraying pipe is fixedly connected to the top surface of the bottom plate along the width direction of the battery pack, a plurality of nozzles are equidistantly arranged on the bottom wall of the spraying pipe and protrude into the spraying cavity, and one end of the spraying pipe protrudes out of the outer wall of the main shell frame and is provided with a pipe joint connected to a water source.

[0017] The application further discloses a working method of the power battery cooling plate structure, and the battery module is used to dissipate heat, the partition plate around the battery module is used to guide heat downwards and is cooled by the convection wind in the process of vehicle driving.

[0018] Compared with the prior art, the application has the following beneficial technical effects:

[0019] The power battery cooling plate structure of the present invention divides the original enclosed chamber into an upper equipment sealing chamber and a lower cooling chamber through a bottom plate, which facilitates cooling by convection wind passing through the cooling chamber without affecting the sealing performance of the equipment; through the arrangement of the upper partition, the four sides and bottom surface of the battery module are in contact with the bottom plate, which facilitates the downward conduction of heat emitted by the battery module; through the parallel arrangement of multiple lower heat dissipation plates on the bottom plate, multiple air ducts of uniform size are formed, which facilitates the uniform guidance of convection wind and improves the cooling effect; the upper partition and the lower heat dissipation plates are both integrally arranged on the bottom plate, which not only improves the supporting strength of the bottom plate but also improves the thermal conductivity efficiency. The power battery cooling plate structure of the present invention and its working method adopt convection air cooling to achieve cooling of the battery module, which is low in cost and has a relatively good cooling effect.

[0020] Furthermore, the addition of a silicone plate fills the gap between the battery module and the base shell, acting as a buffer while also increasing the contact area between the two and improving thermal conductivity. A filter screen is added to the inner wall of the vent to provide coarse filtration of the convective air, preventing debris from entering and blocking the air duct. The use of a slot for mounting the filter screen facilitates its removal and replacement. The lower heat sink is designed as a folded plate, increasing the heat dissipation area while also allowing it to deform in the direction of the fold when the bottom shell is accidentally impacted, acting as a buffer and reducing the impact damage to the battery compartment. A spray chamber and spray pipe are provided at the end of the bottom shell facing the front of the vehicle, providing humidification at the air inlet. The moisture contacts the rear heat dissipation diaphragm, improving heat dissipation. The atomizing nozzle allows moisture to flow backward with the convective air, improving the overall moisture absorption efficiency of the heat dissipation diaphragm and preventing water accumulation within the bottom shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the front structure of a battery pack with a power battery cooling plate structure of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the top view of the battery pack with the upper shell removed;

[0024] Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure of the AA part;

[0025] Figure 4 for Figure 2 Schematic diagram of the cross-sectional structure of the middle BB part;

[0026] Figure 5 for Figure 3Schematic diagram of the locally enlarged structure of part I in the middle.

[0027] Explanation of the accompanying drawings: 1. Main shell frame; 101. Mounting claw plate; 2. Bottom shell; 201. Ventilation port; 3. Upper shell; 4. Battery module; 5. Bottom plate; 501. Upper partition; 502. Lower heat sink; 6. Air duct; 7. Spray chamber; 8. Filter; 9. Spray pipe; 901. Nozzle; 902. Pipe joint; 10. Silicone pad; 11. Heat dissipation diaphragm. DETAILED DESCRIPTION

[0028] The core of the present invention is to provide a power battery cooling plate structure and a working method thereof, which adopts convection air cooling to cool the battery module, with low cost and better cooling effect.

[0029] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0031] With reference to the accompanying drawings, Figure 1 This is a schematic diagram of the front structure of a battery pack with a power battery cooling plate structure of the present invention; Figure 2 for Figure 1 Schematic diagram of the top view of the battery pack with the upper shell removed; Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure of the AA part; Figure 4 for Figure 2 Schematic diagram of the cross-sectional structure of the middle BB part; Figure 5 for Figure 3 Schematic diagram of the locally enlarged structure of part I in the middle.

[0032] In one embodiment, Figures 1 to 5As shown, the main purpose of the power battery cooling plate structure of the present application is to improve the existing battery pack which lacks cooling structure, improve its cooling performance without significantly increasing the cost, and is suitable for low-end electric vehicle power battery application. The battery pack generally includes a closed chamber composed of a main shell frame 1, a bottom shell 2 and an upper shell 3, and a BMS, a battery module 4 and a wire harness arranged in the closed chamber. The main shell frame 1 is a profile steel frame which serves to enclose and protect the battery module 4. The power battery cooling plate structure of the present application is arranged between the bottom plate 5 and the bottom shell 2 of the battery pack, and the bottom plate 5 is connected to the bottom surface of the main shell frame 1 which protects the battery module 4 by bolts, that is, the bottom plate 5 divides the original closed chamber into an upper equipment sealing cavity and a lower cooling cavity. The bottom plate 5 is made of high-quality stainless steel plate. The top surface of the bottom plate 5 is integrally provided with an upper partition plate 501, and the upper partition plate 501 is limited around the battery module 4. The bottom surface of the bottom plate 5 is integrally provided with a lower heat dissipation plate 502, and a plurality of lower heat dissipation plates 502 are arranged in parallel along the length direction of the bottom plate 5. The adjacent lower heat dissipation plates 502 form an air duct 6. The side walls of the bottom shell 2 towards the front and rear of the vehicle are both provided with ventilation openings 201, the two ports of the air duct 6 are towards the ventilation openings 201, and the ventilation openings 201 are exposed below the vehicle chassis.

[0033] The original closed chamber is divided into an upper equipment sealing cavity and a lower cooling cavity by the bottom plate 5, which does not affect the equipment sealing performance, facilitates cooling by the convection wind through the cooling cavity; through the arrangement of the upper partition plate 501, the four sides and the bottom surface of the battery module 4 are in contact with the bottom plate 5, which facilitates the downward conduction of the heat emitted by the battery module 4; a plurality of lower heat dissipation plates 502 are arranged in parallel on the bottom surface of the bottom plate 5, forming a plurality of air ducts 6 with the same size, which facilitates uniform convection wind guidance and improves the cooling effect; the upper partition plate 501 and the lower heat dissipation plate 502 are integrally arranged on the bottom plate 5, which can not only improve the supporting strength of the bottom plate 5 but also improve the heat conduction efficiency. The power battery cooling plate structure and the working method thereof adopt the convection wind cooling mode to cool the battery module, which is low in cost and good in cooling effect.

[0034] In a specific embodiment of the present application, as shown in Figure 3 and Figure 4 The battery module 4, the upper partition plate 501 and the top surface of the bottom plate 5 are padded with a silica gel plate with good heat conduction performance.

[0035] By adding the silica gel plate, the gap between the battery module 4 and the seat shell can be filled, which not only plays a buffering role but also increases the contact area between the two and improves the heat conduction performance.

[0036] In a specific embodiment of the present application, as shown in Figure 3 and Figure 5As shown, the power battery cooling plate structure of the present application further comprises a filter screen 8, which is installed on the inner side wall of the ventilation opening 201.

[0037] Obviously, the filter screen 8 can also be directly replaced by a mesh plate, that is, a plurality of mesh holes are directly processed in the ventilation opening 201 area of the bottom shell 2 to achieve the effect of ventilation and blocking debris. Similar simple replacement methods are also within the protection scope of the present application.

[0038] Specifically, as shown in Figure 3 and Figure 5 , the bottom shell 2 is integrally provided with a clamping groove at the upper and lower ends of the inner side wall of the ventilation opening 201, and the filter screen 8 is detachably installed in the clamping groove.

[0039] By adding the filter screen 8 to the inner side wall of the ventilation opening 201, the convection wind can be coarsely filtered, and the debris can be prevented from entering and blocking the air duct 6. The filter screen 8 is installed by the clamping groove, which facilitates the disassembly and replacement of the filter screen 8.

[0040] In a specific embodiment of the present application, as shown in Figure 3 and Figure 4 , the cross-sectional shape of the lower heat sink plate 502 is a bent plate, and the distance between the lower heat sink plate 502 and the bottom surface of the bottom shell 2 is between 2-5 mm.

[0041] Specifically, as shown in Figure 3 and Figure 4 , along the longitudinal center plane of the bottom shell 2, the bending directions of the two lower heat sink plates 502 are opposite.

[0042] By setting the lower heat sink plate 502 as a bent plate, on the one hand, the heat dissipation area is increased, and on the other hand, the deformation along the bending direction can occur when the bottom shell 2 is accidentally impacted, which plays a buffering role and reduces the damage of the collision to the battery sealed chamber.

[0043] In a specific embodiment of the present application, as shown in Figure 3 and Figure 4 , a heat dissipation film 11 is also attached to the outer wall of the lower heat sink plate 502, and the heat dissipation film 11 can moisturize and evaporate to cool.

[0044] Specifically, the heat dissipation film 11 uses a cold gel film, and in the invention patent with the publication number CN109943002A, a kind of self-absorbing wet hydrogel, preparation method and heat management method based on it, the cold gel film in the patent can realize the automatic circulation of moisture absorption-heat dissipation, and the heat dissipation effect is excellent.

[0045] Specifically, as shown in Figure 3 and Figure 5As shown, the power battery cooling plate structure of the present invention further includes a spray pipe 9 and a spray cavity 7. The spray cavity 7 is arranged at one end of the bottom shell 2 facing the front of the vehicle, and the spray pipe 9 is arranged on the top of the spray cavity 7.

[0046] Specifically, if Figure 2 and Figure 3 and Figure 5 As shown, the spray pipe 9 is fixedly connected to the top surface of the base plate 5 along the width of the battery pack. Multiple nozzles 901 are evenly spaced and installed on the bottom wall of the spray pipe 9. Nozzles 901 extend into the spray cavity 7. Nozzles 901 are atomizing nozzles. One end of the spray pipe 9 extends beyond the outer wall of the main frame 1 and is provided with a pipe joint 902 that connects to a water source. The water source is a purified water tank with a water pump.

[0047] Specifically, a heating wire and a temperature sensor are installed in the spray pipe 9, and a humidity sensor is buried in the middle of the lower heat sink 502 below the heat dissipation diaphragm 11. The heating wire, temperature sensor and humidity sensor are all electrically connected to the electronic control system of the device.

[0048] When it is detected that the temperature in the spray pipe 9 is below zero, heating is first turned on, and then spraying and humidifying are performed; by setting the humidity sensor, the humidity of the heat dissipation diaphragm 11 can be controlled.

[0049] By arranging a spray cavity 7 and a spray pipe 9 at the end of the bottom shell 2 facing the front of the vehicle, humidification can be sprayed at the air inlet end, and the moisture contacts the heat dissipation diaphragm 11 at the rear, thereby improving the heat dissipation effect; by setting the nozzle 901 as an atomizing nozzle, the moisture can flow backward with the convection wind, thereby improving the overall moisture absorption effect of the heat dissipation diaphragm 11 and avoiding the accumulation of water stains in the bottom shell 2.

[0050] The power battery cooling plate structure of the present invention operates as follows: During vehicle operation, convection air enters through the vent 201 at one end of the spray chamber 7 and rapidly flows through each air duct 6 before being exhausted through the vent 201 at the rear end of the vehicle. Heat from the surface of the lower heat sink 502 within the air duct 6 is removed by the convection air, achieving cooling. Simultaneously, heat generated by the battery modules 4 is continuously transferred to the bottom plate 5 via the silicone plates surrounding and in contact with the bottom surface. The bottom plate 5 then transfers heat downward to the lower heat sink 502. As the surface temperature of the lower heat sink 502 rises, the heat dissipation diaphragm 11 begins to perspire, and the moisture within gradually evaporates, significantly reducing the surface temperature of the lower heat sink 502. When the humidity of the heat dissipation diaphragm 11 drops below a set range, the water pump in the pure water storage tank activates, and all nozzles 901 on the pipe joint 902 spray water mist into the spray chamber 7. This mist, along with the convection air, enters each air duct 6 and is captured by the heat dissipation diaphragms 11 on both sides of the air duct 6, increasing its humidity and causing spraying to cease, thus significantly improving heat dissipation.

[0051] In summary, the power battery cooling plate structure of the present invention divides the original enclosed chamber into an upper equipment sealing chamber and a lower cooling chamber through the bottom plate 5, which facilitates cooling by convection wind passing through the cooling chamber without affecting the sealing performance of the equipment; through the arrangement of the upper partition 501, the four sides and bottom surface of the battery module 4 are in contact with the bottom plate 5, which facilitates the downward conduction of the heat emitted by the battery module 4; through the parallel arrangement of multiple lower heat dissipation plates 502 on the bottom surface of the bottom plate 5, multiple air ducts 6 of uniform size are formed, which facilitate the uniform guidance of convection wind and improve the cooling effect; the upper partition 501 and the lower heat dissipation plates 502 are both integrally arranged on the bottom plate 5, which can not only improve the supporting strength of the bottom plate 5 but also improve the thermal conductivity. The power battery cooling plate structure of the present invention and its working method adopt convection air cooling to achieve cooling of the battery module, which is low in cost and has a relatively good cooling effect. In addition, by adding a silicone plate, the gap between the battery module 4 and the seat shell can be filled, which plays a buffering role on the one hand and increases the contact area between the two on the other hand, thereby improving the thermal conductivity. By adding a filter 8 to the inner wall of the vent 201, coarse filtration of the convective wind can be achieved, preventing debris from entering and clogging the air duct 6. The filter 8 is installed using the slot, which facilitates the removal and replacement of the filter 8. By setting the lower heat sink 502 as a bent plate, on the one hand, the heat dissipation area is increased, and on the other hand, when the bottom shell 2 is accidentally hit, it can deform along the bending direction, playing a buffering role and reducing the damage caused by the collision to the battery sealing chamber. By setting a spray cavity 7 and a spray pipe 9 at the end of the bottom shell 2 facing the front of the vehicle, humidification can be sprayed at the air inlet end, and the moisture contacts the heat dissipation diaphragm 11 at the rear, improving the heat dissipation effect; by setting the nozzle 901 as an atomizing nozzle, the moisture can flow backward with the convective wind, improving the overall moisture absorption effect of the heat dissipation diaphragm 11 and preventing water stains from accumulating in the bottom shell 2.

[0052] The present invention also discloses a working method of a power battery cooling plate structure, which uses the power battery cooling plate structure described in any of the above embodiments to dissipate heat from the battery module, and the partitions around the battery module conduct heat downward and utilize convection wind during vehicle driving for cooling.

[0053] Furthermore, the present invention also provides a spray cavity at the inlet end of the convection air. When it is detected that the humidity of the heat dissipation diaphragm is lower than the set value, the electronic control system of the equipment starts the water pump on the pure water storage tank during the driving of the vehicle, and sprays water mist in the spray cavity to increase the humidity of the air duct, thereby enabling the heat dissipation diaphragm to absorb moisture and improve the heat dissipation.

[0054] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0055] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A power battery cooling plate structure, arranged between a bottom plate (5) and a bottom shell (2) of a battery pack, characterized in that: The bottom plate (5) is connected to the bottom surface of the main shell frame (1) of the protective battery module (4) by bolts, and the top surface of the bottom plate (5) is integrally provided with an upper partition (501), and the upper partition (501) is limited around the battery module (4); the bottom surface of the bottom plate (5) is integrally provided with a lower heat dissipation plate (502), and a plurality of the lower heat dissipation plates (502) are arranged in parallel along the length direction of the bottom plate (5); an air duct (6) is formed between adjacent lower heat dissipation plates (502); the side walls of the bottom shell (2) facing the front and rear of the vehicle are both provided with ventilation openings (201), and the two ends of the air duct (6) face the ventilation openings (201); The cross-sectional shape of the lower heat dissipation plate (502) is a bent plate; A heat dissipation film (11) is also applied to the outer wall of the lower heat dissipation plate (502), and the heat dissipation film (11) is capable of moisturizing and evaporating to cool; It also includes a spray pipe (9) and a spray cavity (7), wherein the spray cavity (7) is arranged at one end of the bottom shell (2) facing the front of the vehicle, and the spray pipe (9) is arranged at the top of the spray cavity (7); The spray pipe (9) is fixedly connected to the top surface of the bottom plate (5) along the width direction of the battery pack; a plurality of nozzles (901) are installed at equal intervals on the bottom wall of the spray pipe (9); the nozzles (901) extend into the spray cavity (7); one end of the spray pipe (9) extends out of the outer wall of the main housing (1) and is provided with a pipe joint (902) connected to a water source.

2. The power battery cooling plate structure according to claim 1, characterized in that: A silica gel plate with good thermal conductivity is provided between the battery module (4), the upper partition (501), and the top surface of the bottom plate (5).

3. The power battery cooling plate structure according to claim 1, characterized in that: It also includes a filter sheet (8), which is installed on the inner wall of the ventilation opening (201).

4. The power battery cooling plate structure according to claim 3, characterized in that: The bottom shell (2) is integrally provided with slots at both upper and lower ends of the inner side wall of the vent (201), and the filter sheet (8) is detachably mounted in the slots.

5. The power battery cooling plate structure according to claim 1, characterized in that: The distance between the lower heat dissipation plate (502) and the bottom surface of the bottom shell (2) is between 2 and 5 mm.

6. The power battery cooling plate structure according to claim 5, characterized in that: Along the longitudinal center plane of the bottom shell (2), the bending directions of the lower heat dissipation plates (502) on both sides are opposite.

7. A method for operating a power battery cooling plate structure, characterized in that: The power battery cooling plate structure described in any one of claims 1 to 6 is used to dissipate heat from the battery module, and the partitions around the battery module conduct heat downward and utilize convection wind during vehicle driving for cooling.

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