Power battery cooling plate structure and working method thereof

Abstract

The invention 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 face of a main shell frame of a protective battery module through bolts, and an upper partition plate is integrally arranged on the top face of the bottom plate; the upper partition plate is limited at the periphery of the battery module; lower heat dissipation plates are integrally arranged on the bottom face of the bottom plate, and the multiple lower heat dissipation plates are arranged in parallel in the length direction of the bottom plate. An air duct is formed between every two adjacent lower heat dissipation plates; ventilation openings are formed in the side walls, facing the vehicle head and the vehicle tail, of the bottom shell, and the two end openings of the air channel face the ventilation openings. Cooling of the battery module is achieved in a convection air cooling mode, the cost is low, and the cooling effect is good.

Description

Technical Field

[0001] The present invention relates to the technical field of power battery cooling, and particularly relates to a power battery cooling plate structure and its working method. Background Art

[0002] During the use of power batteries in new energy electric vehicles, a large amount of heat is generated. When the temperature of the power battery is too high, it will increase the resistance on the relevant conductors, resulting in the loss of electrical energy converted into heat and reducing the battery efficiency. In addition, too high a temperature may also cause thermal runaway of the power battery, thus triggering safety hazards. Therefore, the power battery must be cooled.

[0003] The cooling systems of power batteries are mainly divided into the following categories: 1. Natural cooling, which relies on the rise and fall of the ambient temperature to achieve heat dissipation, and realizes cooling by air flowing over the outer wall of the housing. It is a passive and energy-free solution, suitable for situations with low cooling requirements. 2. Air cooling: Heat is removed by air flow. Active air cooling enhances the cooling effect by a fan agitating air over the cooling air duct, providing more precise control. 3. Liquid cooling: Uses liquid as the heat exchange medium, and its multi-channel heat exchange circuit design endows it with flexibility and high efficiency. The liquid cooling system consists of a radiator, a compressor, an electric water pump, an evaporator, a coolant, a fan, a temperature regulating device, water pipes, and an expansion tank, etc. The coolant is a mixture of water and ethylene glycol, and the heat is carried away through the forced circulation of the coolant. With its excellent cooling performance, flexible adaptability, and reliable stability, liquid cooling technology has become the mainstream choice. 4. Direct cooling: By directly introducing the refrigerant into the battery pack and directly contacting the battery housing for heat exchange. The direct cooling system has the characteristics of efficient heat dissipation, uniform cooling, and fast response.

[0004] For relatively high-class electric vehicles, the third and fourth cooling systems are often adopted, which can achieve better cooling effects. However, such cooling systems will also increase the manufacturing cost and reduce the price competitiveness. For low-end vehicles, if the active air cooling method is adopted, it is still necessary to invest in a fan and a side-mounted air duct assembly, which will not only increase the equipment investment cost but also consume some electrical energy, and it is impossible to achieve the best combination of cost and economy.

[0005] In order to overcome the above problems, a power battery cooling plate structure and its working method are needed. Summary of the Invention

[0006] The object of the present invention is to provide a power battery cooling plate structure and its working method, which use the convective air cooling method to cool the battery module, with low cost and relatively good cooling effect.

[0007] To solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A cooling plate structure for a power battery of the present invention is disposed between the bottom plate and the bottom housing of the battery pack. The bottom plate is connected to the bottom surface of the main housing frame protecting the battery module by bolts. An upper partition is integrally provided on the top surface of the bottom plate, and the upper partition is limited around the battery module. A lower heat dissipation plate is integrally provided on the bottom surface of the bottom plate, and a plurality of the lower heat dissipation plates are arranged in parallel along the length direction of the bottom plate. An air duct is formed between adjacent lower heat dissipation plates. Ventilation openings are provided on the side walls of the bottom housing facing the front and rear of the vehicle, and both ends of the air duct face the ventilation openings.

[0009] Further, a silica gel plate with good thermal conductivity is provided between the battery module, the upper partition, and the top surface of the bottom plate.

[0010] Further, a filter sheet is also included, and the filter sheet is installed on the inner side wall of the ventilation opening.

[0011] Further, clamping grooves are integrally provided at both the upper and lower ends of the inner side wall of the ventilation opening of the bottom housing, and the filter sheet is detachably installed in the clamping grooves.

[0012] Further, the cross-sectional shape 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 housing is between 2 and 5 millimeters.

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

[0014] Further, a heat dissipation film is also attached to the outer wall of the lower heat dissipation plate, and the heat dissipation film can keep moisture and evaporate for refrigeration.

[0015] Further, a spray pipe and a spray cavity are also included. The spray cavity is disposed at one end of the bottom housing facing the front of the vehicle, and the spray pipe is disposed on the top of the spray cavity.

[0016] Further, the spray 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 equally spaced and installed on the bottom wall of the spray pipe, and the nozzles extend into the spray cavity. One end of the spray pipe extends out of the outer wall of the main housing and is provided with a pipe joint communicating with a water source.

[0017] The present invention also discloses a working method for the cooling plate structure of the power battery. The battery module of the cooling plate structure of the power battery described in any one of the above is used for heat dissipation. The heat around the battery module is led downward by the partition, and is cooled by the convection wind during the vehicle driving process.

[0018] Compared with the prior art, the beneficial technical effects of the present invention:

[0019] The cooling plate structure of the power battery of the present invention divides the original sealed chamber into an upper equipment sealed chamber and a lower cooling chamber through a bottom plate. Without affecting the equipment sealing performance, it is convenient to use the convective air passing through the cooling chamber for cooling; through the setting of the upper partition plate, the four sides and the bottom surface of the battery module are in contact with the bottom plate, which is convenient to conduct the heat dissipated by the battery module downward; through a plurality of lower heat dissipation plates arranged in parallel on the bottom surface of the bottom plate, a plurality of air ducts with the same size are formed, which is convenient to evenly guide the convective air and improve the cooling effect; the upper partition plate and the lower heat dissipation plates are integrally arranged on the bottom plate, which can not only improve the support strength of the bottom plate but also improve the heat conduction efficiency. The cooling plate structure of the power battery of the present invention and its working method adopt the convective air cooling method to realize the cooling of the battery module, with low cost and good cooling effect.

[0020] In addition, by adding a silica gel plate, the gap between the battery module and the seat shell can be filled. On the one hand, it plays a buffering role, and on the other hand, it can increase the contact area between the two and improve the heat conduction performance. By adding a filter screen on the inner side wall of the ventilation port, the convective air can be roughly filtered to prevent sundries from entering and blocking the air duct. Using the described card slot to install the filter screen is convenient for the disassembly and replacement of the filter screen. By setting the lower heat dissipation plate as a bent plate, on the one hand, the heat dissipation area is increased, and on the other hand, it can deform along the bending direction when the bottom shell receives an accidental impact, playing a buffering role and reducing the harm of the collision to the battery sealed chamber. By arranging a spray cavity and a spray pipe at one end of the bottom shell facing the vehicle head, humidification can be carried out by spraying at the air inlet end, and the moisture contacts the rear heat dissipation film, improving the heat dissipation effect; by setting the nozzle as an atomizing nozzle, the moisture can flow backward with the convective air, improving the moisture absorption effect of the overall heat dissipation film and preventing water stains from accumulating in the bottom shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below in conjunction with the drawings.

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

[0023] Figure 2 For Figure 1 It is a top view structural schematic diagram of the battery pack after removing the upper shell;

[0024] Figure 3 For Figure 2 It is a sectional structural schematic diagram of part A-A in

[0025] Figure 4 For Figure 2 It is a sectional structural schematic diagram of part B-B in

[0026] Figure 5 For Figure 3Schematic diagram of the partial enlarged structure of part I.

[0027] Description of reference numerals: 1, main housing frame; 101, mounting claw plate; 2, bottom housing; 201, ventilation opening; 3, upper housing; 4, battery module; 5, bottom plate; 501, upper partition plate; 502, lower heat dissipation plate; 6, air duct; 7, spray cavity; 8, filter sheet; 9, spray pipe; 901, nozzle; 902, pipe joint; 10, silica gel pad; 11, heat dissipation film. Specific embodiments

[0028] The core of the present invention is to provide a power battery cooling plate structure and its working method, which realizes the cooling of the battery module by means of convective air cooling, with low cost and relatively good cooling effect.

[0029] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0030] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is 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 orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0031] Referring to the accompanying drawings, Figure 1 is a front view structural schematic diagram of a battery pack with the power battery cooling plate structure of the present invention; Figure 2 is Figure 1 a top view structural schematic diagram of the battery pack after removing the upper housing; Figure 3 is Figure 2 a sectional structural schematic diagram of part A-A in; Figure 4 is Figure 2 a sectional structural schematic diagram of part B-B in; Figure 5 is Figure 3 Schematic diagram of the partial enlarged structure of part I.

[0032] In a specific embodiment, as Figures 1 to 5As shown, the main purpose of the power battery cooling plate structure of the present invention is to improve the existing battery pack lacking a cooling structure, and without significantly increasing the cost, improve its cooling performance, which is applicable to the power batteries of mid - to low - end electric vehicles. The battery pack generally includes a sealed chamber composed of a main housing 1, a bottom housing 2 and an upper housing 3, and a BMS, a battery module 4, a wiring harness, etc. provided in the sealed chamber. The power battery cooling plate structure of the present invention is arranged between the bottom plate 5 of the battery pack and the bottom housing 2. The bottom plate 5 is bolt - connected to the bottom surface of the main housing frame 1 that protects the battery module 4. That is to say, the bottom plate 5 divides the original sealed chamber into an upper equipment sealed chamber and a lower cooling chamber. The bottom plate 5 is made of high - quality stainless - steel sheet. An upper partition 501 is integrally provided on the top surface of the bottom plate 5, and the upper partition 501 is limited around the battery module 4. A lower heat - dissipation plate 502 is integrally provided on the bottom surface of the bottom plate 5, and a plurality of 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. Ventilation openings 201 are provided on the side walls of the bottom housing 2 facing the head and the tail of the vehicle. The two ends of the air duct 6 face the ventilation openings 201, and the ventilation openings 201 are exposed below the vehicle chassis.

[0033] By dividing the original sealed chamber into an upper equipment sealed chamber and a lower cooling chamber through the bottom plate 5, it is convenient to use the convective air passing through the cooling chamber for cooling without affecting the equipment sealing performance; through the setting of the upper partition 501, the periphery and the bottom surface of the battery module 4 are in contact with the bottom plate 5, which is convenient for guiding the heat dissipated by the battery module 4 downward; by arranging a plurality of lower heat - dissipation plates 502 in parallel on the bottom surface of the bottom plate 5 to form a plurality of air ducts 6 with the same size, it is convenient to uniformly guide the convective air and improve the cooling effect; both the upper partition 501 and the lower heat - dissipation plates 502 are integrally provided on the bottom plate 5, which can not only improve the support strength of the bottom plate 5 but also improve the heat - conduction efficiency. The power battery cooling plate structure and its working method of the present invention use the convective air - cooling method to cool the battery module, with low cost and relatively good cooling effect.

[0034] In a specific embodiment of the present invention, as Figure 3 and Figure 4 shown, a silica gel plate with good heat - conduction performance is provided between the battery module 4, the upper partition 501 and the top surface of the bottom plate 5.

[0035] By adding the silica gel plate, the gap between the battery module 4 and the seat shell can be filled. On the one hand, it plays a buffering role, and on the other hand, it can increase the contact area between the two and improve the heat - conduction performance.

[0036] In a specific embodiment of the present invention, as Figure 3 and Figure 5 shown, the power battery cooling plate structure of the present invention further includes a filter screen 8, and the filter screen 8 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 perforated 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 sundries. Similar simple replacement methods all fall within the protection scope of the present invention.

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

[0039] By adding the filter screen 8 on the inner side wall of the ventilation opening 201, rough filtration of the convective air can be achieved, and sundries can be prevented from entering and blocking the air duct 6. Installing the filter screen 8 by using the clamping grooves facilitates the disassembly and replacement of the filter screen 8.

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

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

[0042] By setting the lower heat dissipation plate 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 impacted, deformation occurs along the bending direction, playing a buffering role and reducing the harm of the collision to the battery sealing chamber.

[0043] In a specific embodiment of the present invention, as Figure 3 and Figure 4 shown, a heat dissipation film 11 is also attached to the outer wall of the lower heat dissipation plate 502, and the heat dissipation film 11 can keep moisture and evaporate for refrigeration.

[0044] Specifically, the heat dissipation film 11 adopts a condensation gel film. In a self-absorbing hydrogel, preparation method and heat management method based on the same disclosed in the invention patent with the publication number of CN109943002A, using the condensation gel film in this patent can realize the automatic cycle of moisture absorption - heat dissipation, and the heat dissipation effect is excellent.

[0045] Specifically, as Figure 3 and Figure 5 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 vehicle head, and the spray pipe 9 is arranged at the top of the spray cavity 7.

[0046] Specifically, asFigure 2 and Figure 3 and Figure 5 As shown in Figure 2 and Figure 3 , 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 equidistantly installed on the bottom wall of the spray pipe 9, and the nozzles 901 extend into the spray cavity 7. The nozzles 901 are atomizing nozzles. One end of the spray pipe 9 extends out of the outer wall of the main housing frame 1 and is provided with a pipe joint 902 communicating with the water source. The water source is a pure water storage tank with a water pump.

[0047] Specifically, an electric heating wire and a temperature sensor are installed in the spray pipe 9, and a humidity sensor is buried under the middle position of the middle lower heat dissipation plate 502 under the heat dissipation film 11. The electric heating wire, the temperature sensor, and the humidity sensor are all electrically connected to the electric control system of the device.

[0048] When it is detected that the temperature in the spray pipe 9 is lower than zero degrees, heating is first started, and then spraying and humidification are carried out; through the setting of the humidity sensor, the humidity of the heat dissipation film 11 can be controlled.

[0049] By arranging the spray cavity 7 and the spray pipe 9 at one end of the bottom housing 2 facing the vehicle head, spraying and humidification can be carried out at the air inlet end, the moisture contacts the rear heat dissipation film 11, and the heat dissipation effect is improved; by setting the nozzles 901 as atomizing nozzles, the moisture can flow backward with the convective wind, improving the overall moisture absorption effect of the heat dissipation film 11 and avoiding water stains from accumulating in the bottom housing 2.

[0050] The working principle of the cooling plate structure of the power battery of the present invention: During the driving of the vehicle, the convective wind enters from the ventilation opening 201 at one end of the spray cavity 7 and rapidly flows through each air duct 6, and is discharged from the ventilation opening 201 at the rear end of the vehicle. The heat on the surface of the lower heat dissipation plate 502 in the air duct 6 is carried away by the convective wind, realizing cooling. At the same time, the heat generated by the battery module 4 is continuously transmitted to the bottom plate 5 through the silica gel plates in contact with the surrounding and the bottom surface, and the bottom plate 5 transmits downward to the lower heat dissipation plate 502. When the surface temperature of the lower heat dissipation plate 502 rises, the heat dissipation film 11 starts to sweat, and the internal moisture gradually evaporates, which can significantly reduce the surface temperature of the lower heat dissipation plate 502. When it is detected that the humidity of the heat dissipation film 11 drops below the set range, the water pump of the pure water storage tank starts, and all the nozzles 901 on the pipe joint 902 spray water mist into the spray cavity 7. The water mist enters each air duct 6 along with the convective wind and is captured by the heat dissipation films 11 on both sides of the air duct 6, increasing the humidity, and the spraying stops, thus significantly improving the heat dissipation effect.

[0051] In summary, for the power battery cooling plate structure of the present invention, the original sealed chamber is divided into an upper equipment sealed chamber and a lower cooling chamber by the bottom plate 5. Without affecting the equipment sealing performance, it is convenient to utilize the convective air passing through the cooling chamber for cooling. Through the arrangement of the upper partition plate 501, the periphery and bottom surface of the battery module 4 are in contact with the bottom plate 5, facilitating the downward conduction of the heat dissipated by the battery module 4. By arranging a plurality of lower heat dissipation plates 502 in parallel on the bottom surface of the bottom plate 5 to form a plurality of air ducts 6 with the same size, it is convenient to uniformly guide the convective air and improve the cooling effect. The upper partition plate 501 and the lower heat dissipation plates 502 are integrally arranged on the bottom plate 5, which can not only improve the support strength of the bottom plate 5 but also improve the heat conduction efficiency. The power battery cooling plate structure of the present invention and its working method adopt the convective air cooling method to cool the battery module, with low cost and relatively good cooling effect. In addition, by adding a silica gel plate, the gap between the battery module 4 and the seat shell can be filled. On the one hand, it plays a buffering role, and on the other hand, it can increase the contact area between the two, improving the heat conduction performance. By adding a filter screen 8 on the inner side wall of the ventilation opening 201, the convective air can be roughly filtered to prevent debris from entering and blocking the air duct 6. Using the described card slot to install the filter screen 8 facilitates the disassembly and replacement of the filter screen 8. By setting the lower heat dissipation plate 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 impacted, it can deform along the bending direction, playing a buffering role and reducing the harm of the collision to the battery sealed chamber. By arranging a spray chamber 7 and a spray pipe 9 at one end of the bottom shell 2 facing the vehicle head, humidification can be carried out by spraying at the air inlet end. The moisture contacts the rear heat dissipation film 11 to improve the heat dissipation effect. By setting the nozzle 901 as an atomizing nozzle, the moisture can flow backward with the convective air, improving the moisture absorption effect of the overall heat dissipation film 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 one of the above embodiments to dissipate heat from the battery module. The partition plate around the battery module conducts heat downward and utilizes the convective air during vehicle driving for cooling.

[0053] Furthermore, the present invention also sets a spray chamber at the air inlet end of the convective air. When it is detected that the humidity of the heat dissipation film is less than the set value, during vehicle driving, the equipment electronic control system starts the water pump on the pure water storage tank, and water mist is sprayed in the spray chamber to increase the humidity of the air duct. Then the heat dissipation film can absorb water to improve the heat dissipation situation.

[0054] In the present specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For related parts, reference can be made to the description in the method section.

[0055] The above-described embodiments are only descriptions of the preferred modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined 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 housing frame (1) of the protective battery module (4) by bolts; 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 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); and ventilation openings (201) are provided on the side walls of the bottom shell (2) facing the front and rear of the vehicle, and two ends of the air duct (6) face the ventilation openings (201).

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 plate (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 comprises a filter sheet (8), wherein the filter sheet (8) is installed on the inner wall of the ventilation opening (201).

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

5. The power battery cooling plate structure according to claim 1, characterized in that: The cross-sectional shape of the lower heat dissipation plate (502) is a bent plate, and the distance between the lower heat dissipation plate (502) and the bottom surface of the bottom shell body (2) is between 2 and 5 millimeters.

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. The power battery cooling plate structure according to claim 5 or 6, characterized in that: A heat dissipation film (11) is also attached 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.

8. The power battery cooling plate structure according to claim 7, characterized in that: It also comprises 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).

9. The power battery cooling plate structure according to claim 8, characterized in that: 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.

10. 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 9 is used to dissipate heat from the battery module, and the partitions around the battery module conduct heat downward and use convection wind during vehicle driving to cool the battery module.

Images