Battery thermal management device

Abstract

A battery thermal management device comprises a guide tube, an evaporator and a condenser; the evaporator is arranged below the condenser; the guide tube is connected between the condenser and the evaporator to form a loop; the condenser comprises a box, an air inlet fan, an air outlet fan and a heat dissipation unit; the box is provided with an air inlet and an air outlet, the heat dissipation unit is located between the air inlet and the air outlet; the air inlet fan and the air outlet fan are respectively close to the air inlet and the air outlet. Compared with the prior art, the battery thermal management device of the present invention can improve the efficiency of battery heat dissipation.

Description

Technical Field

[0001] The present invention relates to the technical field of battery thermal management, and in particular to a battery thermal management device. Background Art

[0002] Energy storage technology is one of the key technologies for achieving large-scale application of clean and renewable energy and transformation of energy systems. Renewable energy is often stored in cells, and multiple cells are then integrated into batteries and placed in battery cabinets for storage. Therefore, heat will accumulate in the battery cabinet when the battery is working. In recent years, with the increase in the capacity of energy storage cells, more and more heat will accumulate in the battery cabinet, which will inevitably affect the operating efficiency and service life of the energy storage system. What's more, it may also cause safety accidents such as cell fire and system explosion. Therefore, it is necessary to perform thermal management on the batteries in the battery cabinet. In terms of thermal management, traditional battery cabinets mainly use air convection to take away the heat of the battery. This method either requires a large space to ensure ventilation, or it is difficult to cover the heating position, which is inefficient. In addition, although the prior art also uses immersion thermal management to immerse the entire battery in a solution for cooling, this method can dissipate heat from the various heating parts of the entire battery, but this method requires the battery to be in direct contact with the solution, so there are also certain safety issues. Summary of the invention

[0003] Based on this, an object of the present invention is to provide a battery thermal management device to improve the efficiency of battery heat dissipation.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A battery thermal management device comprises a guide tube, an evaporator and a condenser; the evaporator is arranged below the condenser; the guide tube is connected between the condenser and the evaporator to form a loop; the condenser comprises a housing, an air inlet fan, an air outlet fan and a heat dissipation unit; the housing is provided with an air inlet and an air outlet, and the heat dissipation unit is located between the air inlet and the air outlet; the air inlet fan and the air outlet fan are respectively close to the air inlet and the air outlet.

[0006] Compared with the prior art, the battery thermal management device of the present invention directly dissipates heat from the battery through the phase change of the working fluid in the evaporator and condenser, which can dissipate heat accurately and over a large area, and is efficient, safe and reliable. At the same time, the condenser is cooled by air through the air inlet fan and the air outlet fan, which increases the temperature difference of the working fluid and improves the efficiency of battery heat dissipation.

[0007] In another embodiment, the condenser further includes a spray unit; the spray unit is located on a side close to the air inlet fan, and sprays high-pressure mist toward the heat dissipation unit to further increase the temperature difference of the working fluid and further improve the heat dissipation efficiency of the battery.

[0008] In another embodiment, the heat dissipation unit includes a plurality of fins and a bent tube bent and inserted between the plurality of fins, and the inlet and outlet at both ends of the bent tube are respectively connected to the evaporator through the guide pipe; the spray unit sprays high-pressure aerosol toward the fins, and the mist liquid is transformed into steam on the fins and is carried out of the condenser by the fan. Compared with a single cooling technology, the cooling efficiency is greatly improved and the accumulation of liquid inside the condenser is avoided.

[0009] In another embodiment, the evaporator includes a liquid inlet and an air outlet respectively arranged on two opposite sides thereof; the number of the condensers is more than two, and the outlets of the condensers are connected in parallel to the liquid inlet of the evaporator to improve the heat dissipation effect.

[0010] In another embodiment, the evaporator is a flat plate structure with a plate surface on the outer side, and is provided with a liquid inlet, an air outlet, a accommodating space and a liquid wick, the liquid inlet and the air outlet are respectively located on opposite sides of the accommodating space, and the liquid wick is placed in the accommodating space; the liquid wick has a porous structure, and divides the accommodating space into a compensation chamber and a steam chamber; projected along a direction perpendicular to the outer side of the evaporator, the extension directions of the compensation chamber and the steam chamber are parallel to each other, and are alternately arranged in a direction perpendicular to their extension directions, and the parallel and alternately arranged compensation chambers and steam chambers are conducive to improving heat dissipation efficiency.

[0011] In another embodiment, the liquid absorbent core is provided with a liquid absorbent part, a connecting part, an inlet and an outlet; the inlet is connected with the liquid inlet, and the outlet is connected with the air outlet; the number of the liquid absorbent parts is more than three, and their extension directions are parallel to each other and separated by a distance; the connecting part is connected between two adjacent liquid absorbent parts; the compensation cavity includes two adjacent liquid absorbent parts, the connecting part and the inlet; the steam cavity includes two adjacent liquid absorbent parts, the connecting part and the outlet, so as to form a compensation cavity and a steam cavity parallel to each other.

[0012] In another embodiment, a support column, a liquid diverter plate and a gas converging plate are protrudingly provided in the accommodating space; the support column is inserted in the liquid absorbent core; the liquid diverter plate is located in the compensation cavity; projected in a direction perpendicular to the outer side surface of the evaporator, the liquid diverter plate in the same compensation cavity is located between the two liquid absorbent parts, and the extension direction of the plate surface is parallel to the extension direction of the liquid absorbent part; the gas converging plate is located in the steam cavity; projected in a direction perpendicular to the upper shell plate, the number of gas converging plates in the same steam cavity is more than two, and they are respectively arranged on the two liquid absorbent parts relatively, and the extension direction of the plate surface is parallel to the extension direction of the liquid absorbent part, so that the liquid absorbent core is not easy to shift in the accommodating space, and the liquid working medium is easy to enter the liquid absorbent part, and the gaseous working medium is easy to converge in the steam cavity.

[0013] In another embodiment, a first buffer chamber and a second buffer chamber are further provided in the accommodating space; the first buffer chamber is located between the inlet and the liquid inlet; the second buffer chamber is located between the outlet and the gas outlet to reduce the impact of the working fluid on the evaporator.

[0014] In another embodiment, the evaporator is a tubular structure with a hollow interior, and a liquid inlet and an air outlet are respectively provided at two ends in the axial direction, so as to be suitable for heat dissipation of batteries of different shapes.

[0015] In another embodiment, the number of the evaporators is more than two, and the air outlet of each evaporator is connected in parallel to the inlet of the condenser to dissipate heat for multiple batteries at the same time.

[0016] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the battery thermal management device in the present invention;

[0018] Figure 2 An exploded view of an evaporator in one embodiment of the present invention;

[0019] Figure 3 for Figure 2 A top view of the interior of the evaporator;

[0020] Figure 4 It is a structural schematic diagram of an evaporator in another embodiment of the present invention;

[0021] Figure 5 It is a front view of a battery thermal management device in another embodiment of the present invention;

[0022] Figure 6 A top view of the interior of the battery thermal management device of the present invention;

[0023] Figure 7 It is a schematic diagram of the structure inside the heat dissipation unit of the present invention. DETAILED DESCRIPTION

[0024] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0025] Many techniques and steps are disclosed in describing the present invention, and it should be understood that each of these techniques and steps has its own benefits, and each can also be used in combination with one or more, or in some cases, all other disclosed techniques. Therefore, for the sake of clarity, unnecessary repetition of various possible combinations of various steps will be avoided herein. Of course, it should be clear that these combinations are fully within the scope of the present invention and claims.

[0026] See also Figure 1 The battery thermal management device of the present invention includes a guide tube 10, an evaporator 20 and a condenser 40. The evaporator 20 is horizontally arranged below the condenser 40. The guide tube 10 is connected between the inlet and outlet of the condenser 40 and the evaporator 20 to form a loop, and the working medium flows between the condenser 40 and the evaporator 20 through the guide tube 10. The working medium is any one of deionized water, ethanol, acetone and refrigerant refrigerant. The working medium is in liquid state when it flows out of the condenser 40 to the evaporator 20, and changes into gas state after absorbing the heat energy on the evaporator 20. The gaseous working medium increases the internal pressure of the evaporator 20, and the gaseous working medium flows back into the condenser 40 under the action of pressure. The condenser 40 cools it and turns it back into a liquid working medium, thereby realizing circulation. An energy storage battery (not shown) is connected to the evaporator 20 . When the energy storage battery is charged and discharged at a high rate, a large amount of heat is generated. The heat is transferred to the evaporator 20 through heat conduction to heat the liquid working medium in the evaporator 20 .

[0027] The evaporator 20 has the function of forcing the gas to flow in one direction. Figure 2 and Figure 3In one embodiment, the evaporator 20 is a flat plate structure, including a hollow shell 21, the interior of which forms a storage space (not marked) separated from the outside, and one side of the evaporator 20 is a cover plate 211, the plate surface of which is parallel to the horizontal plane and has a thickness of 0.2mm-5mm. The working medium that can flow in the storage space is phase-changed into steam, and the steam flows into the guide tube 10 under the action of steam blockage, and then flows to the condenser 40. The liquid wick 22 is placed in the storage space to separate the storage space into a compensation chamber 23 and a steam chamber 24. The storage space is provided with a liquid inlet 25 connected to the compensation chamber 23 on one side, and an air outlet 26 connected to the steam chamber 24 on the other side opposite thereto. The outlet of the condenser 40 is connected to the liquid inlet 25 through the guide tube 10, and the air outlet 26 is connected to the inlet of the condenser 40 through the guide tube 10. Assuming that the straight line direction from the liquid inlet 25 to the gas outlet 26 is direction A, projected along the direction perpendicular to the horizontal plane, the extension direction of the compensation chamber 23 and the steam chamber 24 is parallel to the direction A, and they are alternately arranged side by side in the direction perpendicular to the direction A. Preferably, the volume of the steam chamber 24 is larger than the volume of the compensation chamber 23. Further, a first buffer chamber 27 and a second buffer chamber 28 are further provided in the accommodating space. The first buffer chamber 27 is located between the compensation chamber 23 and the liquid inlet 25, and the second buffer chamber 28 is located between the steam chamber 24 and the gas outlet 26.

[0028] The absorbent core 22 has a porous structure, and extends back and forth between the liquid inlet 25 and the air outlet 26 to form a compensation chamber 23 and a steam chamber 24 that are parallel to each other and connected through the porous structure. The porous structure can provide capillary driving force. In this embodiment, the absorbent core 22 is provided with a bottom plate 221, a liquid absorbing portion 222, a connecting portion 223, an inlet 224 and an outlet 225. The bottom plate 221 is located on the inner side plate surface of the shell 21, and more than three liquid absorbing portions 222 are arranged on the side of the bottom plate 221 facing away from the inner side plate surface of the shell 21 and extend along the A direction. The multiple liquid absorbing portions 222 are arranged in parallel in a direction perpendicular to the A direction, and there is a certain gap between two adjacent liquid absorbing portions 222. On the side close to the liquid inlet 25, the connecting portion 223 and the inlet 224 are alternately connected between two adjacent liquid suction portions 222; on the side close to the outlet 225, the connecting portion 223 and the outlet 225 are alternately connected between two adjacent liquid suction portions 222, the inlet 224 is connected to the liquid inlet 25, the outlet 225 is connected to the gas outlet 26, two adjacent liquid suction portions 222 and the connecting portions 223 and the outlet 225 respectively located at both ends of the two liquid suction portions 222 and opposite to each other form the compensation chamber 23, two adjacent liquid suction portions 222 and the connecting portions 223 and the inlet 224 respectively located at both ends of the two liquid suction portions 222 and opposite to each other form the steam chamber 24, and in the direction perpendicular to the A direction, the compensation chamber 23 and the steam chamber 24 are alternately arranged. Further, the first buffer chamber 27 is located between the inlet 224 and the liquid inlet 25, and the second buffer chamber 28 is located between the outlet 225 and the gas outlet 26. The liquid working medium entering the first buffer chamber 27 from the liquid inlet 25 first enters the compensation chamber 23, is sucked into the liquid absorption portion 222 by the porous structure, and is then heated to form steam. The steam enters the steam chamber 24, and then flows toward the second buffer chamber 28 under the action of pressure, and then flows out of the evaporator 20 from the gas outlet 26.

[0029] Furthermore, a plurality of guide plates 29, support columns 30, liquid diverter plates 31 and gas convergence plates 32 are protrudingly provided in the accommodating space. At least one of the guide plates 29, the support columns 30, the liquid diverter plates 31 and the gas convergence plates 32 passes through the liquid wick 22 in a direction perpendicular to the horizontal plane to limit the position thereof. A plurality of support columns 30 are protrudingly provided in at least one of the compensation chamber 23, the steam chamber 24, the first buffer chamber 36 and the second buffer chamber 37 at even intervals to support the shell 21. The liquid diverter plate 31 is located in the compensation chamber 23. Projected in a direction perpendicular to the horizontal plane, in the same compensation chamber 23, the number of the liquid diverter plates 31 is more than two, and they are arranged at equal intervals along the A direction to evenly distribute the liquid working medium in the compensation chamber 23. The plate surfaces of each liquid diverter plate 31 face the two liquid suction parts 222 respectively, and the plate surfaces extend along the A direction, and have a certain gap with the two liquid suction parts 222. The liquid working medium entering the compensation chamber 23 is diverted by the liquid diverter plate 31 and pressed into the liquid suction parts 222 on both sides. The gas convergence plate 32 is located in the steam chamber 24. In the same steam chamber 24, there are more than two gas convergence plates 32, and each gas convergence plate 32 is respectively opposite to the two liquid suction parts 322, and the extension direction of its plate surface is parallel to the A direction. The gaseous working medium coming out of the liquid suction part 222 is converged by the gas convergence plate 32 to the middle of the steam chamber 24, reducing the reflux of steam to the liquid suction part 222. The guide plates 29 are respectively arranged in the first buffer chamber 36 and the second buffer chamber 37. In the first buffer chamber 36, a guide plate 29 is provided near each inlet 324, one end of the guide plate 29 is close to the inlet 324, and the other end extends toward the liquid inlet 38. When projected in a direction perpendicular to the horizontal plane, the extension direction of the guide plate 29 is not parallel to the A direction, and the liquid medium entering from the liquid inlet 38 flows along the plate surface of the guide plate 29 toward each inlet 224. In the second buffer chamber 37, when projected in a direction perpendicular to the horizontal plane, a guide plate 29 is provided near each outlet 225, one end of the guide plate 29 is close to the outlet 225, and the other end extends toward the gas outlet 26, so as to guide the steam in the steam chamber 24 from the outlet 225 to the gas outlet 26.

[0030] Furthermore, the number of the evaporators 20 is more than two, the liquid inlet 25 of one evaporator 20 is connected to the liquid inlet 25 of another evaporator 20, the guide pipe 10 connected to the outlet of the condenser 40 is connected to the air outlet 26 of the two evaporators 20 at the same time through a T-joint, and the air outlet 26 of each evaporator 20 is connected in parallel to the inlet of the condenser 40.

[0031] See also Figure 5In another embodiment, the evaporator 20 is a tubular structure with a diameter of 4mm-20mm, and is hollow inside and provided with a liquid wick. Specifically, a heat pipe structure such as a groove type, a sintered type or a composite type in the prior art can be adopted. In the axial direction of the evaporator 20, the liquid inlet 25 and the gas outlet 26 are arranged on both sides thereof to adapt to different heat source positions, intensities or heat source carrier shapes. Furthermore, there are more than two evaporators 20, and the liquid inlet 25 and the gas outlet 26 of each evaporator 20 are respectively arranged in parallel.

[0032] Please refer to Figure 5 and Figure 6 The condenser 40 includes a housing 41, an air inlet fan 42, an air outlet fan 43, a spray unit 44 and a heat dissipation unit 45. An air inlet 411 and an air outlet 412 are provided on opposite sides of the housing 41, and the heat dissipation unit 45 is located between the air inlet 411 and the air outlet 412. The air inlet fan 42 and the air outlet fan 43 are respectively close to the air inlet 411 and the air outlet 412 to promote external airflow to enter the housing 41 from the air inlet 411 and flow out of the housing 41 from the air outlet 412. The spray unit 44 and the heat dissipation unit 45 are located in the housing 41, and the spray unit 44 is located on a side close to the air inlet 411. Preferably, the spray unit 44 is located between the heat dissipation unit 45 and the air inlet fan 42. Furthermore, the number of the condensers 40 is more than two, and the outlets of the condensers 40 are connected in parallel to the liquid inlet 25 of the evaporator 20 .

[0033] The spray unit 44 can be a spray device with a spray pressure adjustment function in the prior art, which can adjust the spray volume, atomization degree and range. In this embodiment, the spray unit 44 includes a liquid storage 441 and a nozzle 442. The liquid storage 441 contains a coolant including deionized water, nanofluid, and ethylene glycol aqueous solution. The nozzle 442 is connected to the liquid storage 441 and sprays the atomized coolant toward the heat dissipation unit 45.

[0034] See also Figure 7 The heat dissipation unit 45 includes a plurality of fins 451 and a bent tube 452 bent and inserted between the plurality of fins 451. The two ends of the bent tube 452 are respectively connected to the liquid inlet 25 and the air outlet 26 of the evaporator 20 through the guide tube 10. Under the action of the air inlet fan 42 and the air outlet fan 43, the high-pressure mist sprayed by the spray unit 44 acts on the fins 451 to form steam, and then the steam flows out of the box 41 from the air outlet 412, which greatly improves the cooling efficiency of the energy storage system and prevents liquid from gathering in the box 41.

[0035] Based on the above structure, the working process of the battery thermal management device of the present invention is described through this embodiment.

[0036] In one embodiment, the air inlet fan 42 and the air outlet fan 43 are turned on, the spray unit 44 does not spray, and the fins 451 are in a natural convection heat dissipation state. The condensation rate of the working fluid in the bent tube 452 is extremely low. Therefore, it is suitable for situations where the battery charge is small and the heat source intensity is small.

[0037] In another embodiment, the air inlet fan 42 and the air outlet fan 43 are turned on to perform forced convection heat exchange on the fins 451, and the condensation rate of the working medium in the bent tube 452 is low. Therefore, it is suitable for situations where the battery charge is large and the heat source intensity is large.

[0038] In another embodiment, the air inlet fan 42 and the air outlet fan 43 are turned on, and the spray unit 44 is turned on to perform phase change heat treatment on the fins 451. The spray sprayed by the spray unit 44 is phase-changed into steam on the fins 451. The air inlet fan 42 and the air outlet fan 43 bring the steam out of the box 41. The condensation rate of the working fluid in the bent tube 452 is relatively high. Therefore, it is suitable for situations where the battery charge is large and the heat source intensity is large.

[0039] Compared with the prior art, the battery thermal management system of the present invention has the following advantages:

[0040] 1) Spray-type liquid cooling combined with air cooling technology is used to dissipate the heat derived from the evaporator. The pressure of the spray unit is controlled to spray out a nearly mist-like liquid. The mist-like liquid changes into steam on the fins and is carried out of the condenser by the fan. Compared with a single cooling technology, the cooling efficiency is greatly improved and the liquid is prevented from gathering inside the condenser.

[0041] 2) Phase change heat transfer devices are used as evaporators, which can accurately and widely cover the location of the battery heat source, achieving efficient heat extraction from the battery while avoiding direct contact between the liquid and the battery.

[0042] 3) The structural design is compact, simple and has low maintenance cost. The number and shape of the evaporators can be flexibly designed according to the number and location of the heat sources to achieve efficient cooling.

[0043] 4) There are multiple battery cooling modes, and different cooling methods can be selected according to the situation, which is energy-saving and environmentally friendly.

[0044] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A battery thermal management device, characterized in that: The invention comprises a guide tube, an evaporator and a condenser; the evaporator is arranged below the condenser; the guide tube is connected between the condenser and the evaporator to form a loop; the condenser comprises a box, an air inlet fan, an air outlet fan and a heat dissipation unit; the box is provided with an air inlet and an air outlet, the heat dissipation unit is located between the air inlet and the air outlet; the air inlet fan and the air outlet fan are respectively close to the air inlet and the air outlet; The evaporator comprises a hollow shell and a liquid wick; a liquid inlet and an air outlet are respectively arranged on opposite sides of the shell; the liquid wick has a porous structure and is placed in the shell, dividing the interior of the shell into a compensation chamber connected to the liquid inlet and a steam chamber connected to the air outlet; the outlet of the condenser is connected to the liquid inlet, and the inlet of the condenser is connected to the air outlet; The extension directions of the compensation chamber and the steam chamber are parallel to each other and point from the liquid inlet to the gas outlet, and the compensation chamber and the steam chamber are alternately arranged in a direction perpendicular to their extension directions; A liquid diverter plate and a gas converging plate are protrudingly provided in the shell; the liquid diverter plate is located in the compensation chamber, with its plate surface facing the steam chamber and having a gap with the liquid absorbent core; the gas converging plate is located in the steam chamber, and there are more than two gas converging plates in the same steam chamber, and each gas converging plate is relatively arranged on the liquid absorbent core on both sides of the steam chamber, with its plate surface facing the compensation chamber.

2. The battery thermal management device according to claim 1, characterized in that: The condenser further comprises a spray unit; the spray unit is located at a side close to the air inlet fan and sprays high-pressure mist toward the heat dissipation unit.

3. The battery thermal management device according to claim 2, characterized in that: The heat dissipation unit includes a plurality of fins and a bent tube bent and inserted between the plurality of fins, and inlets and outlets at both ends of the bent tube are respectively connected to the evaporator through the guide tube; the spray unit sprays high-pressure mist toward the fins.

4. The battery thermal management device according to claim 3, characterized in that: The evaporator comprises a liquid inlet and a gas outlet respectively arranged on two opposite sides thereof; the number of the condensers is more than two, and the outlets of the condensers are connected in parallel to the liquid inlet of the evaporator.

5. The battery thermal management device according to claim 1, characterized in that: The evaporator is a flat plate structure with a plate surface on the outer side, and a containing space is formed in the shell. The liquid inlet and the gas outlet are respectively located on opposite sides of the containing space. The liquid absorption core is placed in the containing space, and the liquid diverter plate and the gas converging plate are protruded in the containing space.

6. The battery thermal management device according to claim 5, characterized in that: The liquid absorbent core is provided with a liquid absorbent part, a connecting part, an inlet and an outlet; the inlet is connected with the liquid inlet, and the outlet is connected with the air outlet; the number of the liquid absorbent parts is more than three, and their extension directions are parallel to each other and separated by a distance; the connecting part is connected between two adjacent liquid absorbent parts; the compensation chamber includes two adjacent liquid absorbent parts, the connecting part and the inlet; the steam chamber includes two adjacent liquid absorbent parts, the connecting part and the outlet.

7. The battery thermal management device according to claim 6, characterized in that: A support column is also protruding from the accommodating space; the support column is inserted into the liquid absorbent core.

8. The battery thermal management device according to claim 7, characterized in that: A first buffer cavity and a second buffer cavity are further provided in the accommodating space; the first buffer cavity is located between the inlet and the liquid inlet; and the second buffer cavity is located between the outlet and the air outlet.

9. The battery thermal management device according to claim 5, characterized in that: The number of the evaporators is more than two, and the gas outlet of each evaporator is connected in parallel to the inlet of the condenser.

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