阅读说明：本技术 动力电池热管理系统 (Power battery thermal management system ) 是由 杨辉著 朱永刚 马彬健 于 2021-08-13 设计创作，主要内容包括：本发明公开了一种动力电池热管理系统。本发明的动力电池热管理系统实现了冷媒的直接冷却和预热,降低了动力电池热管理系统的复杂性、重量和功耗,实现了动力电池良好的均温性和快速响应特征,维持动力电池高效、安全地运行。(The invention discloses a power battery thermal management system. The power battery heat management system disclosed by the invention realizes direct cooling and preheating of the refrigerant, reduces the complexity, weight and power consumption of the power battery heat management system, realizes good temperature uniformity and quick response characteristics of the power battery, and maintains the high-efficiency and safe operation of the power battery.)

1. Power battery thermal management system, its characterized in that includes:

a power battery pack;

the first flat heat pipe is arranged on the upper surface of the power battery pack;

the second flat plate heat pipe is arranged on the lower surface of the power battery pack, and working media are arranged in the first flat plate heat pipe and the second flat plate heat pipe;

the evaporative condenser is at least provided with one, the evaporative condenser is arranged between the first flat heat pipe and the second flat heat pipe, a first inlet and a first outlet are formed in the upper half part of the first end of the evaporative condenser, a second inlet and a second outlet are formed in the lower half part of the second end of the evaporative condenser, and the evaporative condenser can exchange heat with the first flat heat pipe and the second flat heat pipe.

2. The power battery thermal management system of claim 1, wherein wicks are disposed within the first planar heat pipe and within the second planar heat pipe, and wherein support posts and securing structures are disposed within the first planar heat pipe and within the second planar heat pipe, the support posts reinforcing the structural strength of the first planar heat pipe and the second planar heat pipe, and the securing structures securing the wicks.

3. The power cell thermal management system of claim 2, wherein the wick has a thickness of 0.01 to 0.25 times a tube diameter of the first flat plate heat pipe.

4. The power battery thermal management system of claim 1, wherein the evaporative condenser comprises an upper cover plate and a lower cover plate, the first access opening is disposed at an end of the upper cover plate, and the second access opening is disposed at an end of the lower cover plate.

5. The power battery thermal management system of claim 4, wherein an inner wall surface of the upper cover plate is provided with a first pin rib array, and a hydrophobic layer is provided on the first pin rib array.

6. The power battery thermal management system of claim 4 or 5, wherein the inner wall surface of the lower cover plate is provided with a second pin rib array, and a hydrophilic layer is arranged on the second pin rib array.

7. The power battery heat management system according to claim 4, wherein a first pin rib array is arranged on the inner wall surface of the upper cover plate, a second pin rib array is arranged on the inner wall surface of the lower cover plate, a plurality of stages of branch passages are included in the first pin rib array and the second pin rib array, and the ratio of the length of each stage of branch passage to the equivalent diameter is 5-10.

8. The power battery thermal management system of claim 7, wherein the ratio of the equivalent diameter of the branch passage of the next stage to the equivalent diameter reached by the branch passage of the previous stage is 0.3-0.6.

9. The power battery thermal management system of claim 1, wherein the evaporative condenser is disposed within or on one side of the power battery pack, and the evaporative condenser is disposed in parallel with the power batteries within the power battery pack.

10. The power battery thermal management system of claim 1, wherein the evaporative condenser is disposed on one side of the power battery pack, and the evaporative condenser is disposed perpendicular to the power batteries in the power battery pack.

Technical Field

The invention relates to the technical field of battery management, in particular to a power battery thermal management system.

Background

In the related art, the electric automobile as a strategic emerging industry rises rapidly along with the wave of low-carbon economy, becomes a strategic choice for the transformation of energy conservation and green development of the global automobile industry, and becomes an important engine for promoting the continuous growth of the world economy. The power battery is the most central component of the electric automobile, and the capacity, the service life, the charging and discharging time and the safety of the power battery are seriously limited by the working temperature of the battery. When the power battery works under the high-temperature or low-temperature working condition, the performance of the battery is rapidly reduced, the service life is accelerated to be attenuated, and even safety accidents such as combustion, fire, explosion and the like are caused, so that the establishment of the efficient power battery thermal management system is of great significance for solving the heat dissipation problem of the power battery in the super fast charge and high heat flux density and the rapid preheating problem in the low-temperature environment.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a power battery thermal management system which can effectively solve the problems of heat dissipation and preheating of a power battery, so that the power battery can operate efficiently and safely.

The power battery thermal management system comprises a power battery pack, a first flat heat pipe, a second flat heat pipe and an evaporative condenser, wherein the first flat heat pipe is arranged on the power battery pack; the first flat heat pipe is arranged on the upper surface of the power battery pack; the second flat plate heat pipe is arranged on the lower surface of the power battery pack, and working media are arranged in the first flat plate heat pipe and the second flat plate heat pipe; at least one evaporative condenser is arranged, the evaporative condenser is arranged between the first flat heat pipe and the second flat heat pipe, a first inlet and a first outlet are formed in the upper half portion of the first end of the evaporative condenser, a second inlet and a second outlet are formed in the lower half portion of the second end of the evaporative condenser, and the evaporative condenser can exchange heat with the first flat heat pipe and the second flat heat pipe.

The power battery thermal management system provided by the embodiment of the invention at least has the following beneficial effects: through the first flat heat pipe and the second flat heat pipe which are provided with the working medium, the heat of the evaporative condenser can be effectively transmitted to the power battery pack, the first inlet and the second outlet with the height difference enable the evaporative condenser to effectively transmit the heat to the first flat heat pipe and the second flat heat pipe, so that the heat is transmitted to the power battery pack, the power battery pack is quickly and effectively cooled and preheated, the power battery is enabled to keep good temperature uniformity and quick response characteristics, and the power battery is enabled to operate efficiently and safely.

According to some embodiments of the present invention, liquid absorbing cores are disposed in the first flat heat pipe and the second flat heat pipe, and a supporting column and a fixing structure are disposed in the first flat heat pipe and the second flat heat pipe, wherein the supporting column is used for reinforcing structural strength of the first flat heat pipe and the second flat heat pipe, and the fixing structure is used for fixing the liquid absorbing cores.

According to some embodiments of the invention, the thickness of the wick is 0.01 to 0.25 times the tube diameter of the first flat heat pipe.

According to some embodiments of the invention, the evaporative condenser comprises an upper cover plate and a lower cover plate, the first access opening is provided at an end of the upper cover plate, and the second access opening is provided at an end of the lower cover plate.

According to some embodiments of the present invention, the inner wall surface of the upper cover plate is provided with a first pin rib array, and the first pin rib array is provided with a hydrophobic layer thereon, so as to realize enhanced condensation heat transfer.

According to some embodiments of the invention, the inner wall surface of the lower cover plate is provided with a second pin fin array, and the second pin fin array is provided with a hydrophilic layer thereon, so as to realize enhanced evaporation heat transfer.

According to some embodiments of the present invention, a first pin fin array is disposed on an inner wall surface of the upper cover plate, a second pin fin array is disposed on an inner wall surface of the lower cover plate, each of the first pin fin array and the second pin fin array includes a plurality of stages of branch passages therein, and a ratio of a length of each stage of the branch passages to an equivalent diameter is 5 to 10.

According to some embodiments of the invention, a ratio of an equivalent diameter of the branch passage of the next stage to an equivalent diameter reached by the branch passage of the previous stage is 0.3 to 0.6.

According to some embodiments of the invention, the evaporative condenser is arranged in the power battery pack or on one side of the power battery pack, and the evaporative condenser is arranged in parallel with the power batteries in the power battery pack according to different arrangement directions of the power batteries.

According to some embodiments of the invention, the evaporative condenser is disposed on a side of the power battery pack, and the evaporative condenser is disposed perpendicular to the power cells within the power battery pack.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The invention is further described with reference to the following figures and examples, in which:

FIG. 1 is a schematic diagram of a power battery thermal management system according to an embodiment of the invention;

FIG. 2 is a front view of a power cell thermal management system according to an embodiment of the present invention;

FIG. 3 is a rear view of a power cell thermal management system according to an embodiment of the present invention;

FIG. 4 is an exploded view of a first flat heat pipe (a second flat heat pipe) according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a power cell thermal management system according to another embodiment of the invention;

fig. 6 is a schematic inside view of an upper cover plate of an evaporative condenser according to an embodiment of the present invention.

Reference numerals:

the heat exchanger comprises a first flat heat pipe 110, a second flat heat pipe 120, a liquid absorption core 111, a support column 112, a fixing structure 113, a power battery pack 130, an evaporative condenser 140, a first inlet/outlet 141, a second inlet/outlet 142 and a first pin rib array 143; a first stage bypass channel 210, a second stage bypass channel 220, and a third stage bypass channel 230.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the meaning of a plurality is one or more, the meaning of a plurality is two or more, and the above, below, exceeding, etc. are understood as excluding the present numbers, and the above, below, within, etc. are understood as including the present numbers. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

In the description of the present invention, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

In the related technology, because the heat conductivity coefficient and the specific heat capacity of air are low, the air cooling technology is difficult to solve the heat dissipation problem of high-rate charge and discharge of the power battery, and the defects of large air temperature rise, poor battery temperature uniformity and the like exist; the liquid cooling technology is a mainstream heat management scheme of a plurality of commercial electric vehicle power batteries at present, a secondary cooling device and a pumping power conveying system are required to be added for liquid cooling, and the problems of complex system, high power consumption, heavy weight and the like exist, so the direct cooling technology of the power batteries is started to be applied to the electric vehicles, but the power batteries are cooled mainly based on the original water cooling plate or micro-channel at present, and the power batteries are preheated by adopting methods such as an electric heating film and the like, and meanwhile, the water cooling plate or micro-channel evaporator with a linear structure cannot avoid the problems of unstable flow, large flow resistance, low heat transfer performance and the like existing at the downstream of a channel.

Therefore, the invention provides a power battery heat management system, which realizes direct cooling and preheating of a refrigerant, reduces the complexity, weight and power consumption of the power battery heat management system, realizes good temperature uniformity and quick response characteristics of a power battery, and maintains the high-efficiency and safe operation of the power battery.

The invention will be further elucidated with reference to the drawing.

Referring to fig. 1, 2 and 3, in some embodiments of the present invention, a first flat heat pipe 110 and a second flat heat pipe 120 are disposed in parallel, the first flat heat pipe 110 is disposed on an upper surface of a power battery pack 130, and the second flat heat pipe 120 is disposed on a lower surface of the power battery pack 130, i.e., the first flat heat pipe 110 and the second flat heat pipe 120 sandwich the power battery pack 130, it should be understood that the power battery pack 130 includes a plurality of power batteries, i.e., a plurality of power batteries are arranged in parallel to form the power battery pack 130. Working media for heat exchange are arranged in the first flat heat pipe 110 and the second flat heat pipe 120, and it should be noted that the working media include deionized water, acetone, methanol, heptane, ethanol, methanol, ammonia, and carbon dioxide.

The evaporative condenser 140 is disposed between the first flat heat pipe 110 and the second flat heat pipe 120, and at least one evaporative condenser 140 is disposed, and the evaporative condenser 140 exchanges heat with the first flat heat pipe 110 and the second flat heat pipe 120. When the evaporative condenser 140 is provided in plural, the plural evaporative condensers 140 may be arranged in a dispersed manner, such as being provided between the plural power battery packs 130, that is, one evaporative condenser 140 is provided between every two power battery packs 130.

A first inlet and outlet 141 and a second inlet and outlet 142 are respectively arranged at two ends of the evaporative condenser 140, for example, the first end of the evaporative condenser 140 is provided with the first inlet and outlet 141, and the first inlet and outlet 141 is located at the upper half of the first end of the evaporative condenser 140; the second end of the evaporative condenser 140 is provided with a second inlet/outlet 142, and the second inlet/outlet 142 is located at the lower half part of the second end of the evaporative condenser 140, i.e. there is a height difference between the first inlet/outlet 141 and the second inlet/outlet 142, so that the condensed liquid or the evaporated gas can flow out conveniently, and the heat exchange efficiency is improved. It should be noted that the first end and the second end of the evaporative condenser 140 are opposite ends. It can be understood that when the power battery pack 130 needs to dissipate heat at a high temperature, the liquid refrigerant flows into the evaporative condenser 140 through the second inlet/outlet 142, flows out from the first inlet/outlet 141 after undergoing an evaporative phase change, and when the power battery pack 130 needs to be preheated at a low temperature, the vapor refrigerant flows into the evaporative condenser 140 through the first inlet/outlet 141, and flows out from the second inlet/outlet 142 after undergoing a condensed phase change.

The first inlet/outlet 141 and the second inlet/outlet 142 have a height difference, and the first inlet/outlet 141 is higher than the second inlet/outlet 142, so that the liquid refrigerant flows in from the second inlet/outlet 142 with a low position, and due to evaporation and heat absorption, the evaporated refrigerant takes away heat, and the refrigerant after phase change by evaporation has a low density, rises and flows out from the first inlet/outlet 141 with a high position; when the vapor refrigerant flows in from the first inlet/outlet 141 located at a high position and the liquefied refrigerant releases heat due to liquefaction and heat release, the liquefied and phase-changed refrigerant flows out from the second inlet/outlet 142 located at a low position by gravity. By providing the first inlet/outlet 141 and the second inlet/outlet 142 having a height difference, the refrigerant may be guided by gravity without being excessively introduced, which is helpful to improve the fluidity of the refrigerant in the evaporative condenser 140 and enhance the performance of the evaporative condenser 140.

The heat of the evaporative condenser 140 can be effectively transferred to the power battery pack 130 through the first flat heat pipe 110 and the second flat heat pipe 120 which are provided with the working medium, and the evaporative condenser 140 can effectively transfer the heat to the first flat heat pipe 110 and the second flat heat pipe 120 through the first inlet and outlet 141 and the second inlet and outlet 142 which have the height difference, so that the heat is transferred to the power battery pack 130, the heat is quickly and effectively dissipated and preheated for the power battery pack 130, the power battery keeps good temperature uniformity and quick response characteristics, and the high-efficiency and safe operation of the power battery is maintained.

Referring to fig. 4, in some embodiments of the present invention, a wick 111 is disposed in each of the first and second flat heat pipes 110 and 120, and a support column 112 is further disposed, and the support column 112 penetrates the wick 111 and supports the first and second flat heat pipes therein, so as to enhance rigidity to prevent the first and second flat heat pipes from collapsing. And the fixing structures 113 are further respectively arranged in the first flat heat pipe 110 and the second flat heat pipe 120, and the fixing structures 113 are used for supporting the liquid absorption cores 111, so that gaps exist between the liquid absorption cores 111 and the inner walls of the first flat heat pipe 110 and the second flat heat pipe 120, and heat transfer is faster. It is understood that the fixing structure 113 may be a fixing post, such as a plurality of fixing posts disposed on the inner walls of the first flat heat pipe 110 and the second flat heat pipe 120 by injection molding; the fixing structure 113 may also be a micro-nano structure, for example, the micro-nano structure is processed on the inner walls of the first flat heat pipe 110 and the second flat heat pipe 120, that is, the micro-nano structure is formed by adopting a nano-scale process, and the micro-nano structure is coupled with the liquid absorption core 111 in a double-layer coupling manner, so that the heat transfer performance of the first flat heat pipe 110 and the second flat heat pipe 120 is enhanced, and the micro-nano structure has a small scale, so that the heat distribution is more uniform. It should be noted that the liquid absorption core 111 is fully impregnated with working media, and similarly, the working media can also flow between the fixed column or the micro-nano structure to play a role in drainage.

In some embodiments of the present invention, the thickness of the wick 111 is 0.01 to 0.25 times the pipe diameter of the first flat heat pipe 110, and it is contemplated that the thickness of the wick 111 may also be 0.01 to 0.25 times the pipe diameter of the second flat heat pipe 120. When the thickness of the liquid absorbing core 111 is 0.01 times of the pipe diameter of the first flat heat pipe 110, the liquid absorbing core 111 can absorb enough working media, so that heat is transferred quickly, and heat dissipation and preheating of the power battery pack 130 are facilitated; when the thickness of the liquid absorbing core 111 is 0.25 times of the pipe diameter of the first flat heat pipe 110, the thickness proportion of the liquid absorbing core 111 in the first flat heat pipe 110 is large, so that the liquid absorbing core 111 can absorb enough working media, heat can be transferred more quickly, the heat dissipation and the preheating of the power battery pack 130 are accelerated, and the heat dissipation duration and the preheating duration of the power battery pack 130 are effectively shortened.

In some embodiments of the present invention, the evaporative condenser 140 includes an upper cover plate and a lower cover plate, the first access opening 141 is provided at an end of the upper cover plate, and the second access opening 142 is provided at an end of the lower cover plate, it being contemplated that the first access opening 141 is provided at a first end of the upper cover plate, and the second access opening 142 is provided at a second end of the lower cover plate, the second end of the lower cover plate being oriented in the same direction as the first end of the upper cover plate.

Referring to fig. 6, in some embodiments of the present invention, the inner wall surface of the upper cover plate is provided with a first pin rib array 143, and a hydrophobic layer is provided on the first pin rib array 143. The first needle rib array 143 is arranged in an array by a plurality of needle ribs such that fluid can flow in the first needle rib array 143, and channels for fluid flow can be formed between the needle ribs to uniformly distribute the fluid. The hydrophobic layer can be a coating formed by hydrophobic paint, such as fluorocarbon paint, polyurethane paint and the like; the hydrophobic layer can also be a super-hydrophobic coating film made of fluorine-containing polymers such as fluorinated polyethylene, fluorocarbon wax and the like. Through the setting of hydrophobic layer, can promote the efficiency of condensation to strengthen the effect of evaporative condenser 140 condensation heat transfer.

In some embodiments of the present invention, the inner wall surface of the lower cover plate is provided with a second pin fin array, and a hydrophilic layer is provided on the second pin fin array. Similarly, the second pin fin array is also arranged in an array by a plurality of pin fins, so that the fluid can flow in the second pin fin array, and channels for the fluid to flow can be formed among the pin fins, and the fluid is uniformly distributed. The hydrophilic layer may be hydrophilic cotton, hydrophilic fiber or hydrophilic leather. Through the arrangement of the hydrophilic layer, the evaporation efficiency can be improved, so that the evaporation heat exchange effect of the evaporative condenser 140 is enhanced.

In some embodiments of the present invention, the inner wall surface of the upper cover plate of the evaporative condenser is provided with a first pin fin array 143, the inner wall surface of the lower cover plate is provided with a second pin fin array, and a multi-stage branch passage is included in each of the first pin fin array 143 and the second pin fin array, it being understood that the branch passage is a passage through which a fluid flows. The first needle rib array 143 and the second needle rib array each include a plurality of sets of needle ribs, and the plurality of sets of needle ribs are arranged in an array, so that a branch channel is formed between each set of needle ribs, so that the fluid can be uniformly distributed and flow. The ratio of the length of each stage of the branch channel to the equivalent diameter is 5-10, and it is thought that the equivalent diameter represents the maximum flow width of the branch channel for accommodating fluid flow. Through the branch passages, the fluid can be uniformly distributed in the evaporative condenser, and the heat exchange efficiency is improved, so that the evaporative condenser can better exchange heat with the first flat heat pipe and the second flat heat pipe.

Referring to fig. 6, which shows a schematic layout of the first pin fin array 143 on the inner wall surface of the upper cover plate, the first pin fin array 143 includes three stage branch passages, which are divided into a first stage branch passage 210, a second stage branch passage 220, and a third stage branch passage 230 in order from large to small according to the equivalent diameter, the first stage branch passage 210 and the third stage branch passage 230 are arranged in parallel, and the second stage branch passage 220 is perpendicular to the first stage branch passage 210 and the third stage branch passage 230. Wherein the first stage branch passage 210 has a length of L1 and an equivalent diameter of D1; the second stage branch passage 220 has a length of L2 and an equivalent diameter of D2; the length of the third-stage branch channel 230 is L3, the equivalent diameter is D3, the ratio of the length of each stage of branch channel to the equivalent diameter is 5-10, that is, the ratio of L1 to D1 is 5-10, the ratio of L2 to D2 is 5-10, and the ratio of L3 to D3 is 5-10, it should be understood that the ratio of the length of the first-stage branch channel 210 to the equivalent diameter, the ratio of the length of the second-stage branch channel 220 to the equivalent diameter, and the ratio of the length of the third-stage branch channel 230 to the equivalent diameter may be equal, any two of them may be equal, or none of them may be equal, and the above ranges may be satisfied. It should be appreciated that the number of the branch channels can be increased or decreased according to the design requirement, and the length and the equivalent diameter of the branch channels both conform to the fractal principle.

When the ratio of the length of the branch channel to the equivalent diameter is 5, the length of the branch channel is 5 times of the equivalent diameter, the branch channel can be adapted to a conventional power battery, and the equivalent diameter is larger, so that more refrigerant fluid can flow in unit time, and the heat dissipation and preheating processes of the power battery pack are accelerated.

When the ratio of the length of the branch channel to the equivalent diameter is 10, the length of the branch channel is 10 times of the equivalent diameter, the branch channel is long and narrow, is suitable for a power battery with a longer length, and can delay the time of refrigerant fluid in the evaporative condenser, so that the heat exchange time is prolonged, and the heat exchange is carried out more fully.

In some embodiments of the present invention, the ratio of the equivalent diameter of the next-stage bypass channel to the equivalent diameter of the previous-stage bypass channel is 0.3 to 0.6, and it can be understood that, referring to fig. 6, the ratio of the equivalent diameter D3 of the third-stage bypass channel 230 to the equivalent diameter D2 of the second-stage bypass channel 220 is 0.3 to 0.6, and the ratio of the equivalent diameter D2 of the second-stage bypass channel 220 to the equivalent diameter D1 of the first-stage bypass channel 210 is 0.3 to 0.6.

The ratio of the equivalent diameter of the next-stage branch passage to that of the previous-stage branch passage is 0.3, and the equivalent diameter of the next-stage branch passage is smaller than that of the previous stage, that is, the distance between different groups of needle ribs in the first needle rib array 143 (or the second needle rib array) is small, so that the flow speed of the fluid in the evaporative condenser is reduced, the heat exchange time is prolonged, and the heat of the fluid is better utilized.

The ratio of the equivalent diameter of the next-stage branch channel to that of the previous-stage branch channel is 0.6, the equivalent diameter of the next-stage branch channel is smaller than that of the previous stage, but the spaces between different groups of needle ribs in the first needle rib array 143 (or the second needle rib array) are widened, so that a larger amount of fluid can be accommodated to enter the evaporative condenser, and the heat exchange effect is better.

Referring to FIG. 1, in some embodiments of the present invention, the evaporative condenser 140 is disposed within the power battery pack 130 or on one side of the power battery pack 130, and the evaporative condenser 140 is disposed in parallel with the power batteries within the power battery pack 130, it being understood that the evaporative condenser 140 may be disposed between the power batteries of the power battery pack 130, for example, the evaporative condenser 140 may be disposed on one side of each power battery, or the evaporative condenser 140 may be disposed at intervals of multiple power batteries, or between two power battery packs 130, or on the side of the power battery pack 130, it being contemplated that two power battery packs 130 sandwiching the evaporative condenser 140 may also be considered as a split of one power battery pack 130. The evaporative condenser 140 is arranged in parallel with the power battery, so that the evaporative condenser 140 and the power battery are in the same orientation, and the first inlet and outlet 141 and the second inlet and outlet 142 of the evaporative condenser 140 are parallel to the power battery, so that the flow direction of the fluid can be parallel to the power battery, and the heat exchange can be better carried out. It should be noted that the number of the evaporative condensers 140 may be set according to design requirements, but at least one is provided.

Referring to fig. 5, in some embodiments of the present invention, the evaporative condenser 140 is disposed at one side of the power battery pack 130, and the evaporative condenser 140 is disposed perpendicular to the power batteries in the power battery pack 130, it can be understood that the evaporative condenser 140 is disposed at the middle of two power battery packs 130 or at one side of one power battery pack 130, but the evaporative condenser 140 is also perpendicular to the power batteries, i.e. the first inlet/outlet 141 and the second inlet/outlet 142 of the evaporative condenser 140 are perpendicular to the power batteries, so that the flow direction of the fluid is perpendicular to the power batteries, and heat is more quickly exchanged to the plurality of power batteries, thereby achieving rapid heat dissipation and preheating.

In some embodiments of the present invention, the evaporative condenser 140 is provided in plurality, and the plurality of evaporative condensers 140 are provided in the middle or on one side of the power battery pack 130. For example, a plurality of evaporative condensers 140 are arranged in the middle of the power battery pack 130, i.e. on one side of the power batteries in the power battery pack 130, or two evaporative condensers 140 are arranged at two ends of the power battery pack 130, and an evaporative condenser 140 is continuously arranged on one side of the evaporative condenser 140, i.e. the evaporative condensers 140 are arranged in sequence; an evaporative condenser 140 may also be arranged between the power battery packs 130, for example, a plurality of evaporative condensers 140 are arranged between two power battery packs 130; or a combination of the two ways, so that heat exchange can be performed on a plurality of power battery packs 130.

The following shows the work flow of the power battery thermal management system:

when the power battery pack 130 needs to dissipate heat at a high temperature, the heat of the power battery pack 130 is transferred into the first flat heat pipe 110 and the second flat heat pipe 120 through the upper surface and the lower surface of the power battery pack 130, and is transferred into the evaporative condenser 140 through the heat conduction performance of the first flat heat pipe 110 and the second flat heat pipe 120, so that the heat is taken away by the refrigerant of the evaporative condenser 140, for example, the second inlet/outlet 142 of the evaporative condenser 140 is connected with a vehicle-mounted liquid refrigerant, the liquid refrigerant flows in from the second inlet/outlet 142 of the evaporative condenser 140, and flows out from the first inlet/outlet 141 after being heated to become steam, and finally the heat is released into the environment through the condenser of the vehicle-mounted air conditioning system, and the cooled refrigerant can continuously enter the evaporative condenser 140 to realize circulation. In the process of heat dissipation, the first flat heat pipe 110 and the second flat heat pipe 120 adopt a long evaporation section and a short condensation section, the area of the first flat heat pipe 110 and the second flat heat pipe 120, which exchanges heat with the power battery pack 130, is an evaporation section, and the area of the first flat heat pipe 110 and the second flat heat pipe 120, which exchanges heat with the evaporative condenser 140, is a condensation section, so that the evaporative condenser 140 functions as an evaporator.

When the power battery pack 130 needs to be preheated, the first inlet/outlet 141 of the evaporative condenser 140 is connected to a vehicle-mounted gaseous refrigerant, the refrigerant is heated and gasified by a heating device such as a vehicle-mounted heat pump system, the gaseous refrigerant flows into the evaporative condenser 140 from the first inlet/outlet 141, is cooled, liquefied, releases heat, and flows out from the second inlet/outlet 142, the heat of the refrigerant is transferred to the first flat heat pipe 110 and the second flat heat pipe 120 in the evaporative condenser 140, and is further transferred to the power battery pack 130 under the action of the heat conductivity of the first flat heat pipe 110 and the second flat heat pipe 120, so that the power battery pack 130 can be preheated, and the power battery pack 130 can be maintained within a proper working temperature range. The refrigerant is re-heated and continues to flow into the evaporative condenser 140 to circulate. In the preheating process, the first flat heat pipe 110 and the second flat heat pipe 120 adopt a short evaporation section and a long condensation section, the area of the first flat heat pipe 110 and the second flat heat pipe 120, which exchanges heat with the power battery pack 130, is the condensation section, and the area of the first flat heat pipe 110 and the second flat heat pipe 120, which exchanges heat with the evaporation condenser 140, is the evaporation section, so that the evaporation condenser 140 functions as a condenser.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.