CN112366388A

CN112366388A - Combined type battery cooling device based on phase change material and microchannel

Info

Publication number: CN112366388A
Application number: CN202011241913.4A
Authority: CN
Inventors: 燕嘉宁; 翁建华
Original assignee: Shanghai Electric Power University
Current assignee: Shanghai University of Electric Power; Shanghai Electric Power University; University of Shanghai for Science and Technology
Priority date: 2020-11-09
Filing date: 2020-11-09
Publication date: 2021-02-12

Abstract

The invention provides a combined type battery cooling device based on a phase change material and a micro-channel.

Description

Combined type battery cooling device based on phase change material and microchannel

Technical Field

The invention relates to the technical field of electric vehicle battery thermal management, in particular to a composite battery cooling device based on a phase-change material and a micro-channel.

Background

Electric vehicles are gradually gaining popularity in the market, and compared with fuel vehicles, the advantages of electric vehicles are very obvious: firstly, the electric automobile is more environment-friendly and more economical in energy consumption. However, electric vehicles also have their own short board, i.e., range and battery life. Research shows that the service life of the battery is closely related to the temperature of the battery, if the temperature of the battery is above 50 ℃ throughout the year, the battery loss is obviously accelerated, and the endurance mileage is obviously shortened. In addition, the battery pack has uneven aging caused by too high temperature difference of the battery pack, and the capacity of the whole battery pack is reduced, so the temperature difference of the battery pack should be controlled within 5 ℃, and therefore, an effective heat dissipation system is very necessary to be established for the lithium ion battery pack.

With the maturity of electric automobile technology, people have higher and higher requirements on batteries, however, a series of previous electric automobile spontaneous combustion events cover a layer of shadow for the development of electric automobiles, and one of the reasons is that the electric automobiles generate spontaneous combustion due to heat accumulation caused by thermal runaway in the charging and discharging processes. The importance of the heat dissipation system to the battery was again verified. With the development of battery technology, pure air cooling and liquid cooling cannot meet the requirements of electric vehicles on quick charging, high endurance mileage and the like, and both the two modes have an obvious defect, the temperature of a cooling medium can be gradually increased along with the progress of a cooling process, so that the downstream cooling effect is reduced, and the battery pack has overlarge temperature difference to cause uneven battery aging.

Disclosure of Invention

This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. In this section, as well as in the abstract and the title of the invention of this application, simplifications or omissions may be made to avoid obscuring the purpose of the section, the abstract and the title, and such simplifications or omissions are not intended to limit the scope of the invention.

Therefore, the technical problem to be solved by the present invention is to overcome the defect of excessive temperature difference between the upstream and downstream of battery pack heat dissipation in the prior art, so as to provide a composite battery cooling device based on phase change material and micro-channel.

In order to solve the technical problems, the invention provides the following technical scheme: 1. the utility model provides a combined type battery cooling device based on phase change material and microchannel which characterized in that: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

the fixing assembly comprises a battery mounting frame and a distance adjusting structure arranged on the battery mounting frame; the battery mounting frame comprises a plurality of accommodating grooves, and the distance adjusting structure controls the lengths of the accommodating grooves;

the heat conduction assembly comprises a heat conduction sheet arranged at the end part of the accommodating groove, the heat conduction sheet is provided with a heat conduction surface contacted with the battery, a cooling liquid pore channel and a phase-change material cavity are arranged in the heat conduction sheet, and the cooling liquid pore channel is arranged on one side of the phase-change material cavity and exchanges heat with the phase-change material cavity;

and the circulating assembly comprises cooling liquid collecting valves connected with the heat-conducting fins and runoff pipelines connected with the cooling liquid collecting valves.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the phase-change material cavity is provided with one side adjacent to the heat-conducting surface, and the cooling liquid pore passages are distributed on one side of the phase-change material cavity.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the cooling liquid channel is a square micro-channel, the phase change material cavity is a strip-shaped closed cavity, and the cooling liquid channel is arranged along the length direction of the strip-shaped closed cavity and penetrates through the heat conducting sheet.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the cooling liquid channel also comprises end channels arranged at the upper end and the lower end of the phase change material cavity; the end channels are arranged along the length direction of the elongated closed cavity.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the cooling liquid flow collecting valve comprises an inlet flow collecting valve and an outlet flow collecting valve which are respectively arranged at two ends of the heat conducting fin, and the cooling liquid channel is simultaneously communicated with the inlet flow collecting valve and the outlet flow collecting valve.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the runoff pipeline comprises a flow dividing pipe and a flow collecting pipe, the flow dividing pipe is communicated with each inlet flow collecting valve, the flow collecting pipe is communicated with each outlet flow collecting valve, and the flow dividing pipe is connected with the water pump and is independent of the flow collecting pipe.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the circulating assembly further comprises a temperature sensor arranged on one side, close to the outlet current collecting valve, of the battery mounting frame and in contact with a battery closest to the outlet current collecting valve.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: two rows of parallel accommodating grooves are formed in the battery mounting frame, two surfaces of the heat conducting fins positioned in the middle of the accommodating grooves are heat conducting surfaces, and each side heat conducting surface is adjacent to one phase change material cavity.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the distance adjusting structure comprises linkage pieces and driving pieces, the linkage pieces are connected with the heat conducting fins, the driving pieces are arranged between the linkage pieces, the linkage pieces are arranged in parallel along the battery placing direction, and the driving pieces drive the linkage pieces to be close to or far away from each other.

As a preferable scheme of the composite battery cooling device based on the phase change material and the micro-channel, the composite battery cooling device comprises: the linkage piece is the straight line rack, the parallel crisscross distribution of straight line rack, the driving piece is drive gear, drive gear sets up between the straight line rack and with each the straight line rack toothing, still be equipped with adjust knob on the drive gear.

The invention has the beneficial effects that: according to the combined type battery cooling device based on the phase change material and the micro-channel, the phase change material cavity is arranged in the heat conducting fin, the problem of overhigh temperature difference of the battery pack can be effectively solved by utilizing the characteristics that the phase change material has high latent heat, the temperature is relatively stable in the phase change process and the like, and the temperature of the battery can be effectively controlled by matching with the micro-channel heat exchanger.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise. Wherein:

FIG. 1 is a schematic diagram of the overall structure of a composite battery cooling device based on phase change materials and micro-channels;

FIG. 2 is a schematic diagram of the operation of a hybrid battery cooling device based on phase change materials and microchannels;

FIG. 3 is a schematic cross-sectional view of a thermally conductive sheet;

FIG. 4 is a schematic cross-sectional view of an intermediate thermally conductive sheet;

fig. 5 is a schematic view of a distance adjustment structure.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Example 1

The present embodiment provides a hybrid battery cooling device based on phase change material and micro-channels, which has a structure as shown in fig. 1-5, and includes a fixing member 100, a heat conducting member 200, and a circulating member 300.

Wherein, fixed subassembly 100 is used for installing square battery 400, including battery installing frame 110 and locate the distance adjustment structure 120 on battery installing frame 110, battery installing frame 110 includes a plurality of storage tanks 111, and square battery 400 places in storage tank 111 according to the square arrangement that the long limit is parallel, and distance adjustment structure 120 is used for controlling the length of storage tank 111 to the battery of the different models of adaptation.

The end portions of the heat conducting assembly 200 and the square battery 400 are in direct contact for absorbing and transferring heat generated by the square battery 400, the heat conducting assembly comprises a heat conducting sheet 210 arranged at the end portion of the accommodating groove 111, the heat conducting sheet 210 is provided with a heat conducting surface 211 in contact with the battery, a cooling liquid pore passage and a phase change material cavity 220 are formed in the heat conducting sheet 210, and the cooling liquid pore passage is arranged on one side of the phase change material cavity 220 and exchanges heat with the phase change material cavity 220.

The circulation assembly 300 is connected to the heat-conducting fins 210, and is used for circulating the coolant in the heat-conducting fins 210, and includes coolant collecting valves connected to the respective heat-conducting fins 210, and radial flow pipes connected to the respective coolant collecting valves.

Preferably, the heat conducting plate 210 in this embodiment is made of aluminum, which has good thermal conductivity, and the phase-change material is made of paraffin, which is hermetically stored in the phase-change material cavity 220. When the temperature of the battery is low, paraffin can be used for absorbing heat to generate phase change, and at the moment, the paraffin starts to melt and the temperature does not rise any more. In the whole heat absorption process, the temperature of the paraffin is kept in a stable range and cannot be greatly increased. Then, the paraffin transmits the heat to the aluminum heat conducting fin 210, and finally, the surface of the aluminum heat conducting fin 210 transmits the heat to the external environment in a natural convection mode.

When the square battery 400 generates more heat due to high-power discharge, the heat dissipation requirement cannot be met by only depending on paraffin. At this time, the cooling liquid in the cooling liquid channel 230 starts to operate, and the cooling liquid flows in the channel at a certain speed to take away the heat in the phase change material cavity 220, so as to prevent the temperature from greatly rising after the paraffin is completely melted. In this case, the paraffin wax mainly serves to prevent the temperature of the battery pack from being unevenly distributed.

The combined type battery cooling device based on phase change material and microchannel that this embodiment provided utilizes phase change material to have high latent heat through set up phase change material chamber 220 in conducting strip 210 to and characteristics such as phase transition in-process temperature relatively stable can effectively solve the too high problem of group battery difference in temperature, and cooperation microchannel heat exchanger can effectively control the battery temperature.

Example 2

The embodiment provides a combined type battery cooling device based on phase change material and microchannel, its characterized in that: the fixing assembly 100 comprises a battery mounting frame 110 and a distance adjusting structure 120 arranged on the battery mounting frame 110; the battery mounting frame 110 includes a plurality of receiving grooves 111, and the distance adjusting structure 120 controls the length of the receiving grooves 111; the heat conducting assembly 200 comprises a heat conducting sheet 210 arranged at the end part of the accommodating groove 111, the heat conducting sheet 210 is provided with a heat conducting surface 211 contacted with the battery, a cooling liquid pore passage and a phase change material cavity 220 are arranged in the heat conducting sheet 210, and the cooling liquid pore passage is arranged at one side of the phase change material cavity 220 and exchanges heat with the phase change material cavity 220; the circulation assembly 300 includes coolant collecting valves connected to the respective heat-transfer fins 210, and a radial flow pipe connected to the respective coolant collecting valves.

As shown in fig. 2, when the prismatic battery 400 is placed in the battery mounting frame 110, two ends of the prismatic battery 400 respectively contact with one of the heat-conducting sheets 210, the same end of one column of the prismatic batteries 400 contacts with the same heat-conducting sheet 210, and the phase change material and the cooling liquid in the heat-conducting sheet 210 perform heat exchange and transfer, so that the temperature of each battery in one column of the battery pack can be kept substantially the same, and the overheating of the downstream battery can be avoided.

As shown in fig. 1 and fig. 3, the phase-change material cavity 220 in this embodiment has one side adjacent to the heat conducting surface 211, the cooling liquid pore channels are distributed on one side of the phase-change material cavity 220, and a heat conducting silicone grease is further coated between the square battery 400 and the heat conducting surface 211 to fill up a small gap between the square battery 400 and the heat conducting sheet 210, so that the heat of the square battery 400 can be sufficiently transferred to the heat conducting sheet 210.

Specifically, the cooling liquid channel 230 is a square micro-channel, the phase change material cavity 220 is a strip-shaped closed cavity, and the cooling liquid channel 230 is arranged along the length direction of the strip-shaped closed cavity and penetrates through the heat conducting sheet 210. The phase-change material is preferably paraffin, has the characteristics of low cost and easy maintenance, and the phase-change temperature is suitable for the working temperature range of the battery.

When the battery works under a low charge-discharge multiplying power, the generated heat is small, and the heat dissipation requirement can be met only by paraffin. When the temperature reaches 44 ℃ of the phase transition temperature when the paraffin absorbs more heat, the paraffin begins to melt into a liquid phase, and the temperature of the paraffin is slightly higher than 44 ℃ at the moment, and the temperature of the paraffin is relatively stable at the moment.

Along with the increase of the charge-discharge multiplying power, the liquid fraction of the paraffin is increased, the temperature is also increased, and the heat dissipation requirement cannot be met only by the paraffin. At this time, the coolant in the circulation assembly 300 starts to flow, and the temperature of the paraffin in the phase change material chamber 220 is lowered to keep the temperature of the paraffin at 44 ℃ or below 44 ℃.

In order to further transmit heat to the paraffin in the phase-change material cavity 220, end channels 231 are further arranged at the upper end and the lower end of the phase-change material cavity 220; the end channels 231 are arranged along the length direction of the elongated closed cavity to complete the omni-directional heat dissipation of the phase change material cavity 220.

Specifically, the cooling liquid in this embodiment is selected as water, and is driven by the water pump to circularly flow, and the flow rate of the cooling water in the microchannel can be controlled by adjusting the rotation speed of the water pump.

As shown in fig. 1, the coolant collecting valve at the end of the heat conducting sheet 210 includes an inlet collecting valve 310 and an outlet collecting valve 320, which are respectively disposed at two ends of the heat conducting sheet 210, the coolant channel 230 inside the heat conducting sheet 210 is simultaneously communicated with the inlet collecting valve 310 and the outlet collecting valve 320, and the inlet collecting valve 310 distributes the coolant to each square micro channel in the heat conducting sheet 210, so that the coolant can uniformly flow through the whole heat conducting sheet 210, and the heat received by the heat conducting sheet 210 is taken away, so as to keep the temperature of the phase change material stable.

As shown in fig. 1, the radial flow pipeline in this embodiment includes a flow dividing pipe 330 and a flow collecting pipe 340, the flow dividing pipe 330 is communicated with each inlet flow collecting valve 310, the flow collecting pipe 340 is communicated with each outlet flow collecting valve 320, respectively, and the flow dividing pipe 330 is connected to the water pump and is independent from the flow collecting pipe 340.

When the square battery 400 works under a high charge-discharge rate, the generated heat is more, and the heat dissipation requirement cannot be met by only depending on paraffin. At this time, the water pump starts to operate, and the coolant flows at a constant speed in the microchannel. The coolant in the coolant channels 230 on the upper and lower sides of the phase-change material cavity 220 can directly take away the heat generated by the battery, and the coolant channels 230 on the left or right side of the phase-change material cavity 220 mainly function to cool the paraffin, so that the temperature of the paraffin is prevented from greatly rising after the paraffin is completely melted. In this case, the paraffin wax mainly serves to prevent the temperature of the battery pack from being unevenly distributed.

When the charge-discharge multiplying power is continuously increased, the rotating speed of the water pump is increased, and the heat dissipation characteristic is enhanced by increasing the flowing speed of the cooling water.

In order to prevent the temperature of the battery downstream of the cooling fluid from being too high, the circulation assembly 300 of the present embodiment is further provided with a temperature sensor 350, and the temperature sensor 350 is disposed on a side of the battery mounting frame 110 close to the outlet manifold valve 320 and is in contact with a battery closest to the outlet manifold valve 320 for monitoring the temperature of the battery in real time. And the control system of the water pump is connected to the temperature sensor 350, which can adjust the rotation speed of the water pump according to the monitored battery temperature.

When the charge-discharge rate is suddenly reduced, the battery may still be at a higher temperature, and at this time, the temperature sensing device needs to be matched, and when the temperature is still higher, the battery pack still needs to be cooled by a higher flow rate of the cooling liquid. As the temperature is gradually reduced, the coolant flow rate may be gradually reduced.

As shown in fig. 2, the square cells 400 in this embodiment are provided with two rows, so the heat conducting strip 210 in the middle of the two rows of cells needs to be contacted with two cells at the same time, and as shown in fig. 4, both sides of the heat conducting strip 210 in the middle are heat conducting surfaces 211, the inner part is provided with two phase change material cavities 220, each side heat conducting surface 211 is adjacent to one phase change material cavity 220, and the cooling liquid level channel is arranged in the middle of the two phase change material cavities 220, and at the upper end and the lower end.

As shown in fig. 5, the distance adjustment structure 120 in this embodiment includes link members 121 connecting the respective heat conductive sheets 210, and driving members 122 provided between the link members 121, the link members 121 being arranged in parallel along the battery placement direction, the driving members 122 driving the link members 121 to approach or separate from each other. Under the action of the distance adjusting structure 120, the distance between the two heat-conducting fins 210 can be adjusted to adapt to batteries of different sizes.

Specifically, the linkage member 121 in this embodiment is a linear rack 121a, the linear racks 121a are distributed in parallel and staggered, the driving member 122 is a driving gear 122a, the driving gear 122a is disposed between the linear racks 121a and engaged with each linear rack 121a, and the driving gear 122a is further provided with an adjusting knob 122 b. By rotating the adjusting knob 122b, the two linear racks 121a can be driven to move linearly relatively, so that the function of distance adjustment is realized.

It is important to note that the construction and arrangement of the present application as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters (e.g., temperatures, pressures, etc.), mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in this application. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of this invention. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present inventions. Therefore, the present invention is not limited to a particular embodiment, but extends to various modifications that nevertheless fall within the scope of the appended claims.

Moreover, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not be described (i.e., those unrelated to the presently contemplated best mode of carrying out the invention, or those unrelated to enabling the invention).

It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.

It should be noted that the above-mentioned embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.

Claims

1. The utility model provides a combined type battery cooling device based on phase change material and microchannel which characterized in that: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

the fixing assembly (100) comprises a battery mounting frame (110) and a distance adjusting structure (120) arranged on the battery mounting frame (110); the battery mounting frame (110) comprises a plurality of accommodating grooves (111), and the distance adjusting structure (120) controls the length of the accommodating grooves (111);

the heat conduction assembly (200) comprises a heat conduction sheet (210) arranged at the end part of the accommodating groove (111), the heat conduction sheet (210) is provided with a heat conduction surface (211) contacted with a battery, a cooling liquid pore channel and a phase change material cavity (220) are arranged in the heat conduction sheet (210), and the cooling liquid pore channel is arranged on one side of the phase change material cavity (220) and exchanges heat with the phase change material cavity (220);

and the circulating assembly (300) comprises a cooling liquid collecting valve connected with each heat-conducting fin (210) and a radial flow pipeline connected with each cooling liquid collecting valve.

2. The phase change material and microchannel-based composite battery cooling apparatus of claim 1, wherein: the phase-change material cavity (220) is provided with one side adjacent to the heat-conducting surface (211), and the cooling liquid pore passages are distributed on one side of the phase-change material cavity (220).

3. The phase change material and microchannel-based composite battery cooling apparatus of claim 2, wherein: the cooling liquid channel (230) is a square micro-channel, the phase change material cavity (220) is a strip-shaped closed cavity, and the cooling liquid channel (230) is arranged along the length direction of the strip-shaped closed cavity and penetrates through the heat conducting sheet (210).

4. The phase change material and microchannel-based composite battery cooling apparatus of claim 3, wherein: the cooling liquid channel (230) also comprises end channels (231) arranged at the upper end and the lower end of the phase-change material cavity (220); the end channels (231) are arranged along the length of the elongate closed chamber.

5. The phase change material and microchannel-based composite battery cooling apparatus of claim 4, wherein: the cooling liquid collecting valve comprises an inlet collecting valve (310) and an outlet collecting valve (320) which are respectively arranged at two ends of the heat conducting sheet (210), and the cooling liquid channel (230) is simultaneously communicated with the inlet collecting valve (310) and the outlet collecting valve (320).

6. The phase change material and microchannel-based composite battery cooling apparatus of claim 5, wherein: the runoff pipeline comprises a flow dividing pipe (330) and a flow collecting pipe (340), the flow dividing pipe (330) is communicated with each inlet flow collecting valve (310), the flow collecting pipe (340) is communicated with each outlet flow collecting valve (320), and the flow dividing pipe (330) is connected with a water pump and is independent of the flow collecting pipe (340).

7. The phase change material and microchannel-based composite battery cooling apparatus of claim 6, wherein: the circulation assembly (300) further comprises a temperature sensor (350) which is arranged on one side of the cell mounting frame (110) close to the outlet collecting valve (320) and is in contact with a cell closest to the outlet collecting valve (320).

8. The phase change material and microchannel-based composite battery cooling apparatus of any one of claims 1-7, wherein: two rows of parallel accommodating grooves (111) are arranged in the battery mounting frame (110), two surfaces of a heat conducting sheet (210) positioned in the middle of the accommodating grooves (111) are heat conducting surfaces (211), and each side heat conducting surface (211) is adjacent to one phase change material cavity (220) respectively.

9. The phase change material and microchannel-based composite battery cooling apparatus of claim 8, wherein: the distance adjusting structure (120) comprises linkage pieces (121) connecting the heat conducting sheets (210) and driving pieces (122) arranged between the linkage pieces (121), the linkage pieces (121) are arranged in parallel along the battery placement direction, and the driving pieces (122) drive the linkage pieces (121) to approach or separate from each other.

10. The phase change material and microchannel-based composite battery cooling apparatus of claim 9, wherein: the linkage piece (121) is linear racks (121a), the linear racks (121a) are distributed in a parallel and staggered mode, the driving piece (122) is a driving gear (122a), the driving gear (122a) is arranged between the linear racks (121a) and meshed with the linear racks (121a), and an adjusting knob (122b) is further arranged on the driving gear (122 a).