Lightweight controllable temperature battery thermal management system and implementation method thereof

Abstract

The application discloses a light-weight controllable-temperature battery thermal management system, which comprises batteries, a battery module formed by series and parallel connection of the batteries, composite phase change materials, microchannels, interface phase change materials and heating films; the battery module is arranged in staggered rows and in a honeycomb shape; the composite phase change materials are wrapped around the outer circumferential surfaces of the batteries and directly contact the batteries; the microchannels are arranged in layers and longitudinally on the outer circumferential surfaces of the composite phase change materials, the microchannels are in a honeycomb grid shape and surround each battery, one end edge of each microchannel is provided with a water inlet, the other end edge of each microchannel is provided with a water outlet, and adjacent microchannels are connected by support frames; the interface phase change materials cover the battery tabs, and the heating films are fixed to the other surfaces of the interface phase change materials; the application has the advantages of simple structure, high safety and convenience of power battery design, light-weight design in the power battery design, reduced cost of system construction, double functions of high-temperature heat dissipation and low-temperature heating, and wide application space.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery thermal management, in particular to a light-weight controllable-temperature battery thermal management system and an implementation method thereof. BACKGROUND

[0002] The power battery is a core component of a new energy vehicle, and its design and performance are very important. When the power battery is charging and discharging, a large amount of heat will be released. If the heat is not discharged in time, great safety hazards will be caused. At the same time, when the ambient temperature is too low, the performance of the battery will also be greatly limited. Therefore, the battery thermal management technology and the battery thermal safety have attracted widespread attention. The thermal management target is to control the temperature of the battery so that the battery can continuously exert the best performance in a reasonable temperature range.

[0003] At present, due to the demand for energy emission reduction, a medium or large battery module in which multiple battery units are linked needs to be manufactured to have the smallest size and weight possible, that is, the integration of the stacked battery units in the battery module needs to be continuously improved. Therefore, there is a trend of designing a light-weight battery module. However, both the air cooling device and the liquid cooling device have a great demand for space. Therefore, a phase change material cooling technology can greatly utilize the space, so that the volume of the battery thermal management module is reduced to the maximum. However, the phase change material has limitations such as weak overall structural strength after phase change and quality hazards. Therefore, a single traditional cooling technology gradually cannot meet the thermal management demand. In order to achieve a safe, economical and efficient battery thermal management target, it is necessary to seek an optimal thermal management system. Therefore, the present application provides a light-weight controllable-temperature battery thermal management system and an implementation method thereof. SUMMARY

[0004] The present application aims to overcome the shortcomings and deficiencies of the prior art, and provides a light-weight controllable-temperature battery thermal management system and an implementation method thereof. The liquid cooling and the phase change material cooling are coupled together, the dual functions of high-temperature heat dissipation and low-temperature heating are taken into account, and the composite phase change material, the microchannel, the interface phase change material and the heating film are arranged to solve the problems in the background technology.

[0005] The purpose of the present application is achieved by the following technical solutions:

[0006] The application discloses a light-weight controllable-temperature battery thermal management system, which comprises batteries, a battery module formed by series and parallel connection of the batteries, composite phase change materials, microchannels, interface phase change materials and heating films; the battery module is arranged in a staggered manner and in a honeycomb shape; the composite phase change materials are wrapped around outer circumferential surfaces of the batteries and are in direct contact with the batteries; the microchannels are arranged in layers and in a longitudinal direction on outer circumferential surfaces of the composite phase change materials, the microchannels are in a honeycomb grid shape and surround each battery, one end edge of the microchannels is provided with a water inlet, the other end edge of the microchannels is provided with a water outlet, and adjacent microchannels in the upper and lower layers are connected by support frames; and the interface phase change materials cover battery tabs, and the interface phase change materials are fixed with the heating films on another surface.

[0007] Further, the microchannels in the honeycomb grid shape connect the single battery heat dissipation modules in series, and the battery modules in each row are connected in parallel to form the honeycomb battery thermal management system; and the working medium rapidly diffuses in the microchannels and exchanges heat with the phase change materials.

[0008] Further, the microchannels comprise first microchannels and second microchannels, the first microchannels are horizontally arranged on the outer circumferential surfaces of the composite phase change materials, and the layers are not connected.

[0009] Further, the second microchannels are inclined from the water inlet to the water outlet, the water inlet and the water outlet are connected with the second microchannels in each layer through connecting pipelines, the water inlet is arranged at the highest point of the second microchannels, and the water outlet is arranged at the lowest point of the second microchannels.

[0010] Further, the interface phase change materials are provided with through holes, the through holes are sleeved in the top end tabs of the batteries, so that the interface phase change materials are more attached to the upper surfaces of the batteries.

[0011] Further, the composite phase change materials are in a six-sided hollow column structure, and the outer edges are limited by the microchannels in the honeycomb grid shape and the support frames.

[0012] As a preferred scheme, the composite phase change materials adopt insulation type, flame-retardant type and three-dimensional high-thermal-conductivity skeleton composite phase change materials, specifically metal foams, porous polymers, carbon-based three-dimensional porous materials and porous ceramic materials.

[0013] As a preferred scheme, the interface phase change materials adopt high-thermal-conductivity phase change interface materials, specifically indium-based alloy thermal conductive gaskets, liquid metal thermal conductive agents, graphene thermal conductive films / gaskets and carbon fiber thermal conductive gaskets.

[0014] As a preferred scheme, the support frames are made of high-thermal-conductivity metal materials, specifically copper.

[0015] As a preferred scheme, the heating films are made of semiconductor materials or components with a large positive temperature coefficient, specifically resistance wires or PTC heating films.

[0016] As a preferred scheme, the liquid cooling working medium in the micro-channel is air, liquid water, ethylene glycol and gallium-based alloy liquid metal when high temperature heat dissipation, and the working medium is boiling water when low temperature heating.

[0017] The application also provides an implementation method of the light-weight controllable temperature battery thermal management system, comprising:

[0018] When the system works in a high temperature environment, a large amount of heat generated in the process of battery charging and discharging causes the temperature of the battery pack to continuously rise, and the generated heat is transferred to the composite phase change material and the interface phase change material; among the heat transferred to the composite phase change material, a first part of the heat is absorbed by the phase change material and then phase changes; a second part of the heat exchanges heat with the liquid cooling working medium in the micro-channel, the liquid cooling working medium is air, liquid water, ethylene glycol and gallium-based alloy liquid metal, and the second part of the heat is finally taken away by the liquid cooling working medium; finally, a third part of the heat remaining is lost to the outside through the support frame of the high-thermal-conductivity copper plate; secondly, the heat generated by the battery tab is transferred to the interface phase change material, and finally exchanged with air convection to dissipate heat;

[0019] When the system works in a low temperature environment, the working medium in the micro-channel is changed to boiling water; and the heating film on the surface of the interface phase change material preheats the battery, so that the temperature consistency of the battery module is ensured in the low temperature preheating process.

[0020] Compared with the prior art, the application has the following beneficial effects:

[0021] The battery thermal management system of the application couples liquid cooling and phase change material cooling together, has the dual functions of high temperature heat dissipation and low temperature heating, and through the setting of the battery module arranged in a staggered manner and in a honeycomb shape, the composite phase change material is wrapped around the outer circumferential surface of the battery and directly contacts the battery; the micro-channels are arranged in layers and longitudinally on the outer circumferential surface of the composite phase change material, the micro-channels are in a honeycomb grid shape and surround each battery; the honeycomb grid-shaped micro-channels are used to limit and fix the battery module, which is different from the traditional box body and has good stability, compact structure and space saving, and achieves the effect of light weight; the honeycomb structure is also used, the diffusion path is fast during the working medium conveying process of the micro-channels, the transferred heat is balanced, and the temperature consistency between the batteries can be ensured whether it is high temperature heat dissipation or low temperature heating; the second micro-channels are arranged in an inclined manner and connected pipes are arranged between the layers to communicate, the working medium conveying speed is accelerated, and the overall temperature control effect of the thermal management system is improved; the application has a simple structure, meets the high safety and convenience of the design of the power battery, highlights the light weight design in the design of the power battery, can greatly reduce the cost of system construction, has the dual functions of high temperature heat dissipation and low temperature heating, and has a wide application space. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a schematic diagram of the overall structure of the present application;

[0023] Figure 2 is a schematic diagram of the overall structure of the present application;

[0024] Figure 3 is a schematic diagram of the overall structure of the present application;

[0025] Figure 4 is a schematic diagram of the overall structure of the present application;

[0026] Figure 5 is a schematic diagram of the overall structure of the present application;

[0027] Figure 6 is a schematic diagram of the overall structure of the present application;

[0028] Figure 7 is a schematic diagram of the overall structure of the present application;

[0029] In the figure: 1, battery; 2, composite phase change material; 3, first microchannel; 3-1, second microchannel; 4, support frame; 5, interface phase change material; 5-1, through hole; 6, heating film; 7, water inlet; 8, water outlet; 9, connecting pipeline. DETAILED DESCRIPTION

[0030] The present application will be further described in conjunction with the embodiments and the accompanying drawings, but the embodiments of the present application are not limited thereto.

[0031] Example 1:

[0032] Please refer to Figures 1-7 , the embodiment provides a technical solution:

[0033] A light-weight controllable temperature battery thermal management system, comprising a battery 1, the battery 1 is connected in series and parallel to form a battery module, further comprising a composite phase change material 2, a microchannel, an interface phase change material 5 and a heating film 6; the battery module is staggered and arranged, and is in the shape of a honeycomb; the composite phase change material 2 is wrapped around the outer circumferential surface of the battery 1 and directly contacts the same; the microchannel is arranged in layers and longitudinally on the outer circumferential surface of the composite phase change material 2, the microchannel is in the shape of a honeycomb grid and surrounds each battery 1, one end edge of the microchannel is provided with a water inlet 7, the other end edge is provided with a water outlet 8, and the upper and lower adjacent microchannels are connected by a support frame 4; the interface phase change material 5 covers the tab of the battery 1, and the other surface of the interface phase change material 5 is fixed with the heating film 6.

[0034] The battery thermal management system of the application couples liquid cooling and phase change material cooling together, and has the dual functions of high-temperature heat dissipation and low-temperature heating, through setting the battery module in staggered arrangement and in honeycomb shape, the composite phase change material 2 is wrapped around the outer peripheral surface of the battery 1 and directly contacts with the battery 1, the micro-channel is arranged in layers and longitudinally on the outer peripheral surface of the composite phase change material 2, the micro-channel is in honeycomb grid shape and surrounds each battery 1, the honeycomb grid-shaped micro-channel is used for limiting and fixing the battery module, which is different from the traditional box body and has good stability, compact structure and space saving, and achieves the effect of light weight; the diffusion path of the working medium in the micro-channel is fast during the conveying process, the transferred heat is balanced, and the temperature consistency between the batteries 1 can be guaranteed in high-temperature heat dissipation or low-temperature heating; the application has simple structure, high safety and convenience in the design of power battery, highlights the light weight design in the design of power battery, can greatly reduce the cost of system construction, and has the dual functions of high-temperature heat dissipation and low-temperature heating, and has wide application space.

[0035] As shown in Figures 1-3 , in order to further ensure the structural stability of the device, the honeycomb grid-shaped micro-channel is used for connecting the single batteries 1 in the heat dissipation module into rows, the battery modules in each row are connected in parallel into the honeycomb type battery thermal management system, and the working medium rapidly diffuses in the micro-channel and exchanges heat with the phase change material; the thermal management system of the embodiment adopts a plurality of single batteries 1 in the hexagonal column heat dissipation module to link the honeycomb type battery thermal management system, the honeycomb structure has good stability, and each unit is independently and conveniently disassembled and repaired, so that the high safety and convenience in the design of power battery are met.

[0036] In the embodiment 1, the micro-channel includes a first micro-channel 3 and a second micro-channel 3-1, as shown in Figure 1 and Figure 2 , the first micro-channel 3 is adopted in the embodiment 1, the first micro-channel 3 is horizontally arranged on the outer peripheral surface of the composite phase change material 2, and there is no communication between the layers. The first micro-channel 3 is assembled in multiple layers, each layer is provided with an inlet / outlet 8, and each layer of the micro-channel can work independently; the first micro-channel 3 is a hexagonal pipeline and surrounds each battery 1, exchanges the same heat for each battery 1, and keeps the temperature of the battery module consistent; the hexagonal pipeline has compact structure, the diffusion path of the working medium is fast, the working medium uniformly flows through each single battery 1, which is different from the traditional liquid cooling technology and is not affected by the number of channels, flow rate and flow direction, the occupied space is greatly reduced, and the purpose of light weight of the thermal management system is achieved.

[0037] Embodiment 2:

[0038] As shown in Figure 4 and Figure 5As shown, the structure of Embodiment 2 is basically the same as that of Embodiment 1, except that the microchannels are different. Embodiment 2 uses a second microchannel 3-1, specifically: the second microchannel 3-1 is inclined from the inlet 7 to the outlet 8. The inlet 7 and the outlet 8 are connected to the second microchannel 3-1 of each layer through the connecting pipe 9. The inlet 7 is located at the highest point of the second microchannel 3-1, and the outlet 8 is located at the lowest point of the second microchannel 3-1. Considering the flow rate and direction of the working medium, the second microchannel 3-1 is inclined compared to the first microchannel 3, which avoids backflow when the working medium flows and further accelerates the diffusion speed of the working medium.

[0039] The following is a further explanation of the parts that are the same in Examples 1 and 2:

[0040] like Figure 4 As shown, the interface phase change material 5 is provided with a through hole 5-1, which is fitted into the top tab of the battery 1, so that the interface phase change material 5 fits the upper surface of the battery 1 better. The purpose of the through hole 5-1 is: 1. to make the interface phase change material 5 fit better; 2. to make the heating film 6 directly contact the battery 1.

[0041] like Figure 6 As shown, the composite phase change material 2 has a hexagonal hollow cylindrical structure, with its outer edge constrained by honeycomb-like microchannels and the supporting frame 4. In this embodiment, the composite phase change material 2 provides full-surround contact with the battery 1, further enhancing the thermal conductivity.

[0042] To improve the heat dissipation efficiency of the single cell 1, the composite phase change material 2 adopts an insulating, flame-retardant, and three-dimensional high thermal conductivity framework composite phase change material, specifically metal foam, porous polymer, carbon-based three-dimensional porous material, and porous ceramic material, including: metal foam (foamed copper, foamed aluminum, foamed nickel) / paraffin / graphite composite phase change material, paraffin / nano flame retardant composite phase change material, paraffin / carbon nanotube high thermal conductivity composite phase change material, paraffin / graphene high thermal conductivity composite phase change material, graphene-coated foamed nickel and paraffin composite phase change material, porous SiC ceramic / paraffin composite phase change material, etc.

[0043] To accelerate heat dissipation at the tab of battery 1, the interface phase change material 5 adopts a high thermal conductivity phase change interface material, specifically an indium-based alloy thermal pad, a liquid metal thermal conductive agent, a graphene thermal conductive film / pad, or a carbon fiber thermal pad.

[0044] To improve the heat dissipation efficiency of the thermal management system, the support frame 4 is made of a high thermal conductivity metal material, specifically copper. In addition to the support frame 4, the microchannels in this embodiment are also made of high thermal conductivity metals such as copper, which have good pressure resistance, giving the battery 1 high stability and good mechanical strength.

[0045] In the embodiment, the heating film 6 material adopts a semiconductor material or component with a large positive temperature coefficient, specifically, a resistance wire or a PTC heating film; the heating film 6 of the embodiment is composed of a single-layer resistance wire, a square shell and a lead wire, the arrangement of the heating resistance wire passes through the center of each battery cell, the resistance wire is relatively thin, is assembled in the square shell and is conducted by the lead wire.

[0046] In order to improve the heat dissipation and heating efficiency of the single battery 1, the liquid cooling working medium in the microchannel is air, liquid water, ethylene glycol and gallium-based alloy liquid metal when high-temperature heat dissipation, and the working medium is boiling water when low-temperature heating.

[0047] On the basis of the above technical scheme, the embodiment further provides an implementation method of the light-weight controllable-temperature battery thermal management system, comprising:

[0048] When the system works in a high-temperature environment, a large amount of heat generated in the charging and discharging process of the battery 1 causes the temperature of the battery pack to continuously rise, and the generated heat is transferred to the composite phase change material 2 and the interface phase change material 5; among the heat transferred to the composite phase change material 2, a first part of the heat is absorbed by the phase change material and undergoes phase change; a second part of the heat exchanges heat with the liquid cooling working medium in the microchannel, the liquid cooling working medium is air, liquid water, ethylene glycol and gallium-based alloy liquid metal, and the second part of the heat will finally be taken away by the flowing liquid cooling working medium; finally, a third part of the remaining heat is lost to the outside through the support frame 4 of the high-heat-conducting copper plate; secondly, the heat generated by the tab of the battery 1 is transferred to the interface phase change material 5, and finally exchanges heat with air convection to dissipate heat;

[0049] When the system works in a low-temperature environment, the working medium in the microchannel is changed to boiling water; the heating film 6 on the surface of the interface phase change material 5 preheats the battery 1, so as to ensure the temperature consistency of the battery module during the low-temperature preheating process.

[0050] The above is the preferred embodiment of the present application, but the embodiment of the present application is not limited by the above, any change, modification, replacement, combination, simplification made without departing from the spirit and principles of the present application shall be an equivalent replacement mode, and all shall be included in the protection scope of the present application.

Claims

1. A light-weight temperature-controllable battery thermal management system, comprising batteries, the batteries are connected in series and parallel to form a battery module, characterized in that, The battery module is staggered and arranged in a honeycomb shape; the composite phase change material is wrapped around the outer circumferential surface of the battery and directly contacts the battery; the microchannels are arranged in layers and longitudinally on the outer circumferential surface of the composite phase change material, the microchannels are arranged in a honeycomb grid shape and surround each battery, one end edge of the microchannels is provided with a water inlet, the other end edge is provided with a water outlet, and adjacent microchannels are connected by a support frame; the interface phase change material covers the battery tab, and the other surface of the interface phase change material is fixed with a heating film. When high-temperature heat dissipation, the liquid cooling medium in the microchannel is air, liquid water, ethylene glycol and gallium-based alloy liquid metal, and when low-temperature heating, the medium is boiling water.

2. The battery thermal management system of claim 1, wherein, The honeycomb grid-shaped microchannels connect the single battery heat dissipation modules in series, and the battery modules are connected in parallel to form a honeycomb battery thermal management system, and the medium rapidly diffuses in the microchannels and exchanges heat with the phase change material.

3. The battery thermal management system of claim 1, wherein, The microchannel includes a first microchannel and a second microchannel, the first microchannel is horizontally arranged on the outer circumferential surface of the composite phase change material, and there is no communication between layers.

4. The battery thermal management system of claim 3, wherein, The second microchannel is inclined from the water inlet to the water outlet, the water inlet and the water outlet are connected with the second microchannel of each layer through a connecting pipeline, the water inlet is arranged at the highest point of the second microchannel, and the water outlet is arranged at the lowest point of the second microchannel.

5. The battery thermal management system of claim 1, wherein, The interface phase change material is provided with a through hole, the through hole is sleeved in the battery top tab, so that the interface phase change material is more fitted to the upper surface of the battery.

6. The battery thermal management system of claim 1, wherein, The composite phase change material is a hollow column structure with a hexagonal shape, and the outer edge is limited by the honeycomb grid-shaped microchannel and the support frame.

7. The battery thermal management system of claim 1, wherein, The interface phase change material adopts a high-thermal-conductivity phase change interface material, specifically an indium-based alloy thermal conductive gasket, a liquid metal thermal conductive agent, a graphene thermal conductive film / gasket, and a carbon fiber thermal conductive gasket.

8. The battery thermal management system of claim 1, wherein, The support frame is made of high-thermal-conductivity metal material.

9. The battery thermal management system of claim 1, wherein, The support frame is made of copper.

10. A method for implementing the battery thermal management system of any one of claims 1 to 9, characterized in that, The system includes: When the system works in a high-temperature environment, a large amount of heat generated in the battery charging and discharging process causes the temperature of the battery pack to rise continuously, and the generated heat is transferred to the composite phase change material and the interface phase change material; among the heat transferred to the composite phase change material, a first part of the heat is absorbed by the phase change material and undergoes phase change; a second part of the heat exchanges heat with the liquid cooling medium in the microchannel, the liquid cooling medium is air, liquid water, ethylene glycol and gallium-based alloy liquid metal, and the second part of the heat is finally taken away by the liquid cooling medium; finally, a third part of the heat is lost to the outside through the support frame of the high-thermal-conductivity copper plate; secondly, the heat generated by the battery tab is transferred to the interface phase change material, and finally, the heat is dissipated through convection with air; When the system works in a low-temperature environment, the medium in the microchannel is changed to boiling water, and the heating film on the surface of the interface phase change material preheats the battery, thereby ensuring the temperature consistency of the battery module during the low-temperature preheating process.

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