Lightweight temperature-controllable battery thermal management system

Abstract

The utility model discloses a light-weight temperature-controllable battery thermal management system, which comprises batteries, a composite phase-change material, a micro-channel, an interface phase-change material and a heating film, wherein the batteries are connected in series and in parallel to form a battery module; the battery modules are arranged in a staggered manner and are honeycomb-shaped; the composite phase change material wraps the peripheral surface of the battery and is in direct contact with the battery; the micro-channels are longitudinally arranged on the peripheral surface of the composite phase-change material in a layered manner, each micro-channel is in a honeycomb grid shape and surrounds each battery, a water inlet is formed in the edge of one end of each micro-channel, a water outlet is formed in the edge of the other end of each micro-channel, and the vertically adjacent micro-channels are connected through a supporting frame body; the interface phase-change material covers the battery tab, and a heating film is fixed on the other surface of the interface phase-change material; the power battery is simple in structure, meets high safety and convenience of power battery design, highlights lightweight design in the power battery design, reduces system construction cost, has double functions of high-temperature heat dissipation and low-temperature heating, and has wide application space.

Description

Technical Field

[0001] The utility model relates to the technical field of battery thermal management, and in particular to a lightweight temperature-controllable battery thermal management system and an implementation method thereof. Background Art

[0002] As the core component of new energy vehicles, the design and performance of power batteries are very important. When charging and discharging, they will release a lot of heat. If the heat is not discharged in time, it will bring great safety hazards. At the same time, when the ambient temperature is too low, the battery performance will be greatly restricted. For this reason, battery thermal management technology and battery thermal safety have received widespread attention. The goal of thermal management is to control the battery temperature so that the battery can continue to perform at its best in a reasonable temperature range.

[0003] At present, due to the demand for energy emission reduction, electric vehicles need to manufacture medium or large battery modules connected by multiple battery cells to have the smallest possible size and weight, that is, the integration of stacked battery cells in the battery module is required to be continuously improved. For this reason, there is a trend of lightweight battery module design. However, whether it is an air cooling device or a liquid cooling device, there is a great demand for space. For this reason, phase change material cooling technology can make great use of space, thereby minimizing the volume of the battery thermal management module. However, phase change materials have limitations such as weak overall structural strength after phase change and quality risks. It can be seen that a single traditional cooling technology is gradually unable to meet the thermal management needs. In order to achieve the goal of safe, economical and efficient battery thermal management, it is necessary to seek the optimal thermal management system. Therefore, the present application proposes a lightweight controllable temperature battery thermal management system and its implementation method. Utility Model Content

[0004] The purpose of the utility model is to overcome the shortcomings and deficiencies of the prior art and to provide a lightweight, temperature-controllable battery thermal management system and its implementation method, which couples liquid cooling and phase change material cooling together, takes into account the dual functions of high-temperature heat dissipation and low-temperature heating, and sets composite phase change materials, microchannels, interface phase change materials and heating films to solve the problems raised in the above-mentioned background technology.

[0005] The purpose of the utility model is achieved through the following technical solutions:

[0006] A lightweight temperature-controllable battery thermal management system comprises batteries, which are connected in series and parallel to form a battery module, and also comprises a composite phase change material, a microchannel, an interface phase change material and a heating film; the battery module is arranged in a staggered manner in a honeycomb shape; the composite phase change material is wrapped around the outer peripheral surface of the battery and is in direct contact with it; the microchannels are arranged in layers and longitudinally on the outer peripheral surface of the composite phase change material, the microchannels are in a honeycomb grid shape, surrounding each battery, one end edge of which is provided with a water inlet, the other end edge of which is provided with a water outlet, and the upper and lower adjacent microchannels are connected by a supporting frame; the interface phase change material covers the battery tabs, and a heating film is fixed to the other surface of the interface phase change material.

[0007] Furthermore, the honeycomb grid-shaped microchannels connect the single battery heat dissipation modules in series into rows, and each row of battery modules is connected in parallel to form a honeycomb battery thermal management system. The working fluid diffuses rapidly in the microchannels and exchanges heat with the phase change material.

[0008] Furthermore, the microchannel includes a first microchannel and a second microchannel, the first microchannel is horizontally arranged on the outer peripheral surface of the composite phase change material, and there is no communication between layers.

[0009] Furthermore, the second microchannel as a whole is inclined from the water inlet to the water outlet, and the water inlet and the water outlet are connected to the second microchannel of each layer through a connecting pipe. The water inlet is set at the highest point of the second microchannel, and the water outlet is set at the lowest point of the second microchannel.

[0010] Furthermore, the interface phase change material is provided with a through hole, and the through hole is sleeved in the top ear of the battery, so that the interface phase change material is more closely attached to the upper surface of the battery.

[0011] Furthermore, the composite phase change material is a hexagonal hollow column structure, and its outer edge is limited by the honeycomb grid-shaped microchannel and the supporting frame.

[0012] As a preferred solution, the composite phase change material adopts insulating, flame retardant and three-dimensional high thermal conductivity skeleton composite phase change material, specifically metal foam, porous polymer, carbon-based three-dimensional porous material, porous ceramic material.

[0013] As a preferred solution, 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 conductor, a graphene thermal conductive film / gasket, and a carbon fiber thermal conductive gasket.

[0014] As a preferred solution, the support frame is made of a high thermal conductivity metal material, specifically copper.

[0015] As a preferred solution, the heating film material adopts semiconductor materials or components with a large positive temperature coefficient, specifically a resistance wire or a PTC heating film.

[0016] As a preferred solution, the liquid cooling medium in the microchannel during high-temperature heat dissipation is air, liquid water, ethylene glycol and gallium-based alloy liquid metal, and the liquid cooling medium during low-temperature heating is boiling water.

[0017] The utility model also provides a method for implementing a lightweight temperature-controllable battery thermal management system, comprising:

[0018] When the system works in a high temperature environment, a large amount of heat is generated during the battery charging and discharging process, and the temperature of the battery pack continues to rise. 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, the first part of the heat is absorbed by the phase change material and then undergoes a phase change; the second part of the heat is exchanged with the liquid cooling medium in the microchannel, and the liquid cooling medium is air, liquid water, ethylene glycol, and gallium-based alloy liquid metal. The second part of the heat will eventually be carried away by the flow of the liquid cooling medium; the remaining third part of the heat will naturally lose to the outside through the support frame of the high thermal conductivity copper plate; secondly, the heat generated by the battery ear is transferred to the interface phase change material, and finally convectively exchanges heat with the air to dissipate the heat;

[0019] When the system works in a low-temperature environment, the working medium in the microchannel is changed to boiling water; 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.

[0020] Compared with the prior art, the beneficial effects of the utility model are:

[0021] The battery thermal management system of the utility model couples liquid cooling and phase change material cooling together, taking into account the dual functions of high-temperature heat dissipation and low-temperature heating. By setting staggered and honeycomb-shaped battery modules, the composite phase change material is wrapped around the outer peripheral surface of the battery and is in direct contact with it; the microchannels are arranged in layers and longitudinally on the outer peripheral surface of the composite phase change material, and the microchannels are in a honeycomb grid shape, surrounding each battery; the battery module is limited and fixed by the honeycomb grid-shaped microchannels, which is different from the traditional box. It not only has good stability, compact structure and space saving, but also achieves a lightweight effect; it also utilizes the honeycomb type The structure has a fast diffusion path during the working fluid transportation of the microchannel, and the transferred heat is balanced, so the temperature consistency between batteries can be guaranteed regardless of high-temperature heat dissipation or low-temperature heating; the second microchannel is inclined and connecting pipes are arranged between the layers, which accelerates the working fluid transportation speed and improves the overall temperature control effect of the thermal management system; the utility model has a simple structure, meets the high safety and convenience of power battery design, highlights the lightweight design in power battery design, can greatly reduce the cost of system construction, and takes into account the dual functions of high-temperature heat dissipation and low-temperature heating, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is an exploded view of the overall structure of the utility model;

[0023] Figure 2 It is a schematic diagram of the overall structure of the utility model;

[0024] Figure 3 This is the overall structure diagram of the single-layer first microchannel of the utility model;

[0025] Figure 4 This is a schematic diagram of the overall structure of the second embodiment of the present utility model;

[0026] Figure 5 It is a structural schematic diagram of the second microchannel of the utility model;

[0027] Figure 6 It is a schematic diagram of the structure of the composite phase change material of the utility model;

[0028] Figure 7 It is a schematic diagram of the structure of the interface phase change material of the utility model;

[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 pipe. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with embodiments and drawings, but the implementation manner of the present invention is not limited thereto.

[0031] Embodiment 1:

[0032] See also Figure 1-7 , this embodiment provides a technical solution:

[0033] A lightweight temperature-controllable battery thermal management system comprises batteries 1, which are connected in series and parallel to form a battery module, and also comprises a composite phase change material 2, a microchannel, an interface phase change material 5 and a heating film 6; the battery module is arranged in a staggered manner and is in a honeycomb shape; the composite phase change material 2 is wrapped around the outer peripheral surface of the battery 1 and is in direct contact with it; the microchannels are arranged in layers and longitudinally on the outer peripheral surface of the composite phase change material 2, and the microchannels are in a honeycomb grid shape, surrounding each battery 1, wherein a water inlet 7 is provided at one end edge, and a water outlet 8 is provided at the other end edge, and upper and lower adjacent microchannels are connected by a supporting frame 4; the interface phase change material 5 covers the battery 1 pole ear, and a heating film 6 is fixed to the other surface of the interface phase change material 5.

[0034] The battery thermal management system of the present invention couples liquid cooling and phase change material cooling together, taking into account the dual functions of high-temperature heat dissipation and low-temperature heating. By setting a staggered and honeycomb-shaped battery module, the composite phase change material 2 is wrapped around the outer peripheral surface of the battery 1 and is in direct contact with it; the microchannels are layered and arranged longitudinally on the outer peripheral surface of the composite phase change material 2, and the microchannels are in a honeycomb grid shape, surrounding each battery 1; the honeycomb grid-shaped microchannels are used to limit and fix the battery module, which is different from the traditional box. It not only has good stability, compact structure and space saving, but also achieves a lightweight effect; the honeycomb structure is also used, and the diffusion path of the working fluid in the microchannel is fast during the transportation process, and the heat transferred is balanced, so that the temperature consistency between the battery 1 and the battery 1 can be guaranteed whether it is high-temperature heat dissipation or low-temperature heating; the utility model has a simple structure, meets the high safety and convenience of power battery design, highlights the lightweight design in power battery design, can greatly reduce the cost of system construction, and takes into account the dual functions of high-temperature heat dissipation and low-temperature heating, and has a wide range of application space.

[0035] like Figure 1-Figure 3 As shown, in order to further ensure the structural stability of the device, the honeycomb grid-shaped microchannels connect the single battery 1 heat dissipation modules in series into rows, and each row of battery modules is connected in parallel to form a honeycomb battery thermal management system. The working fluid diffuses rapidly in the microchannels and exchanges heat with the phase change material. The thermal management system of this embodiment uses a plurality of single battery 1 hexagonal column heat dissipation modules to form a honeycomb battery thermal management system. The honeycomb structure has good stability, and each unit is independently convenient for disassembly and maintenance, which meets the high safety and convenience of power battery design.

[0036] In this embodiment 1, the microchannel includes a first microchannel 3 and a second microchannel 3-1. Figure 1 and Figure 2 As shown, the first microchannel 3 is used in Example 1, and the first microchannel 3 is horizontally arranged on the outer peripheral surface of the composite phase change material 2, and there is no connection between the layers. The first microchannel 3 is assembled in multiple layers, each layer is provided with a water inlet / outlet 8, and each layer of microchannels can work independently; the first microchannel 3 is a hexagonal pipe, which surrounds each battery 1, exchanges the same heat for each battery 1, and keeps the temperature of the battery module consistent; the hexagonal pipe design structure is compact, the working fluid has many diffusion paths, and the diffusion speed is fast, so that it flows evenly through each single battery 1. Different from the traditional liquid cooling technology, it is not affected by the number of channels, flow velocity and direction, etc., and the occupied space is greatly reduced, achieving the purpose of lightweight thermal management system.

[0037] Embodiment 2:

[0038] like Figure 4 and Figure 5As shown, the structure of this embodiment 2 is basically the same as that of embodiment 1, wherein the microchannels are different. Embodiment 2 adopts a second microchannel 3-1, specifically: the second microchannel 3-1 is tilted as a whole from the water inlet 7 to the water outlet 8, and the water inlet 7 and the water outlet 8 are connected to the second microchannel 3-1 of each layer through a connecting pipe 9, the water inlet 7 is arranged at the highest point of the second microchannel 3-1, and the water outlet 8 is arranged at the lowest point of the second microchannel 3-1; considering the flow rate and flow direction of the working fluid transport, the second microchannel 3-1 is tilted compared to the first microchannel 3, so as to avoid backflow of the working fluid and further accelerate the diffusion speed of the working fluid.

[0039] The same parts of Examples 1 and 2 are further described below:

[0040] like Figure 4 As shown, the interface phase change material 5 is provided with a through hole 5-1, and the through hole 5-1 is sleeved in the top ear of the battery 1, so that the interface phase change material 5 is more closely attached to the upper surface of the battery 1; the purpose of setting the through hole 5-1 is: 1. to make the interface phase change material 5 more closely attached; 2. to make the heating film 6 in direct contact with the battery 1.

[0041] like Figure 6 As shown, the composite phase change material 2 is a hexagonal hollow column structure, and its outer edge is limited by the honeycomb grid-shaped microchannel and the support frame 4. The composite phase change material 2 of this embodiment fully surrounds and contacts the battery 1, further enhancing the heat conduction effect.

[0042] In order to improve the heat dissipation efficiency of the single cell 1, the composite phase change material 2 adopts insulating, flame retardant and three-dimensional high thermal conductivity skeleton composite phase change material, specifically metal foam, porous polymer, carbon-based three-dimensional porous material, porous ceramic material, including: metal foam (foam copper, foam aluminum, foam 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 foam nickel and paraffin composite phase change material, porous SiC ceramic / paraffin composite phase change material, etc.

[0043] In order to improve the heat dissipation efficiency at the battery 1 tab, the interface phase change material 5 adopts a high thermal conductivity phase change interface material, specifically an indium-based alloy thermal conductive gasket, a liquid metal thermal conductor, a graphene thermal conductive film / gasket, and a carbon fiber thermal conductive gasket.

[0044] In order 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 microchannel in this embodiment is also made of a high thermal conductivity metal such as copper, which has good compressive resistance and enables the battery 1 to have high stability and good mechanical strength.

[0045] In the present embodiment, the heating film 6 is made of semiconductor materials or components with a large positive temperature coefficient, specifically a resistance wire or a PTC heating film; the heating film 6 of the present embodiment is composed of a single-layer resistance wire, a square shell, and a wire. The heating resistance wire is arranged through the center of each battery cell. The resistance wire is relatively thin and is assembled inside the square shell and is conductively conducted by the wire.

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

[0047] On the basis of the above technical solution, this embodiment further proposes a method for implementing a lightweight temperature-controllable battery thermal management system, including:

[0048] When the system works in a high temperature environment, a large amount of heat is generated during the charging and discharging process of the battery 1, and the temperature of the battery pack continues to rise. 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, the first part of the heat is absorbed by the phase change material and then undergoes a phase change; the second part of the heat exchanges heat with the liquid cooling medium in the microchannel, and the liquid cooling medium is air, liquid water, ethylene glycol, and gallium-based alloy liquid metal. The second part of the heat will eventually be carried away by the flow of the liquid cooling medium; the remaining third part of the heat will naturally lose to the outside through the support frame 4 of the high thermal conductivity copper plate; secondly, the heat generated by the battery 1 pole ear is transferred to the interface phase change material 5, and finally convects with the air to dissipate the 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, thereby ensuring the temperature consistency of the battery module during the low temperature preheating process.

[0050] The above is a preferred implementation mode of the present invention, but the implementation mode of the present invention is not limited by the above content. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principle of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A lightweight temperature-controllable battery thermal management system, comprising batteries, wherein the batteries are connected in series and parallel to form a battery module, characterized in that: It also includes a composite phase change material, a microchannel, an interface phase change material and a heating film; the battery modules are staggered and arranged in a honeycomb shape; the composite phase change material is wrapped around the outer peripheral surface of the battery and is in direct contact with it; the microchannels are layered and arranged longitudinally on the outer peripheral surface of the composite phase change material, and the microchannels are in a honeycomb grid shape, surrounding each battery, wherein a water inlet is provided at one end edge, and a water outlet is provided at the other end edge, and the upper and lower adjacent microchannels are connected by a supporting frame; the interface phase change material covers the battery ears, and a heating film is fixed on the other surface of the interface phase change material.

2. The battery thermal management system according to claim 1, characterized in that: The honeycomb grid-shaped microchannels connect the single battery heat dissipation modules in series into rows, and each row of battery modules is connected in parallel to form a honeycomb battery thermal management system. The working fluid diffuses rapidly in the microchannels and exchanges heat with the phase change material.

3. The battery thermal management system according to claim 1, characterized in that: The microchannel comprises a first microchannel and a second microchannel. The first microchannel is horizontally arranged on the outer peripheral surface of the composite phase change material, and there is no communication between layers.

4. The battery thermal management system according to claim 3, characterized in that: The second microchannel is tilted from the water inlet to the water outlet as a whole. The water inlet and the water outlet are connected to the second microchannel of each layer through connecting pipes. The water inlet is set at the highest point of the second microchannel, and the water outlet is set at the lowest point of the second microchannel.

5. The battery thermal management system according to claim 1, characterized in that: The interface phase change material is provided with a through hole, and the through hole is sleeved in the top ear of the battery, so that the interface phase change material is more closely attached to the upper surface of the battery.

6. The battery thermal management system according to claim 1, characterized in that: The composite phase change material is a hexagonal hollow column structure, and the outer edge of the composite phase change material is limited by the honeycomb grid-shaped microchannel and the support frame.

7. The battery thermal management system according to claim 1, characterized in that: 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 conductor, a graphene thermal conductive film / gasket, and a carbon fiber thermal conductive gasket.

8. The battery thermal management system according to claim 1, characterized in that: The support frame is made of a high thermal conductivity metal material, specifically copper.

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