Aerogel thermal runaway prevention battery assembly

Abstract

The utility model provides an aerogel thermal runaway prevention battery assembly which is suitable for various types of batteries and can be applied to different application scenes. The system comprises an aerogel plate, a battery cell, a phase change material, a liquid cooling plate and an outer frame. According to the invention, by comprehensively using aerogel heat insulation, heat energy storage, phase change materials, cooling fins, liquid cooling and the like, optimal combination of multiple heat management schemes is realized, and the safety and performance stability of a battery system are improved. An aerogel material with heat insulation performance is arranged around the battery and used for preventing heat generated in the battery from being transmitted to surrounding battery cells, and an aerogel plate is of an organic layer-aerogel-organic layer three-layer composite structure and used for improving the adhesion performance of the aerogel plate and a phase change material. In addition, the battery is cooled or preheated by conveying cold water or warm water through the liquid cooling plate, so that the thermal management effect is further improved. The device has the advantages of strong thermal control capability, high safety, good performance stability and compact structure.

Description

Technical Field

[0001] The utility model relates to the technical field of thermal management of lithium ion batteries, in particular to an aerogel thermal runaway-proof battery assembly. Background Art

[0002] As a high-performance, high-energy-density battery, lithium-ion batteries are widely used in electric vehicles, energy storage systems and other fields. In addition to electric vehicles and energy storage systems, batteries are increasingly used as energy storage devices in the construction field. In the construction field, batteries are mainly used to store renewable energy such as solar energy and wind energy to balance the energy demand of the power supply system and the difference between energy peaks and valleys. However, due to long-term use and high-power discharge, a large amount of heat will be generated inside the battery, causing the battery temperature to rise. Excessive battery temperature will not only shorten the battery life, but may also cause thermal runaway, and even lead to serious safety accidents such as battery explosion and fire. In order to solve the problem of battery thermal management, various methods have been proposed, such as using heat dissipation technologies such as liquid cooling plates and heat pipes, and thermal energy storage technologies such as phase change materials. However, most of the current battery thermal management solutions are single liquid cooling, air cooling or phase change cooling. There are many problems with a single thermal management system, such as liquid cooling has high heat dissipation efficiency but will cause a huge temperature difference in the battery, affecting battery consistency; air cooling has low heat dissipation efficiency and is difficult to meet high-power heat dissipation requirements; phase change cooling has a good temperature equalization effect but is often flammable.

[0003] Therefore, a battery assembly that combines multiple thermal management solutions is urgently needed. Among these problems, the flammability of phase change materials and the problem of battery heat diffusion are particularly important. In order to solve the above problems, aerogel, as a material with excellent thermal insulation and vibration buffering properties, has considerable flame retardancy. It can effectively isolate the heat generated inside the battery and prevent the heat from spreading to other battery packs.

[0004] In the prior art, for example, the publication number CN 207690971 U is a membrane structure for heat insulation between battery cells and a battery pack thereof. The heat insulation film is composed of two pieces of packaging cloth sandwiching aerogel, and the adjacent battery cells are separated by the heat insulation film to prevent heat diffusion in the case of thermal runaway of the battery. However, due to the low thermal conductivity of aerogel, this method cannot solve the heat dissipation problem of the battery, but will aggravate the heat accumulation of the battery cell, which is not conducive to the safe operation of the battery cell. The utility model aims to provide a battery pack thermal management system that suppresses the propagation of thermal runaway through aerogel to solve the problem of thermal runaway diffusion in the prior art. By arranging a heat-insulating aerogel material around the battery, the heat generated inside the battery can be effectively prevented from being transferred to the surrounding environment. At the same time, by adding heat dissipation fins to the outer frame around the battery, the heat dissipation capacity of the outer frame to the phase change material is improved, and a more efficient temperature uniformity and heat dissipation effect can be achieved. In addition, the battery can be cooled or preheated by delivering cold water or warm water through a liquid cooling plate to further improve the thermal management effect. Utility Model Content

[0005] In order to solve the above technical problems, the purpose of the utility model is to fill the problems existing in the current single battery thermal management method and the problem of thermal runaway, and propose an aerogel thermal runaway-proof battery component to ensure the safe operation of the battery thermal management component.

[0006] In order to solve the above problems and achieve the above purposes, the technical solution of the utility model is: an aerogel battery assembly that prevents thermal runaway. This assembly mainly includes an aerogel plate, a battery cell, a phase change material, a liquid cooling plate, and an outer frame. The aerogel plate is used to separate the battery cell and the phase change material to reduce the effects of thermal energy conduction and heat diffusion; the phase change material is used to fill around the battery cell to improve the heat dissipation performance of the battery cell; the liquid cooling plate is placed at the bottom of the battery to further enhance the heat dissipation effect of the battery cell. The outer frame is connected to the phase change material and is used to fix the battery pack and dissipate heat from the phase change material.

[0007] The aerogel plate is a three-layer composite structure of "organic layer-aerogel-organic layer", in which the aerogel is located in the middle layer, which is a carbon dioxide aerogel or boron nitride aerogel, with low thermal conductivity and good flame retardant properties, which can effectively reduce the transfer of heat between battery cells and prevent heat from diffusing to other battery cells. The organic layer is an organic layer with similar properties to the phase change material, ensuring good compatibility and adhesion with the phase change material. The organic layer can be added by a solution method, a gas phase method, or a physical deposition method. The substances contained in the organic layer include but are not limited to the following types: polymer films, such as polyethylene, polypropylene, polystyrene, etc., or polymer blended films, such as polyvinyl alcohol / polyacrylate blended films or polymer composite films, such as polyvinyl alcohol / polyacrylate composite films or copolymer films, such as polymethyl methacrylate-ethyl methacrylate copolymer films.

[0008] The phase change material is prepared by melt blending paraffin and polymer, wherein the polymer is a mixture of one or more of olefin block copolymers or polyethylene or polydimethylsiloxane, and is preheated and softened before use to ensure that the phase change material can fit closely with the battery cell to reduce the contact thermal resistance, wherein the phase change material is also added with high thermal conductivity materials such as expanded graphite, Cu powder, graphite and other metal-based or carbon-based materials to ensure that the phase change material has good thermal energy storage characteristics and thermal conductivity, and can quickly absorb and release heat to improve the heat dissipation effect of the battery cell.

[0009] The liquid cooling plate further enhances the heat dissipation effect of the battery cell. By introducing a cooling medium or a heating medium, the battery cell can be quickly cooled or preheated, thereby improving the overall thermal management performance of the battery system. The liquid cooling plate has two working modes. When the battery temperature is too high, the liquid cooling plate delivers 20°C cold water to dissipate heat to the battery cell; when the ambient temperature is too low, the battery is preheated. At this time, the liquid cooling plate delivers 40°C warm water to preheat the battery cell. The cooling medium is a mixed liquid of water, hexane and hexadecane.

[0010] The outer frame has a plurality of arranged heat-conducting fins for improving the heat dissipation capability of the outer frame for the phase change material. The fins are 2 mm thick and 20 mm wide.

[0011] The phase change material can be adjusted according to the specific needs of the battery. By adjusting the type of paraffin and the ratio of paraffin, thermal conductive material and polymer, the phase change material can have appropriate heat storage and heat release capabilities within the operating temperature range; by cooperating with the battery cell and aerogel, the thermal runaway diffusion is effectively reduced to ensure the safety of the battery system, so as to achieve heat storage and heat release within different temperature ranges.

[0012] The phase change material and liquid cooling plate can be designed and customized according to the volume and shape of the battery to ensure optimal thermal management effect.

[0013] The battery thermal management component is applicable to various types of batteries, including lithium-ion batteries, polymer lithium-ion batteries, nickel-metal hydride batteries, etc. The battery thermal management component is applicable to various application scenarios, including home appliances, electric vehicles, energy storage systems, mobile devices, etc., to improve the safety and performance stability of the battery system.

[0014] The utility model provides an aerogel thermal runaway-proof battery assembly to solve the thermal runaway diffusion problem existing in the prior art. The system has the following advantages:

[0015] 1. Efficient thermal insulation: Aerogel has excellent thermal insulation properties and can effectively prevent the heat generated inside the battery from being transferred to the surrounding environment. By placing thermally insulating aerogel materials around the battery, the spread of thermal runaway can be effectively suppressed and the safety of the battery can be improved.

[0016] 2. Good vibration buffering performance: Aerogel and phase change materials have good vibration buffering performance, which can play a buffering role when the battery is subjected to external impact or vibration, reduce the impact on the battery, and increase the battery life.

[0017] 3. Considerable flame retardancy: BN aerogel or SiO2 aerogel has high flame retardancy, which can effectively reduce the risk of fire caused by thermal runaway and improve the safety of batteries.

[0018] 4. Improved heat dissipation effect: By adding heat dissipation fins to the outer frame around the battery pack, the heat dissipation capacity of the outer frame to the phase change material can be increased, further improving the heat dissipation effect and temperature equalization effect. This can slow down the temperature rise of the battery cell and extend the service life of the battery cell.

[0019] 5. Multiple thermal management solutions complement each other: The system can combine the liquid cooling plate to deliver cold or warm water with aerogel to cool or preheat the battery cells. This allows for flexible thermal management according to actual needs and improves the overall thermal management effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 Schematic diagram of battery thermal management components to prevent thermal runaway using aerogel.

[0022] Figure 2 Top view of battery thermal management components that use aerogel to prevent thermal runaway.

[0023] Figure 3 For the outer frame.

[0024] Figure 4 Aerogel board.

[0025] In the figure: 1. phase change material, 2. battery cell, 3. aerogel plate, 4. liquid cooling plate, 5. outer frame, 6. outer frame wall, 7. fins, 8. organic layer, 9. aerogel. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the present utility model, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the utility model product is usually placed when used. It is only for the convenience of describing the utility model and simplifying the 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 therefore cannot be understood as a limitation on the present utility model.

[0029] In addition, the terms “first”, “second”, “third”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0030] In addition, the terms "horizontal", "vertical", "overhanging", etc. do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connection", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific implementations.

[0034] The aerogel thermal runaway-proof battery thermal management component mainly includes: an aerogel plate 3, a battery cell 2, a phase change material 1, a liquid cooling plate 4, and an outer frame 5. The aerogel plate 3 is used to separate the battery cell 2 and the phase change material to reduce the effects of heat conduction and heat diffusion; the phase change material 1 is used to fill around the battery cell 2 to improve the heat dissipation performance of the battery cell 2; the liquid cooling plate 4 is placed at the bottom of the battery cell 2 to further enhance the heat dissipation effect of the battery cell 2. The outer frame 5 is connected to the phase change material 1 and is used to fix the battery cell group and dissipate heat from the phase change material 1.

[0035] The aerogel plate 3 is a three-layer composite structure of "organic layer-aerogel-organic layer", in which the aerogel is located in the middle layer, which is a carbon dioxide aerogel or boron nitride aerogel, has low thermal conductivity and good flame retardant properties, can effectively reduce the heat transfer between the battery cells 2, and prevent the heat from diffusing to other battery cells 2. The organic layer is an organic material with similar properties to the phase change material 1, ensuring good compatibility and adhesion with the phase change material 1. The organic layer can be added by a solution method, a gas phase method, or a physical deposition method. The substances contained in the organic layer include but are not limited to the following types: polymer films, such as polyethylene, polypropylene, polystyrene, etc., or polymer blended films, such as polyvinyl alcohol / polyacrylate blended films or polymer composite films, such as polyvinyl alcohol / polyacrylate composite films or copolymer films, such as polymethyl methacrylate-ethyl methacrylate copolymer films.

[0036] The phase change material 1 is prepared by melt blending of paraffin and polymer, wherein the polymer is a mixture of one or more of olefin block copolymers or polyethylene or polydimethylsiloxane. It is preheated and softened before use to ensure that the phase change material 1 can fit closely with the battery cell 2 to reduce the contact thermal resistance. The phase change material 1 is also added with high thermal conductivity materials such as expanded graphite, Cu powder, graphite and other metal-based or carbon-based materials to ensure that the phase change material 1 has good thermal energy storage characteristics and thermal conductivity, and can quickly absorb and release heat to improve the heat dissipation effect of the battery cell 2.

[0037] The outer frame 5 has a plurality of arranged heat-conducting fins 7 for improving the heat dissipation capability of the outer frame 5 for the phase change material 1. The fins 7 are 2 mm thick and 20 mm wide.

[0038] The phase change material 1 can be adjusted according to the specific needs of the battery cell 2. By adjusting the type of paraffin and the ratio of paraffin, thermal conductive material and polymer, the phase change material 1 can have appropriate heat storage and heat release capabilities within the operating temperature range; by cooperating with the battery cell 2 and aerogel, the thermal runaway diffusion is effectively reduced to ensure the safety of the battery system, so as to achieve heat storage and heat release within different temperature ranges.

[0039] The phase change material 1 and the liquid cooling plate 4 can be designed and customized according to the volume and shape of the battery cell 2 to ensure the best thermal management effect.

[0040] Battery thermal management components are suitable for various types of batteries, including lithium-ion batteries, polymer lithium-ion batteries, nickel-metal hydride batteries, etc. Battery thermal management components are suitable for various application scenarios, including buildings, home appliances, electric vehicles, energy storage systems, mobile devices, etc., to improve the safety and performance stability of battery systems.

[0041] The liquid cooling plate 4 is used to further enhance the heat dissipation effect of the battery cell 2. By introducing a cooling medium or a heating medium, the battery cell 2 can be quickly cooled or preheated, thereby improving the overall thermal management performance of the battery system. The liquid cooling plate 4 has two working modes. When the battery temperature is too high, the liquid cooling plate 4 delivers 20°C cold water to dissipate heat to the battery cell 2; when the ambient temperature is too low, the battery is preheated. At this time, the liquid cooling plate 4 delivers 40°C warm water to preheat the battery cell 2. The cooling medium is a mixed liquid of water, hexane and hexadecane.

[0042] The main implementation process of the fire protection method of this system is as follows:

[0043] 1) Heat dissipation mode: When the battery temperature is too high, the heat dissipation mode of the liquid cooling plate 4 is activated. The phase change material 1 absorbs and stores the heat generated by the battery cell 2. In addition, the cooling medium (a mixed liquid of water, hexane and hexadecane) is transported to the liquid cooling plate 4, thereby forming a flow channel for the cooling medium. The cooling medium flows inside the liquid cooling plate 4, absorbing the heat generated by the battery cell 2 and the heat absorbed by the phase change material 1. After absorbing heat, the cooling medium becomes hotter and takes the heat away. The heat absorbed by the phase change material 1 is also dissipated from the outer frame 5, thereby achieving rapid heat dissipation of the battery cell 2.

[0044] 2) Preheating mode: When the ambient temperature is too low, the liquid cooling plate 4 is started to preheat the battery pack. The heating medium (such as 40°C warm water) is transported to the liquid cooling plate 4, thereby forming a flow channel for the heating medium. During the preheating process, the heating medium continues to flow in the liquid cooling plate 4, transferring heat to the battery cell 2 and the phase change material 1. The phase change material 1 absorbs heat to keep the battery cell 2 warm and preheat it until the battery cell 2 reaches the required operating temperature.

[0045] 3) Prevent thermal runaway: When a battery cell 2 experiences thermal runaway, the aerogel layer can prevent heat from spreading to surrounding components, reducing the impact of heat on other components. At the same time, the aerogel layer can also provide additional insulation performance to prevent heat and current in the battery system from interfering with each other, thereby improving the safety and stability of the battery system.

Claims

1. An aerogel thermal runaway-proof battery assembly, characterized in that: The aerogel thermal runaway-proof battery thermal management component comprises an aerogel plate (3), a battery cell (2), a phase change material (1), a liquid cooling plate (4), and an outer frame (5); The phase change material (1) is used to fill around the battery core (2); The aerogel plate (3) is used to separate the battery core and the phase change material; The liquid cooling plate (4) is placed at the bottom of the battery; The outer frame (5) is connected to the phase change material (1) and is used to fix the battery pack and dissipate heat for the phase change material (1).

2. The aerogel thermal runaway-proof battery assembly according to claim 1, characterized in that: The aerogel plate (3) is a three-layer composite structure of organic layer-aerogel-organic layer, wherein the aerogel is located in the middle layer and is a carbon dioxide aerogel or a boron nitride aerogel; The polymer is an organic material with properties similar to those of the phase change material (1), ensuring good compatibility and adhesion with the phase change material (1).

3. The aerogel thermal runaway-proof battery assembly according to claim 1, characterized in that: The liquid cooling plate (4) further enhances the heat dissipation effect of the battery core (2), and achieves rapid heat dissipation or preheating of the battery core (2) by passing a cooling medium or a heating medium; The liquid cooling plate (4) has two working modes. When the battery temperature is too high, the liquid cooling plate (4) delivers cold water at 20° C. to dissipate heat from the battery cell (2); when the ambient temperature is too low, the battery is preheated. At this time, the liquid cooling plate (4) delivers warm water at 40° C. to preheat the battery cell (2); 4. The aerogel thermal runaway-proof battery assembly according to claim 1, characterized in that: The outer frame (5) has a plurality of arranged heat-conducting fins (7) for improving the heat dissipation capability of the outer frame (5) for the phase change material (1).

5. The aerogel thermal runaway-proof battery assembly according to claim 1, characterized in that: The phase change material (1) can be adjusted according to the specific needs of the battery, so that the phase change material (1) has the ability to store and release heat within the operating temperature range; by cooperating with the battery core (2) and the aerogel.

6. The aerogel thermal runaway-proof battery assembly according to claim 1, characterized in that: The phase change material (1) and the liquid cooling plate (4) are designed and customized according to the volume and shape of the battery.

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