Sealed type heat dissipation composite condensation glue

Abstract

The invention belongs to the technical field of new energy storage batteries, and provides a sealed heat dissipation composite condensation adhesive. The composite condensing gel sequentially comprises an aluminum-plastic film, condensing gel, a glass fiber mesh, an aluminum-plastic film, mica paper, aerogel, mica paper, an aluminum-plastic film, a glass fiber mesh, condensing gel and an aluminum-plastic film from top to bottom. The composite condensing gel provided by the invention can utilize the characteristic that 92% of the composite condensing gel contains condensate to quickly release heat of a battery cell when a battery is quickly charged and discharged, so that the performance of the battery is improved, and the service life of the battery is prolonged. Once the battery has a thermal runaway phenomenon, the heat dissipation condensation gel can absorb a large amount of heat through phase change, so that the progress of thermal runaway is slowed down.

Description

Technical Field

[0001] The invention relates to the technical field of new energy storage batteries, and in particular to a sealed heat dissipation composite cold gel. Background Art

[0002] In the production and application of new energy batteries, efficient thermal management technology is one of the core challenges to ensure battery performance and safety. Batteries generate a lot of heat during the charging and discharging process. If the heat is not dissipated in time, the temperature inside the battery cell will continue to rise, which may cause diaphragm failure, short circuit or even thermal runaway accidents. In addition, the problem of battery capacity attenuation and reduced endurance in low temperature environments also requires a balance between heat preservation and heat dissipation. Although traditional heat dissipation solutions such as liquid cooling systems can partially alleviate the problem, their complex structure, reliance on fluid circulation and the risk of leakage make it difficult to meet the compactness and reliability requirements of high energy density batteries. The traditional battery separator material uses aerogel. The advantages of aerogel are mainly strong thermal insulation and light weight, but aerogel cannot solve the problem of battery heat dissipation and slow down the process of thermal runaway. Therefore, how to provide a gel composite material with the ability to dissipate heat and slow down thermal runaway has become an urgent problem in this field. Summary of the invention

[0003] In view of this, the present invention provides a sealed heat dissipation composite cold gel, the purpose of which is to solve the problems of insufficient heat dissipation capacity and easy thermal runaway during rapid charging and discharging of the battery.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The invention provides a sealed heat dissipation composite cold gel, which comprises, from top to bottom, aluminum-plastic film, cold gel, glass fiber mesh, aluminum-plastic film, mica paper, aerogel, mica paper, aluminum-plastic film, glass fiber mesh, cold gel and aluminum-plastic film.

[0005] Furthermore, the thickness of the aerogel is 0.5-1.5 mm.

[0006] Furthermore, the thickness of the mica paper is 0.05-0.2 mm.

[0007] Furthermore, the thickness of the aluminum-plastic film is 0.08-0.12 mm.

[0008] Furthermore, the thickness of the glass fiber mesh is 0.18-0.42 mm.

[0009] Furthermore, the thickness of the cold gel is 0.4-5 mm.

[0010] It can be seen from the above technical solution that compared with the prior art, the beneficial effects of the present invention are as follows: The sealed heat dissipation composite cold gel provided by the present invention imitates the heat dissipation of human body sweating. The composite cold gel is placed in the laminated battery cell. Through the evaporation of the cold gel water, the heat of the power battery is quickly dissipated to achieve the temperature control effect.

[0011] The sealed heat-dissipating composite cold gel provided by the present invention has a strong heat dissipation capacity. It utilizes the 92% water solid content and the high enthalpy value of water to store and absorb heat. When the battery is fast charged or discharged, it can effectively release the heat generated by each battery cell, which not only improves the performance of the new energy battery and extends the service life, but also avoids the problem of the electrode layer falling off due to heat.

[0012] The sealed heat dissipation composite cold gel provided by the present invention has strong heat insulation ability and strong flexibility, and can cover a large area of ​​the battery cell surface, quickly absorbing and dissipating the heat of the battery cell evenly; and because the cold gel material in the composite cold gel absorbs heat and evaporates, the internal thermal conductivity is poor, so it can effectively prevent heat from being transferred between the two battery cells.

[0013] The sealed heat dissipation composite cold gel provided by the present invention has the ability to protect against thermal runaway. When the temperature of the battery core is too high, water evaporates quickly to cool it and control the temperature, thereby preventing the thermal runaway phenomenon from further deteriorating. Even if the battery core burns, the composite cold gel contains a layer of thermal insulation material mainly composed of aerogel, which can delay the transmission of thermal runaway. When the temperature of the battery core further increases, the three-dimensional water storage structure of the composite cold gel is destroyed, and a large amount of water vapor will burst out to isolate the air and extinguish the open fire. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a structural diagram of the sealed heat dissipation composite cryogel provided by the present invention, wherein 1 is aerogel, 2 is mica paper, 3 is aluminum-plastic film, 4 is glass fiber mesh, 5 is cryogel, and 6 is aluminum-plastic film; Figure 2 A physical picture of the sealed heat dissipating composite cryogels provided by the present invention, wherein Figure A is a cross-sectional view of the composite cryogels, and Figure B is a half cross-sectional view of the composite cryogels; Figure 3 Cold / hot surface diagram for thermal insulation testing; Figure 4 This is the result of the thermal shock test; Figure 5 This is the pressure test result diagram; Figure 6 This is the hardness curve at different temperatures for freezing point test. DETAILED DESCRIPTION

[0015] The invention provides a sealed heat dissipation composite cold gel, which comprises, from top to bottom, aluminum-plastic film, cold gel, glass fiber mesh, aluminum-plastic film, mica paper, aerogel, mica paper, aluminum-plastic film, glass fiber mesh, cold gel and aluminum-plastic film.

[0016] In the present invention, the thickness of the aerogel is 0.5-1.5 mm, preferably 1.0 mm.

[0017] In the present invention, the thickness of the mica paper is 0.05-0.2 mm, preferably 0.1 mm.

[0018] In the present invention, the thickness of the aluminum-plastic film is 0.08-0.12 mm, preferably 0.1 mm.

[0019] In the present invention, the thickness of the glass fiber mesh is 0.18-0.42 mm, preferably 0.2-0.4 mm, and more preferably 0.3 mm.

[0020] In the present invention, the mesh size of the glass fiber mesh is preferably 12×14 mm.

[0021] In the present invention, the thickness of the cryogel is 0.4-5 mm, preferably 0.5 mm.

[0022] In the present invention, the cold gel used is from Chinese Patent Publication No. CN117126430B or Chinese Patent Publication No. CN117363238B.

[0023] In the present invention, the working principle of the composite cryogel is as follows: ① Normal working stage -20~85℃, this stage is the normal working state of the battery. In this stage, the composite cold gel mainly absorbs the heat of the battery through the specific heat capacity (sensible heat) of the condensate, thereby slowing down the rate of temperature rise of the battery, increasing the time the battery can work at a suitable temperature, and further improving the performance, endurance and service life of the battery; ② Thermal runaway stage 85~200℃, in this stage, the battery temperature gradually rises abnormally due to various reasons, but no open flame has been generated. In this stage, the composite cold gel mainly relies on the process of phase transformation of the gel condensate into gaseous state to absorb a large amount of heat (latent heat) of the equipment and slow down the development of thermal runaway; ③ Thermal runaway stage above 200℃, in this stage, the battery begins to have open flames. Once an open flame appears, the thermal runaway of the battery will be more severe, and the heat generation rate will exceed the heat absorption rate of the composite cold gel. Once the open flame spreads to other battery packs, the thermal runaway will be aggravated. At this stage, the composite cold gel mainly relies on the internal aerogel and phase-changing water vapor (water vapor has good thermal insulation properties) to combine and insulate the battery fire in the battery pack, thereby slowing down the spread of thermal runaway. In general, on the basis of providing a strong heat dissipation capacity for the battery, an "airbag" is also installed for the battery pack to better protect the life safety of passengers.

[0024] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0025] Example 1 A sealed heat dissipation composite cold gel, which comprises, from top to bottom, aluminum-plastic film, cold gel, glass fiber mesh, aluminum-plastic film, mica paper, aerogel, mica paper, aluminum-plastic film, glass fiber mesh, cold gel and aluminum-plastic film. The thickness of the aerogel is 1.0 mm, the thickness of the mica paper is 0.1 mm, the thickness of the aluminum-plastic film is 0.1 mm, the thickness of the glass fiber mesh is 0.3 mm, the mesh size of the glass fiber mesh is 12×14 mm, the thickness of the cold gel is 0.5 mm, and the cold gel is prepared according to patent CN117363238B.

[0026] The preparation process is as follows: first cut mica paper and aerogel, stack them according to the hierarchical structure, then wrap them with aluminum-plastic film and vacuum seal them to obtain an intermediate product, use a yarn filling machine to fix the glass fiber mesh and the aluminum-plastic film on both sides of the intermediate product respectively, use a gel filling machine to fill the cold gel and vacuum seal it, and use a shaping machine to beautify it to obtain a sealed heat dissipation composite cold gel.

[0027] Example 2 A sealed heat dissipation composite cold gel, which comprises, from top to bottom, aluminum-plastic film, cold gel, glass fiber mesh, aluminum-plastic film, mica paper, aerogel, mica paper, aluminum-plastic film, glass fiber mesh, cold gel and aluminum-plastic film. The thickness of the aerogel is 1.2 mm, the thickness of the mica paper is 0.12 mm, the thickness of the aluminum-plastic film is 0.09 mm, the thickness of the glass fiber mesh is 0.4 mm, the mesh size of the glass fiber mesh is 12×14 mm, the thickness of the cold gel is 0.5 mm, and the cold gel is prepared according to patent CN117363238B, and the preparation process is the same as that of Example 1.

[0028] Example 3 A sealed heat dissipation composite cold gel, which comprises, from top to bottom, aluminum-plastic film, cold gel, glass fiber mesh, aluminum-plastic film, mica paper, aerogel, mica paper, aluminum-plastic film, glass fiber mesh, cold gel and aluminum-plastic film. The thickness of the aerogel is 0.9 mm, the thickness of the mica paper is 0.08 mm, the thickness of the aluminum-plastic film is 0.11 mm, the thickness of the glass fiber mesh is 0.2 mm, the mesh size of the glass fiber mesh is 12×14 mm, the thickness of the cold gel is 0.5 mm, and the cold gel is prepared according to patent CN117126430B, and the preparation process is the same as that of Example 1.

[0029] Example 4 A sealed heat dissipation composite cold gel, which comprises, from top to bottom, aluminum-plastic film, cold gel, glass fiber net, aluminum-plastic film, mica paper, aerogel, mica paper, aluminum-plastic film, glass fiber net, cold gel and aluminum-plastic film. The thickness of the aerogel is 1.1 mm, the thickness of the mica paper is 0.09 mm, the thickness of the aluminum-plastic film is 0.1 mm, the thickness of the glass fiber net is 0.2 mm, the mesh size of the glass fiber net is 12×14 mm, the thickness of the cold gel is 0.5 mm, and the cold gel is prepared according to patent CN117126430B, and the preparation process is the same as that of Example 1.

[0030] Performance Testing 1.800℃ insulation test: Set the temperature of the heating platform to 800℃ and start heating. When it reaches 800℃, press with 1N pressure for 10min to detect the temperature of the cold surface. The test results are shown in Table 1 and Figure 3 .

[0031] Table 1 Thermal insulation test results

[0032] As shown in Table 1, the composite cryogel provided by the present invention has stable performance. Figure 3 It can be seen that the composite cold gel provided by the present invention has a strong heat insulation ability.

[0033] 2. Salt spray test conditions: The mass concentration of the sodium chloride solution is 5%, the air pressure is 1.00±0.01MPa, the test chamber temperature is 47℃, the temperature of the salt water barrel is 35℃, the spray volume is 26mL, and the test conditions and results are described in Table 2.

[0034] Table 2 Salt spray test results

[0035] 3. A product with a larger mass was prepared by the method of Example 1, and a thermal shock test was performed. The test contents were as follows: thermal shock test chamber, low temperature -40°C / 0.5h, transfer to high temperature 85°C / 0.5h within 30min, this as one cycle, repeat the cycle 1000 times, then 1h high temperature, 1h low temperature, 3min interval in between, do 375 cycles, take out and let stand for 2h after the end, the test results are shown in Table 3 and Figure 4 .

[0036] Table 3 Thermal shock test results

[0037] 4. Pressure test: Use ZQ-990A pressure testing machine, test speed is 50mm / min, sample area is 2500mm 2 , the gauge length is 20.00mm. The test results are shown in Figure 5 ,Depend on Figure 5 It can be obtained that the maximum pressure is 432.29N and the deformation at the maximum force point is 3.16mm.

[0038] 5. Aging resistance test: A new composite cold gel was prepared using Example 1 and aged for 1400 h at a temperature of 85 ° C and a relative humidity of 20% RH. The weight was measured every 200 hours, and then the static gel was taken out. After 2 h, the test results are shown in Table 4. After the sample was cut open, the gel was intact, but there was water loss, with a water loss of 5.9%.

[0039] Table 4 Aging test results

[0040] 6. Freezing point test: A composite cryogel with a size of 130×85×3 mm was prepared using Example 1. The freezing point test was performed at an average temperature of 20°C in the test room. The composite cryogel was placed in a constant temperature and humidity chamber, and the humidity was adjusted to a minimum of 20%. The temperatures were adjusted to 0°C, -1°C, -2°C, -3°C, -4°C, -5°C, -6°C, -7°C, -8°C, -9°C and -10°C, respectively. Each temperature setting time was 5 hours. The machine was stopped, taken out, cut open, and the hardness was tested with a hardness tester to observe the freezing and icing conditions. The test results are shown in Figure 6 After being taken out from a constant temperature and humidity chamber at -7℃ for 5 hours, the gel felt stiff. The aluminum foil packaging film was cut open and the gel turned white. The hardness value of the hardness tester increased significantly, indicating that the freezing point of the composite cold gel was -7℃.

[0041] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A sealed heat dissipation composite cold gel, characterized in that: From top to bottom, they include aluminum-plastic film, cold gel, glass fiber mesh, aluminum-plastic film, mica paper, aerogel, mica paper, aluminum-plastic film, glass fiber mesh, cold gel and aluminum-plastic film.

2. The sealed heat dissipation composite cold gel according to claim 1, characterized in that: The thickness of the aerogel is 0.5-1.5 mm.

3. The sealed heat dissipation composite cold gel according to claim 2, characterized in that: The thickness of the mica paper is 0.05-0.2 mm.

4. A sealed heat dissipation composite cold gel according to any one of claims 1 to 3, characterized in that: The thickness of the aluminum-plastic film is 0.08-0.12 mm.

5. The sealed heat dissipation composite cold gel according to claim 4, characterized in that: The thickness of the glass fiber mesh is 0.18-0.42 mm.

6. A sealed heat dissipating composite cold gel according to claim 2, 3 or 5, characterized in that: The thickness of the cold gel is 0.4-5 mm.

Images