A mica composite component for a CCS lithium battery core conductive plate and its preparation method

Abstract

The present application relates to the technical field of CCS lithium battery components, in particular to a mica composite component for a CCS lithium battery cell conductive plate and a preparation method thereof. A mica composite component for a CCS lithium battery cell conductive plate comprises a mica composite substrate, an electronic-grade glass cloth compounded inside the mica composite substrate, and a copper foil compounded on the surface of the mica composite substrate. The mica composite substrate comprises the following raw materials in parts by weight: 80-90 parts of a surface-modified mica composition, 0.5-5 parts of a toughening filler, and 20-32 parts of a compounded silicone resin; the toughening filler is composed of nano-aramid fiber combined with at least one of nano-carbon fiber, carbon nanotube, and inorganic whisker. The present application is used to manufacture a signal acquisition component for a CCS lithium battery, which can effectively improve the thermal runaway safety performance of a CCS lithium battery module, and has the advantages of low dielectric loss, high reliability, and high insulation and thermal conductivity, contributing to the high-quality development of the new energy vehicle industry.

Description

Technical Field

[0001] The present application relates to the technical field of CCS lithium battery components, and in particular to a mica composite component for a conductive plate of a CCS lithium battery cell and a preparation method thereof. Background Art

[0002] The lithium battery module CCS is an electrical connection structural component within the lithium battery module. It is installed in the lithium battery module by integrating information acquisition components, plastic structural components, aluminum bars and other components into an electronic control module to achieve functions such as high-voltage series and parallel connection of battery cells, battery temperature sampling, battery cell voltage sampling, and overcurrent fusing. It is part of the BMS battery management system.

[0003] Currently, mature design solutions for CCS signal acquisition components include wiring harnesses, PCBs, FPCs, and FFCs. The signal acquisition components industrially applied to new energy battery pack modules are mainly PCB boards. Compared with wiring harnesses, PCB boards as signal acquisition components have more advantages in product integration, lightweight, and regular structure. They are conducive to better utilization of the internal space of the battery, facilitate automated assembly, and are suitable for large-scale mass production.

[0004] As the core component for energy storage and output, the power battery pack of a new energy vehicle (NEV) determines its driving comfort, endurance stability, and thermal runaway safety. Thermal runaway safety of the power battery pack determines the safety and personal protection of vehicle users in the event of a battery module failure, and is currently a hotly debated issue for consumers. Improving the thermal runaway safety of NEV power battery packs is a key R&D breakthrough for every automaker.

[0005] The PCB board traditionally used in the signal acquisition component of CCS lithium batteries is made by impregnating electronic-grade glass cloth with epoxy resin adhesive and baking it to form a semi-cured sheet. Several semi-cured sheets are stacked together to form a substrate, and then one or both sides are covered with copper foil to obtain a semi-finished product. The semi-finished product is then hot-pressed, solidified, and cut to obtain a finished PCB board. Finally, an integrated circuit is formed based on the finished PCB board.

[0006] However, the flame retardant safety performance of the finished PCB board formed by the existing epoxy resin adhesive + electronic-grade glass cloth is average. The signal acquisition component of the CCS lithium battery is assembled on the upper end of the electrode of the lithium battery cell. When the lithium battery cell explodes due to an abnormal accident, the flame generated by the explosion and the high temperature of the finished PCB board are the first to be affected. The flame retardant performance of the finished PCB board under high temperature and high heat is relatively average. In fact, the epoxy resin adhesive can produce toxic and combustion-supporting gases at high temperature, which can no longer meet the thermal runaway safety performance requirements of the power battery pack of new energy vehicles. To this end, the inventors provide a mica composite component for the conductive plate of the CCS lithium battery cell and its preparation method. Summary of the Invention

[0007] In order to solve the problem that the flame retardancy of the above-mentioned prior art is relatively general, and even the epoxy resin adhesive can no longer meet the thermal runaway safety performance requirements of the power battery pack of new energy vehicles due to the generation of toxic and combustion-supporting gases at high temperatures, the inventors provide a mica composite component for the conductive plate of a CCS lithium battery cell and a preparation method thereof.

[0008] The present application provides a mica composite component for a conductive plate of a CCS lithium battery cell, which is realized by the following scheme:

[0009] A mica composite component for a conductive plate of a CCS lithium battery cell comprises a mica composite substrate, at least one electronic-grade glass cloth composited to the interior of the mica composite substrate, and copper foil composited to the surface of the mica composite substrate. The mica composite substrate is made of the following raw materials in parts by weight: 80-90 parts of a surface-modified mica composition, 0.5-5 parts of a toughening filler, and 20-32 parts of a compounded silicone resin with a solid content of 40-55wt%. The surface-modified mica composition comprises a mica matrix and nanoscale modified particles supported on the surface of the mica matrix, the nanoscale modified particles comprising at least one of aluminum oxide, silicon dioxide, titanium dioxide, aluminum nitride, silicon nitride, graphene, carbon nanotubes, and fullerenes. The toughening filler is composed of nano-aramid fibers combined with at least one of nano-carbon fibers, carbon nanotubes, and inorganic whiskers.

[0010] Preferably, the mica matrix is ​​1340 mesh sieve material, D 10 0.5-2μm, D 50 3-5.5μm, D 90 7.5-9.5μm.

[0011] The mica composite component for the conductive plate of the CCS lithium battery cell in this application is used to manufacture the signal acquisition component of the CCS lithium battery, which can effectively improve the thermal runaway safety performance of the CCS lithium battery module, and has the advantages of low dielectric loss, high reliability, and high insulation and thermal conductivity, which is conducive to the high-quality development of the new energy vehicle industry.

[0012] Preferably, the nano-scale modified particles are aluminum oxide and carbon nanotubes, the aluminum oxide is loaded and fixed on the surface of the mica substrate by a sol-gel method; the carbon nanotubes are fixed on the surface of the mica substrate by sintering with nano-silver or nano-copper.

[0013] By adopting the above technical solution, the overall high insulation thermal conductivity of the mica composite parts can be improved while ensuring thermal runaway safety performance, low dielectric loss and high reliability, and heat can be effectively released, which can better meet the use requirements of power battery packs.

[0014] Preferably, the toughening filler is composed of nano-aramid fiber and inorganic whiskers in a mass ratio of (3-7):1; the inorganic whiskers are at least one of zinc oxide whiskers, aluminum nitride whiskers, aluminum oxide whiskers, boron nitride whiskers, and silicon carbide whiskers.

[0015] By adopting the above technical solution, the overall impact toughness can be effectively improved, which is not only beneficial to improving the overall processing performance and mechanical strength, but also to improving the overall high insulation and thermal conductivity, which can better meet the use requirements of power battery packs.

[0016] Preferably, the mica composite substrate is made of the following raw materials in parts by weight: 81.4-83.2 parts of a surface-modified mica composition, 2.8-3.6 parts of a toughening filler, and 28-30 parts of a compounded silicone resin with a solid content of 50 wt%.

[0017] By optimizing the design of the mica composite substrate formula, the overall thermal runaway safety performance, low dielectric loss, high reliability, and high insulation thermal conductivity can be improved while reducing the overall production cost. It is also convenient to improve the quality stability of products in the same batch.

[0018] Preferably, the preparation method of the surface-modified mica composition is as follows:

[0019] Step 1: loading and fixing nano-scale modified particles A on the surface of a mica substrate by a sol-gel method, wherein the nano-scale modified particles A are at least one of aluminum oxide, silicon dioxide, titanium dioxide, aluminum nitride, and silicon nitride;

[0020] Step 2: Add polyvinyl pyrrolidone and nano-scale modified particles B to the prepared Ag(2E4MI)2Ac complex solution, wherein the nano-scale modified particles AB are at least one of graphene, carbon nanotubes, and fullerene. After ultrasonic dispersion for 1-4 hours, add the mica matrix material with the surface-loaded nano-scale modified particles A in step 1, and then ultrasonically disperse for 0.5-2 hours;

[0021] Step 3: The dispersion obtained in step 2 is subjected to reduced pressure distillation to remove the organic solvent in the Ag(2E4MI)2Ac complex solution, and the obtained solid is subjected to high-temperature sintering treatment for 2-4 hours at a high-temperature sintering temperature of 200-220°C;

[0022] Step 4: Roll-grinding and crushing the solid obtained in step 3, wet-milling the obtained powder at a ball mill speed of 60-80 rpm for 15-40 minutes, and then filtering, drying, and sieving to obtain a semi-finished surface-modified mica composition;

[0023] Step 5: Place the semi-finished surface-modified mica composition obtained in step 4 in an aminosilane aqueous solution for ultrasonic dispersion treatment for 30-90 minutes, wherein the concentration of aminosilane in the aminosilane aqueous solution is 0.5-6wt%, and the aminosilane includes at least one of KH550, KH540, KH554, and KH590, filter, and dry to obtain a finished surface-modified mica composition.

[0024] By adopting the above technical solution, a finished surface-modified mica composition with good compatibility and bonding with the compounded silicone resin can be obtained, thereby improving the overall thermal runaway safety performance, low dielectric loss, high reliability, and high insulation thermal conductivity.

[0025] Preferably, the compounded silicone resin with a solid content of 40-55wt% is made from the following raw materials in parts by weight: 200 parts of KR-242A silicone resin, 50-100 parts of KR-271 silicone resin, 20-40 parts of a toughening composition with a molecular weight ≥1000, 20-60 parts of xylene, 20-60 parts of isopropanol, 0.20-0.30 parts of diethylenetriamine, and 0.10-0.20 parts of 1H-benzimidazole-1,5,6-triamine; the toughening composition is at least one of end-side chain epoxy silicone oil chain extender IOTA105-3, double-end alcohol hydroxy silicone oil IOTA 2110, double-end alcohol hydroxy long-chain alkyl silicone oil IOTA-8865H, hydroxyl-terminated methyl vinyl silicone oil IOTA 1203V, carbon hydroxy silicone oil IOTA 2122, and carbon hydroxy silicone oil IOTA 2140.

[0026] Preferably, the preparation method of the compounded silicone resin with a solid content of 40-55wt% is as follows: 0.05-0.10 parts of diethylenetriamine, 200 parts of KR-242A silicone resin, 50-100 parts of KR-271 silicone resin, and 20-40 parts of a toughening composition with a molecular weight ≥1000 are pre-reacted at 68-70°C for 100-200s, cooled to 0-4°C in an ice-water bath, 40-60 parts of xylene and 20-60 parts of isopropanol are added, and stirred at 80-160rpm for 10-30min, the remaining diethylenetriamine and 0.10-0.20 parts of 1H-benzimidazole-1,5,6-triamine are added, and stirred at 60-80rpm for 100-200s to obtain the silicone resin, which is then stored at low temperature for standby use.

[0027] By adopting the above technical solution, the overall structure can be given good flame retardancy, fire safety, high temperature resistance and impact toughness.

[0028] The present application provides a method for preparing a mica composite component for a CCS lithium battery cell conductive plate, which is achieved through the following technical solutions:

[0029] A method for preparing a mica composite component for a CCS lithium battery cell conductive plate comprises the following steps:

[0030] Step 1: preparing a surface-modified mica composition and a compounded silicone resin with a solid content of 40-55 wt % respectively;

[0031] Step 2: The surface-modified mica composition, the toughening filler, and the compounded silicone resin with a solid content of 40-55wt% in step 1, which are accurately measured, are evenly mixed to obtain a mica composite substrate slurry. The obtained mica composite substrate slurry is poured into a forming mold, and after heating to remove the organic solvent, a four-step hot pressing method is used to prepare a semi-finished mica composite substrate. The obtained semi-finished mica composite substrate is heated to 50-55°C at a heating rate of 1-2°C / min and kept warm for 200-300s, and then heated to 80-88°C at a heating rate of 1-2°C / min and kept warm for 60-120min, and naturally cooled to obtain a finished mica composite substrate;

[0032] At the same time, the surface of the copper foil is subjected to low-temperature plasma treatment, and ammonia treatment is used for 5-30 minutes at 0-4°C. The surface of the copper foil after the low-temperature plasma treatment is coated with 0.5-1g / dm2 of the compounded silicone resin with a solid content of 40-55wt% in step 1. 2 After the organic solvent is removed by heating, an organic silica gel film is formed on the surface of the copper foil after low-temperature plasma treatment;

[0033] Step three: stack an electronic-grade glass cloth between adjacent finished mica composite substrates and preheat and press to form a mica substrate, and cover the surface of the mica substrate with the copper foil stacked in step two. The organic silicone film on the surface of the copper foil is in contact with the surface of the mica substrate, and finally perform hot pressing and curing. The mica composite component for the conductive plate of the CCS lithium battery cell can be obtained by hot pressing at a pressure of 2-4 MPa and a temperature of 160-240°C for 2-4 minutes and naturally cooling to room temperature.

[0034] Preferably, the four-step hot pressing molding method in step 2 is as follows: the hot pressing conditions in the first step of hot pressing molding are a platen temperature of 80±2°C, a pressure of 0.25±0.05Mpa, and a duration of 60-80s; the hot pressing conditions in the second step of hot pressing molding are a platen temperature of 130-135°C, a pressure of 0.5-0.6Mpa, and a duration of 100-120s; the hot pressing conditions in the third step of hot pressing molding are a platen temperature of 175-180°C, a pressure of 0.8-1.0Mpa, and a duration of 120-160s; the hot pressing conditions in the fourth step of hot pressing molding are a platen temperature of 115-120°C, a pressure of 0.4-0.6Mpa, and a duration of 60-80s, to obtain a semi-finished mica composite substrate.

[0035] The preparation method provided in this application is relatively simple, has low implementation difficulty, and is easy to implement for industrial mass production.

[0036] In summary, this application has the following advantages:

[0037] 1. This application is used to manufacture signal acquisition components for CCS lithium batteries, which can effectively improve the thermal runaway safety performance of CCS lithium battery modules, and has the advantages of low dielectric loss, high reliability, and high insulation and thermal conductivity, which is conducive to the high-quality development of the new energy vehicle industry.

[0038] 2. This application optimizes the design of the mica composite substrate formula, and the glue content is preferably controlled at 14-15w%, which not only improves the overall thermal runaway safety performance, low dielectric loss, high reliability, and high insulation thermal conductivity, but also reduces the overall production cost and facilitates improving the quality stability of products in the same batch.

[0039] 3. The finished surface-modified mica composition obtained by surface-modifying the mica composition in this application has good compatibility and bonding with the compounded silicone resin. The mica composite parts for the conductive plates of CCS lithium battery cells prepared using the mica composite parts have good thermal runaway safety performance, low dielectric loss, high reliability, and high insulation and thermal conductivity.

[0040] 4. The preparation method provided in this application is relatively simple, has low implementation difficulty, and is easy to implement for industrial mass production. DETAILED DESCRIPTION

[0041] In order to further understand the present invention, preferred embodiments of the present invention are described below with reference to examples and comparative examples.

[0042] Preparation Example 1: The preparation method of the surface-modified mica composition is as follows:

[0043] Step 1: rutile nano-TiO2 is loaded and fixed on the surface of the mica matrix by the sol-gel method. The specific preparation method is as follows: 5g of 1340-mesh sifted phlogopite powder (325-mesh phlogopite is crushed by ball milling and sieved with a 1340-mesh sieve, and the sieved material is the 1340-mesh sifted phlogopite powder), 14.5g of titanium oxysulfate and 49.1g of deionized water are mixed and stirred for about 4h until clear and transparent, and then 1.7g of polyvinyl pyrrolidone (average molecular weight of 54,000) is added and stirred for 5h until clear and transparent, and then 1 7.3g of glycerol and 17.3g of dimethylformamide were stirred for 10min, and then allowed to stand for 24h to obtain titanium dioxide / phlogopite binary colloid. The binary colloid was then washed three times with distilled water, and the solid powder was filtered and dried in a vacuum drying oven at 125°C for 12h. The solid powder was then calcined in a transposed atmosphere tube furnace. The temperature was raised to 980°C at 20°C / min in an air atmosphere and calcined for 3h. The product was ball milled at 60rpm for 30min and then sieved through a 1340 mesh sieve to obtain rutile nano-TiO2 / phlogopite. 10 1.38μm, D 50 3.87μm, D 90 8.31μm;

[0044] Meanwhile, prepare Ag(2E4MI)2Ac complex solution: add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc into 400 mL of dichloromethane at room temperature, and stir magnetically at a speed of 240 r / min until the AgAc particles completely disappear to obtain Ag(2E4MI)2Ac complex solution;

[0045] Step 2: Add 0.3 g of polyvinyl pyrrolidone and 0.2 g of carbon nanotubes (CNTs, TNGM2, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences) to the prepared Ag(2E4MI)2Ac complex solution, ultrasonically disperse for 2 h at an ultrasonic frequency of 40 kHz / 800 W, then add 5 g of rutile nano-TiO2 / phlogopite prepared in step 1, and ultrasonically disperse for 1 h at an ultrasonic frequency of 40 kHz / 800 W to obtain a finished dispersion;

[0046] Step 3: The finished dispersion obtained in step 2 is subjected to reduced pressure distillation to remove dichloromethane, and then the obtained solid is transferred to a muffle furnace and heated to 210° C. for high-temperature sintering for 3 hours to obtain a solid;

[0047] Step 4: The solid obtained in step 3 is placed in a three-roll mill (the roller spacing of the three-roll mill is 10 μm) and ground three times. The resulting powder is transferred to a planetary ball mill and wet-milled (ethanol to powder solid-liquid ratio of 1:3) at a ball mill speed of 60-80 rpm for 30 minutes. After filtering and drying, it is sieved with 1340 mesh to obtain a semi-finished surface-modified mica composition;

[0048] Step 5: Place 5 g of the semi-finished surface-modified mica composition obtained in step 4 in 200 mL of KH540 aqueous solution (KH540 concentration 2 wt%) and ultrasonically disperse for 60 min at an ultrasonic frequency of 40 kHz / 800 W, filter, and dry to obtain a finished surface-modified mica composition.

[0049] The difference between Preparation Example 2 and Preparation Example 1 is that: Step 1, ZnO is loaded and fixed on the surface of the mica substrate by the sol-gel method. The specific preparation method is as follows: 12.6g of zinc acetate is dissolved in 1L of distilled water and magnetically stirred for 0.5h, 40g of 1340 mesh sifted phlogopite powder and 0.25g of polyethylene glycol PEG-400 are added, and magnetic stirring is continued for 0.5h, and then 3wt% concentration of ammonia water is added until Zn is completely precipitated and magnetic stirring is continued for 1h, and the mixture is allowed to stand for 1 hour. ZnOH / phlogopite binary colloid was obtained by chemical treatment for 24 hours. The obtained binary colloid was washed three times with distilled water and filtered to obtain solid powder. The solid powder was transferred to a vacuum drying oven and dried at 125°C for 12 hours. The solid powder was then transferred to an atmosphere tube furnace for calcination. The solid powder was heated to 720°C at a speed of 20°C / min in an air atmosphere and calcined for 3 hours to obtain ZnO / phlogopite powder. The solid powder was wet-milled at 60 rpm for 30 minutes and then sieved through a 1340 mesh sieve to obtain nano ZnO / phlogopite. 10 1.24μm, D 50 3.76μm, D 90 It is 8.09μm.

[0050] The difference between Preparation Example 3 and Preparation Example 1 is that: Step 1, Al2O3 is loaded and fixed on the surface of the mica substrate by the sol-gel method. The specific preparation method is as follows: 18g of aluminum nitrate nonahydrate is dissolved in 1L of distilled water and magnetically stirred for 0.5h, and then 40g of 1340 mesh sifted phlogopite powder is added, and magnetic stirring is continued for 0.5h, and then a 3wt% concentration of sodium hydroxide aqueous solution is added until Al is completely precipitated and magnetic stirring is continued for 1h, and the product is obtained by standing and aging for 24h. Al(OH)3 / phlogopite binary colloid was washed three times with distilled water and then filtered to obtain solid powder, which was then placed in a vacuum drying oven and dried at 125°C for 12 hours. The solid powder was then placed in an atmosphere tube furnace for calcination. The solid powder was heated to 600°C at a rate of 20°C / min in an air atmosphere and calcined for 4 hours to obtain Al2O3 / phlogopite powder. The solid powder was wet-milled at 60 rpm for 30 minutes and then sieved through a 1340 mesh sieve to obtain nano-Al2O3 / phlogopite. 10 1.43 μm, D 50 3.94μm, D 90 It is 8.39μm.

[0051] Preparation Example 4 differs from Preparation Example 1 in that: Step 1, AlN is loaded and fixed on the surface of the mica substrate by a sol-gel method. The specific preparation method is as follows: 0.1 mol of aluminum nitrate nonahydrate and 0.3 mol of glucose are dissolved in 1 L of distilled water and magnetically stirred for 0.5 h, and then 40 g of 1340 mesh sifted phlogopite powder and 0.25 g of polyethylene glycol PEG-400 are added. After being placed in a constant temperature water bath at 75°C, 5 g of urea is added and a 3 wt% concentration of ammonia solution is added dropwise while stirring to obtain an alumina sol. The temperature is then increased to evaporate most of the water to obtain a gel, which is then freeze-dried to form AlN. The precursor / phlogopite powder is placed in a sealed vacuum carbon tube furnace, and the temperature is increased while vacuuming to gradually remove water and carbonize the organic matter in the precursor in the absence of oxygen, and form a uniformly mixed and loose porous material with the aluminum oxide generated by the decomposition of aluminum hydroxide. By controlling the nitrogen flow rate and continuously increasing the temperature, it is finally nitrided at 1550℃ for 3h to obtain carbon-containing AlN, which is placed in a decarburization furnace and decarburized at 800℃ / 2h under a reducing atmosphere of H2 to obtain nano-AlN / phlogopite. After wet ball milling at 60rpm for 30min, it is sieved through a 1340 mesh sieve to obtain nano-scale AlN / phlogopite. 10 1.47μm, D 50 3.82μm, D 90 It is 7.95μm.

[0052] The difference between Preparation Example 5 and Preparation Example 1 is that the preparation method of the surface-modified mica composition is as follows:

[0053] Step 1: rutile nano-TiO2 is loaded and fixed on the surface of the mica substrate by the sol-gel method. The specific preparation method is as follows: 5g of 325-mesh phlogopite powder, 14.5g of titanium sulfate and 49.1g of deionized water are mixed and stirred for about 4h until clear and transparent, then 1.7g of polyvinyl pyrrolidone with an average molecular weight of 54,000 is added and continued to be stirred for 5h until clear and transparent, then 17.3g of glycerol and 17.3g of dimethylformamide are added and stirred for 10min, and then the mixture is stirred for 10min. The titanium dioxide / phlogopite binary colloid was obtained by aging for 24 hours, and then the prepared binary colloid was washed three times with distilled water. The solid powder was filtered and dried in a vacuum drying oven at 125°C for 12 hours, and then calcined in a transposed atmosphere tube furnace. The temperature was increased to 980°C at 20°C / min in an air atmosphere and calcined for 3 hours. The obtained solid was placed on a three-roll mill (the roller spacing of the three-roll mill was 45μm) and ground and pulverized three times to obtain rutile nano-TiO2 / phlogopite.

[0054] Meanwhile, prepare Ag(2E4MI)2Ac complex solution: add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc into 400 mL of dichloromethane at room temperature, and stir magnetically at a speed of 240 r / min until the AgAc particles completely disappear to obtain Ag(2E4MI)2Ac complex solution;

[0055] Step 2: Add 0.3 g of polyvinyl pyrrolidone and 0.2 g of carbon nanotubes CNTs, TNGM2 to the prepared Ag(2E4MI)2Ac complex solution, ultrasonically disperse for 2 h at an ultrasonic frequency of 40 kHz / 800 W, then add 5 g of rutile nano-TiO2 / phlogopite prepared in step 1, and ultrasonically disperse for 1 h at an ultrasonic frequency of 40 kHz / 800 W to obtain a finished dispersion;

[0056] Step 3: The finished dispersion obtained in step 2 is subjected to reduced pressure distillation to remove dichloromethane, and then the obtained solid is transferred to a muffle furnace and heated to 210° C. for high-temperature sintering for 3 hours to obtain a solid;

[0057] Step 4: Place the solid obtained in step 3 on a three-roll mill (the roller spacing of the three-roll mill is 45 μm) and grind it three times to obtain a semi-finished surface-modified mica composition;

[0058] Step 5: Place 5 g of the semi-finished surface-modified mica composition in 200 mL of a 2 wt% KH540 aqueous solution and ultrasonically disperse for 1 hour at an ultrasonic frequency of 40 kHz / 800 W, filter, and dry to obtain a finished surface-modified mica composition. Example

[0059] A mica composite component for a CCS lithium battery core conductive plate comprises a mica composite substrate, at least one electronic-grade glass cloth composited inside the mica composite substrate, and a copper foil composited on the surface of the mica composite substrate.

[0060] The mica composite substrate comprises the following raw materials in parts by weight: 80-90 parts of a surface-modified mica composition, 0.5-5 parts of a toughening filler, and 20-32 parts of a compounded silicone resin with a solid content of 40-55wt%.

[0061] Preferably, the mica composite substrate comprises the following raw materials in parts by weight: 81.4-83.2 parts of a surface-modified mica composition, 2.8-3.6 parts of a toughening filler, and 28-30 parts of a compounded silicone resin with a solid content of 50 wt%.

[0062] The toughening filler is composed of nano-aramid fibers and at least one of nano-carbon fibers, carbon nanotubes, and inorganic whiskers. Preferably, the toughening filler comprises nano-aramid fibers and inorganic whiskers in a mass ratio of (3-7):1. The inorganic whiskers are composed of at least one of zinc oxide whiskers, aluminum nitride whiskers, aluminum oxide whiskers, boron nitride whiskers, and silicon carbide whiskers. Further preferably, the toughening filler comprises nano-aramid fibers and boron nitride whiskers in a mass ratio of 4:1.

[0063] The surface modified mica composition comprises a mica matrix and nano-scale modified particles loaded on the surface of the mica matrix, wherein the mica matrix is ​​a 1340 mesh sieve material, D 10 0.5-2μm, D 50 3-5.5μm, D 90 The nano-scale modified particles include at least one of aluminum oxide, silicon dioxide, titanium dioxide, aluminum nitride, silicon nitride, graphene, carbon nanotubes, and fullerenes. Preferably, the nano-scale modified particles are aluminum oxide and carbon nanotubes, wherein the aluminum oxide is loaded and fixed on the surface of the mica substrate by a sol-gel method, and the carbon nanotubes are fixed on the surface of the mica substrate by sintering nano-silver or nano-copper.

[0064] The preparation method of the surface-modified mica composition is as follows:

[0065] Step 1: loading and fixing nano-scale modified particles A on the surface of a mica substrate by a sol-gel method, wherein the nano-scale modified particles A are at least one of aluminum oxide, silicon dioxide, titanium dioxide, aluminum nitride, and silicon nitride;

[0066] Step 2: Add polyvinyl pyrrolidone and nano-scale modified particles B to the prepared Ag(2E4MI)2Ac complex solution, where the nano-scale modified particles AB are at least one of graphene, carbon nanotubes, and fullerene. After ultrasonic dispersion for 1-4 hours, add the mica matrix material with the surface-loaded nano-scale modified particles A in step 1, and then ultrasonically disperse for 0.5-2 hours.

[0067] Step 3: The dispersion obtained in step 2 is subjected to reduced pressure distillation to remove the organic solvent in the Ag(2E4MI)2Ac complex solution, and the obtained solid is subjected to high-temperature sintering treatment for 2-4 hours at a high-temperature sintering temperature of 200-220°C;

[0068] Step 4: Roll-grinding and crushing the solid obtained in step 3, wet-milling the obtained powder at a ball mill speed of 60-80 rpm for 15-40 minutes, and then filtering, drying, and sieving to obtain a semi-finished surface-modified mica composition;

[0069] Step 5: Place the semi-finished surface-modified mica composition obtained in step 4 in an aminosilane aqueous solution for ultrasonic dispersion treatment for 30-90 minutes, wherein the concentration of aminosilane in the aminosilane aqueous solution is 0.5-6wt%, and the aminosilane includes at least one of KH550, KH540, KH554, and KH590, filter, and dry to obtain a finished surface-modified mica composition.

[0070] The compounded silicone resin with a solid content of 40-55wt% in the mica composite substrate formula is made of the following raw materials in parts by weight: 200 parts of KR-242A silicone resin, 50-100 parts of KR-271 silicone resin, 20-40 parts of a toughening composition with a molecular weight ≥1000, 20-60 parts of xylene, 20-60 parts of isopropanol, 0.20-0.30 parts of diethylenetriamine, and 0.10-0.20 parts of 1H-benzimidazole-1,5,6-triamine.

[0071] The toughening composition is at least one of the end-side chain epoxy silicone oil chain extender IOTA 105-3, double-end alcohol hydroxy silicone oil IOTA 2110, double-end alcohol hydroxy long-chain alkyl silicone oil IOTA-8865H, hydroxyl-terminated methyl vinyl silicone oil IOTA 1203V, carbon hydroxy silicone oil IOTA 2122, and carbon hydroxy silicone oil IOTA 2140 of Anhui Aiyota Silicone Oil Co., Ltd.

[0072] The necessity of compounded silicone resin: When using Shin-Etsu's KR-242A silicone resin as the silicone resin to prepare mica composite parts for CCS lithium battery cell conductive plates, it was found during the subsequent machining, stamping and cutting that obvious cracks appeared at the stamping and cutting edges of the mica composite parts for CCS lithium battery cell conductive plates, affecting the overall quality of the mica composite parts for CCS lithium battery cell conductive plates, failing to meet their subsequent processing requirements, and limiting their production and application. The inventors conducted research on the optimized design of compounded silicone resins: a toughening composition and 1H-benzimidazole-1,5,6-triamine curing agent were introduced into the formula to improve the impact toughness of the mica composite parts for CCS lithium battery cell conductive plates while also having good bending strength and insulation and thermal conductivity safety performance, meeting the thermal runaway protection requirements of the signal acquisition components of CCS lithium batteries.

[0073] The preparation method of a compounded silicone resin with a solid content of 40-55 wt% is as follows: 0.05-0.10 parts of diethylenetriamine, 200 parts of KR-242A silicone resin, 50-100 parts of KR-271 silicone resin, and 20-40 parts of a toughening composition with a molecular weight of ≥1000 are pre-reacted at 68-70°C for 100-200 seconds, cooled to 0-4°C in an ice-water bath, and then 40-60 parts of xylene and 20-60 parts of isopropanol are added and stirred at 80-160 rpm for 10-30 minutes, and the remaining diethylenetriamine and 0.10-0.20 parts of 1H-benzimidazole-1,5,6-triamine are added, and stirred at 60-80 rpm for 100-200 seconds to obtain the silicone resin, which is then stored at low temperature for future use.

[0074] A method for preparing a mica composite component for a CCS lithium battery cell conductive plate comprises the following steps:

[0075] Step 1: preparing a surface-modified mica composition and a compounded silicone resin with a solid content of 40-55 wt % respectively;

[0076] Step 2: The surface-modified mica composition, the toughening filler, and the compounded silicone resin with a solid content of 40-55wt% in step 1, which are accurately measured, are evenly mixed to obtain a mica composite substrate slurry. The obtained mica composite substrate slurry is poured into a forming mold, and after heating to remove the organic solvent, a four-step hot pressing method is used to prepare a semi-finished mica composite substrate. The obtained semi-finished mica composite substrate is heated to 50-55°C at a heating rate of 1-2°C / min and kept warm for 200-300s, and then heated to 80-88°C at a heating rate of 1-2°C / min and kept warm for 60-120min, and naturally cooled to obtain a finished mica composite substrate;

[0077] Preferably, the four-step hot pressing molding method is as follows: in the first step of hot pressing molding, the hot pressing conditions are as follows: the pressing plate temperature is 80±2°C, the pressure is 0.25±0.05Mpa, and the duration is 60-80s; in the second step of hot pressing molding, the hot pressing conditions are as follows: the pressing plate temperature is 130-135°C, the pressure is 0.5-0.6Mpa, and the duration is 100-120s; in the third step of hot pressing molding, the hot pressing conditions are as follows: the pressing plate temperature is 175-180°C, the pressure is 0.8-1.0Mpa, and the duration is 120-160s; in the fourth step of hot pressing molding, the hot pressing conditions are as follows: the pressing plate temperature is 115-120°C, the pressure is 0.4-0.6Mpa, and the duration is 60-80s, to obtain a semi-finished mica composite substrate;

[0078] At the same time, a surface of the copper foil is subjected to low-temperature plasma treatment, treated with ammonia gas at 0-4°C for 5-30 minutes, and the surface of the copper foil after the low-temperature plasma treatment is coated with 0.5-1g / dm2 of the compounded organic silicone resin with a solid content of 40-55wt% in step 1, and an organic silicone film is formed on the surface of the copper foil after the low-temperature plasma treatment after heating to remove the organic solvent;

[0079] Step three: stack an electronic-grade glass cloth between adjacent finished mica composite substrates and preheat and press to form a mica substrate, and cover the surface of the mica substrate with the copper foil stacked in step two. The organic silicone film on the surface of the copper foil is in contact with the surface of the mica substrate, and finally perform hot pressing and curing. The mica composite component for the conductive plate of the CCS lithium battery cell can be obtained by hot pressing at a pressure of 2-4 MPa and a temperature of 160-240°C for 2-4 minutes and naturally cooling to room temperature.

[0080] In the preparation method of the above-mentioned mica composite parts for the conductive plates of CCS lithium battery cells, attention should be paid to the design of the forming mold. The forming mold is a simple and low-cost plate-type forming mold, and the final finished mica composite parts for the conductive plates of CCS lithium battery cells are mica composite plates with a thickness of 0.30±0.02mm, which also need to be stamped and cut as the signal acquisition component of the CCS lithium battery. The inventors found in actual processing that the mica and glass fiber will be exposed and protruded at the cut surface of the mica composite plate after stamping and cutting, and the stamping and cutting surface will also be affected by the workpiece clamping friction due to processing requirements, that is, the impurities generated by friction during the processing and assembly process will affect the conductive properties of the lithium battery electrode and will also affect the current circuit etched on the copper foil, affecting the quality of the finally assembled CCS lithium battery cell. To this end, before stamping and cutting the mica composite panels, release films need to be attached to the upper and lower surfaces of the mica composite panels, and then the corresponding stamping and cutting processes are carried out. After the stamping and cutting are completed, the slot section formed is coated with a layer of titanium dioxide wet gel through a gluing process (for preparation by the sol-gel method, see Preparation Example 1), and then placed in a vacuum drying oven to dry at 125°C for 12 hours. The slot section is then laser sintered in an air atmosphere to form a nano-titanium dioxide wear-resistant layer by laser sintering on the slot section, thereby improving the quality of the CCS lithium battery cell.

[0081] Assuming a standardized mica composite component for a CCS lithium battery cell conductive plate, the molding mold is designed with a preset notch, that is, the final finished mica composite substrate is integrally formed with a preset slot. During subsequent processing, the electronic-grade glass fiber mesh needs to be punched to form the corresponding slot to meet the preset slot design of the final CCS lithium battery cell conductive plate mica composite component. There are two options for treating the slot section of the mica composite component for a CCS lithium battery cell conductive plate prepared by this method: the first is to coat the slot section with a layer of titanium dioxide wet gel through the aforementioned gluing process (see Preparation Example 1 for sol-gel method preparation), then dry it in a vacuum drying oven at 125°C for 12 hours, and then laser sinter the slot section in an air atmosphere to form a nano-titanium dioxide wear-resistant layer on the slot section. The second option is to coat the slot section with a compounded silicone resin through the gluing process to form an elastic silicone protective film layer.

[0082] Example 1: A mica composite component for a CCS lithium battery cell conductive plate comprises a mica composite substrate, an electronic-grade glass cloth laminated within the mica composite substrate, and copper foil laminated to the surface of the mica composite substrate. The mica composite substrate is made from 82 parts of the surface-modified mica composition described in Preparation Example 1, 3 parts of a toughening filler, and 30 parts of a compounded silicone resin with a solid content of 50 wt%. The toughening filler is composed of nano-aramid fibers and boron nitride whiskers in a mass ratio of 4:1.

[0083] Preparation method of nano-aramid fiber: Aramid nanofiber dispersion U51 is prepared by a proton donor-assisted deprotonation method. Specifically, 2 g of para-aramid (DuPont Teijin para-aramid chopped PPTA, equivalent diameter 1 μm, length 1 mm) fiber is weighed and placed in a mixed solution of 3 g KOH, 1 L DMSO and 40 mL deionized water. The solution is stirred in a water bath at 60°C for 3 h to obtain a deep red ANFS dispersion with a mass concentration of 2 g / L. Aramid nanofiber ANFS powder is obtained by nanofiltration. 50 g of aramid nanofiber ANFS powder is ultrasonically dispersed in 1 L isopropanol for use.

[0084] Boron nitride whiskers were from Shanghai Xiangtian Nanomaterials Co., Ltd., XT-BN-X2, with a diameter of 0.5-1 μm and a length of 10-20 μm.

[0085] The compounded silicone resin with a solid content of 50 wt% in the mica composite substrate formula is prepared from 200 g of KR-242A silicone resin, 60 g of KR-271 silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 15 g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H, 20.4 g of xylene, 20 g of isopropyl alcohol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine.

[0086] A method for preparing a mica composite component for a CCS lithium battery cell conductive plate comprises the following steps:

[0087] Step 1: preparing a surface-modified mica composition and a compounded silicone resin with a solid content of 50 wt % respectively;

[0088] The preparation of the surface-modified mica composition is described in Preparation Example 1;

[0089] Preparation method of a composite silicone resin with a solid content of 50 wt%: 0.08 g of diethylenetriamine, 200 g of KR-242A silicone resin, 60 g of KR-271 silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, and 15 g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H are pre-reacted at 70° C. for 180 s, cooled to 0-4° C. in an ice-water bath, and then 20.4 g of xylene and 20 g of isopropanol are added and stirred at 120 rpm for 30 min. 0.12 g of diethylenetriamine and 0.20 g of 1H-benzimidazole-1,5,6-triamine are added, and stirred at 60 rpm for 180 s to obtain a composite silicone resin with a solid content of 50 wt%;

[0090] Step 2: Evenly mix 720 g of the surface-modified mica composition accurately measured in step 1, 30 g of the toughening filler, and 300 g of the compounded silicone resin with a solid content of 50 wt% in step 1 to obtain a mica composite substrate slurry. The obtained mica composite substrate slurry is poured into a molding mold, and after heating to remove the organic solvent (xylene and isopropyl alcohol), a four-step hot pressing method is used to prepare a semi-finished mica composite substrate. The four-step hot pressing method is as follows: in the first step of hot pressing, the hot pressing conditions are as follows: the pressing plate temperature is 80 ° C, the pressure is 0.25 MPa, and the duration is 60 s; in the second step of hot pressing, the hot pressing conditions are as follows: the pressing plate temperature is 135 ° C, the pressure is 0.6Mpa, duration is 120s, the hot pressing conditions in the third step of hot pressing molding are a platen temperature of 180°C, a pressure of 1Mpa, and a duration of 150s; the hot pressing conditions in the fourth step of hot pressing molding are a platen temperature of 120°C, a pressure of 0.6Mpa, and a duration of 80s, and naturally cooled to room temperature to obtain a semi-finished mica composite substrate, the obtained semi-finished mica composite substrate is heated to 50°C at a heating rate of 1°C / min and kept warm for 300s, and then heated to 85°C at a heating rate of 2°C / min and kept warm for 100min, and naturally cooled to obtain a finished mica composite substrate with a thickness of 0.30±0.02mm;

[0091] At the same time, the surface of the copper foil is subjected to low-temperature plasma treatment, and then treated with ammonia gas at 0°C for 15 minutes. The surface of the copper foil after the low-temperature plasma treatment is coated with 0.6 g / dm2 of the compounded silicone resin with a solid content of 50 wt% in step 1. 2 After heating to remove the organic solvents (xylene and isopropyl alcohol), an organic silica gel film is formed on the surface of the copper foil after completing the low-temperature plasma treatment;

[0092] Step three, take three finished mica composite substrates with a thickness of 0.30±0.02mm, stack an electronic grade glass cloth between adjacent finished mica composite substrates and preheat press to form a mica substrate, the preheat pressing conditions are a pressing plate temperature of 150°C, a pressure of 0.8Mpa, and a duration of 120s; the copper foil in the stacking step 2 is pressed on the surface of the mica substrate formed by preheating, and the organic silicone film on the surface of the copper foil contacts the surface of the mica substrate, and finally hot pressing and curing are performed, hot pressing treatment is carried out at a pressure of 3.2MPa and a temperature of 220°C for 4min, and naturally cooled to room temperature to obtain a mica composite component for the conductive plate of a CCS lithium battery cell.

[0093] The difference between Example 2 and Example 1 is that the mica composite substrate is made of 80 parts of the surface-modified mica composition in Preparation Example 1, 5 parts of toughening filler, and 30 parts of a compounded silicone resin with a solid content of 50 wt%.

[0094] The difference between Example 3 and Example 1 is that the mica composite substrate is made of 89 parts of the surface-modified mica composition in Preparation Example 1, 0.5 parts of a toughening filler, and 21 parts of a compounded silicone resin with a solid content of 50 wt%.

[0095] The difference between Example 4 and Example 1 is that the mica composite substrate is made of 83 parts of the surface-modified mica composition in Preparation Example 1, 3 parts of toughening filler, and 28 parts of a compounded silicone resin with a solid content of 50 wt%.

[0096] The difference between Example 5 and Example 4 is that the mica composite substrate is made of 83 parts of the surface-modified mica composition in Preparation Example 2, 3 parts of toughening filler, and 28 parts of a compounded silicone resin with a solid content of 50 wt%.

[0097] The difference between Example 6 and Example 4 is that the mica composite substrate is made of 83 parts of the surface-modified mica composition in Preparation Example 3, 3 parts of toughening filler, and 28 parts of a compounded silicone resin with a solid content of 50 wt%.

[0098] The difference between Example 7 and Example 4 is that the mica composite substrate is made of 83 parts of the surface-modified mica composition in Preparation Example 4, 3 parts of toughening filler, and 28 parts of a compounded silicone resin with a solid content of 50 wt%.

[0099] The difference between Example 8 and Example 4 is that the surface-modified mica composition in Preparation Example 1 is replaced by a 1340-mesh sieve-discharged material - rutile nano-TiO2 / phlogopite - obtained by screening with a 1340-mesh sieve.

[0100] The difference between Example 9 and Example 4 is that the surface-modified mica composition in Preparation Example 1 is replaced by a 1340-mesh sieve-discharged material - nano-ZnO / phlogopite - obtained by screening with a 1340-mesh sieve.

[0101] The difference between Example 10 and Example 4 is that the surface-modified mica composition in Preparation Example 1 is replaced by a 1340-mesh sieve-obtained material - nano-Al2O3 / phlogopite - obtained by screening with a 1340-mesh sieve.

[0102] The difference between Example 11 and Example 4 is that the surface-modified mica composition in Preparation Example 1 is replaced by a 1340-mesh sieve-discharged material - nano-sized AlN / phlogopite - obtained by screening with a 1340-mesh sieve.

[0103] The difference between Example 12 and Example 4 is that the toughening filler is composed of nano-aramid fiber and alumina whiskers in a mass ratio of 4:1. The alumina whiskers were purchased from Hubei Xinyuhong Biopharmaceutical Technology Co., Ltd. with specifications of 0.5-1.0 μm in diameter, 10 μm in length, and aspect ratio of 15.

[0104] The difference between Example 13 and Example 4 is that the toughening filler is composed of nano-aramid fiber and boron nitride whiskers in a mass ratio of 2:1.

[0105] The difference between Example 14 and Example 4 is that the toughening filler is composed of nano-aramid fiber and boron nitride whisker in a mass ratio of 7:1.

[0106] The difference between Example 15 and Example 4 is that the toughening filler is composed of nano-aramid fiber and boron nitride whiskers in a mass ratio of 9:1.

[0107] The difference between Example 16 and Example 4 is that the toughening filler is only nano-aramid fiber.

[0108] The difference between Example 17 and Example 4 is that the compound silicone resin with a solid content of 50 wt% in the mica composite substrate formula is prepared from 200 g of KR-242A silicone resin, 80 g of KR-271 silicone resin, 10 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 10 g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H, 20.4 g of xylene, 20 g of isopropyl alcohol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine.

[0109] The difference between Example 18 and Example 4 is that the compound silicone resin with a solid content of 50 wt% in the mica composite substrate formula is prepared from 200 g of KR-242A silicone resin, 50 g of KR-271 silicone resin, 20 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 10 g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H, 20.4 g of xylene, 20 g of isopropyl alcohol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine.

[0110] The difference between Example 19 and Example 4 is that the compound silicone resin with a solid content of 50 wt% in the mica composite substrate formula is prepared from 200 g of KR-242A silicone resin, 60 g of KR-271 silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 15 g of hydroxyl-terminated methyl vinyl silicone oil IOTA 1203V, 20.4 g of xylene, 20 g of isopropyl alcohol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine.

[0111] The difference between Example 20 and Example 4 is that the compound silicone resin with a solid content of 50 wt% in the mica composite substrate formula is prepared from 200 g of KR-242A silicone resin, 60 g of KR-271 silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 15 g of carbon hydroxy silicone oil IOTA 2140, 20.4 g of xylene, 20 g of isopropyl alcohol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine.

[0112] Comparative Example 1 differs from Example 1 in that the mica composite substrate is made from 85 parts of the surface-modified mica composition of Preparation Example 1 and 30 parts of a compounded silicone resin having a solids content of 50 wt%. During subsequent machining, stamping, and cutting of the prepared mica composite component for CCS lithium battery cell conductive plates, fine cracks were observed on the mica substrate at the edges of the stamping process, affecting the overall quality of the component.

[0113] Comparative Example 2 differs from Example 1 in that the mica composite substrate is made from 82 parts of a conventional surface-modified mica composition, 3 parts of a toughening filler, and 30 parts of a compounded silicone resin with a solid content of 50 wt%. The conventional surface-modified mica composition was prepared as follows: 5 g of phlogopite powder sieved through a 1340-mesh sieve was placed in 200 mL of a 2 wt% aqueous solution of KH540 and ultrasonically dispersed at 40 kHz / 800 W for 60 minutes. The mixture was then filtered and dried.

[0114] The difference between Comparative Example 3 and Example 1 is that the mica composite substrate is made of 82 parts of the surface-modified mica composition in Preparation Example 5, 3 parts of toughening filler, and 30 parts of a compounded silicone resin with a solid content of 50 wt%.

[0115] The difference between Comparative Example 4 and Example 1 is that the mica composite substrate is made of 79 parts of the surface-modified mica composition in Preparation Example 1, 3 parts of toughening filler, and 36 parts of a compounded silicone resin with a solid content of 50 wt%.

[0116] Comparative Example 5 differs from Example 1 in that the mica composite substrate is made from 88 parts of the surface-modified mica composition of Preparation Example 1, 3 parts of a toughening filler, and 18 parts of a compounded silicone resin having a solid content of 50 wt%. During subsequent machining, stamping, and cutting of the prepared mica composite component for CCS lithium battery cell conductive plates, fine cracks were observed on the mica substrate at the edges of the stamping and cutting process, affecting the overall quality of the component.

[0117] Comparative Example 6 differs from Example 1 in that a compounded silicone resin with a solid content of 50 wt% was prepared from 340 g of KR-242A silicone resin and 0.25 g of diethylenetriamine. During subsequent machining, stamping, and cutting of the prepared mica composite component for CCS lithium battery cell conductive plates, significant cracks were observed in the mica substrate at the edges of the stamping process, affecting the overall quality of the component.

[0118] Comparative Example 7 differs from Example 1 in that a composite silicone resin with a solid content of 50 wt% was prepared from 260 g of KR-242A silicone resin, 80 g of KR-271 silicone resin, and 0.25 g of diethylenetriamine. During subsequent machining, stamping, and cutting of the prepared mica composite component for CCS lithium battery cell conductive plates, fine cracks were observed in the mica substrate at the edges of the stamping process, affecting the overall quality of the component.

[0119] Comparative Example 8 differs from Example 1 in that KR-271 silicone resin is not added to the 50 wt% solid content composite silicone resin formula. The 50 wt% solid content composite silicone resin formula is prepared from 260 g of KR-242A silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 15 g of double-terminal hydroxyl long-chain alkyl silicone oil IOTA-8865H, 20.4 g of xylene, 20 g of isopropyl alcohol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine.

[0120] The difference between Comparative Example 9 and Example 1 is that the compound silicone resin with a solid content of 50 wt% in the mica composite substrate formula is prepared from 260 g of KR-271 silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 15 g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H, 20.4 g of xylene, 20 g of isopropanol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine.

[0121] The difference between Comparative Example 10 and Example 1 is that: in step 2, 720g of the surface-modified mica composition in step 1, 30g of the toughening filler, and 300g of the compounded silicone resin with a solid content of 50wt% in step 1 are mixed evenly to obtain a mica composite substrate slurry, and the obtained mica composite substrate slurry is poured into a forming mold, and after heating to remove the organic solvent (xylene and isopropyl alcohol), a two-step hot pressing method is used to prepare a semi-finished mica composite substrate. The four-step hot pressing method is as follows: the first step is hot pressing. The hot pressing conditions during the molding process were a platen temperature of 140°C, a pressure of 0.8 MPa, and a duration of 180 s. The hot pressing conditions during the second step of hot pressing molding were a platen temperature of 180°C, a pressure of 1.2 MPa, and a duration of 240 s. The product was naturally cooled to room temperature to obtain a semi-finished mica composite substrate. The obtained semi-finished mica composite substrate was heated to 85°C at a heating rate of 2°C / min and kept warm for 105 minutes. The product was naturally cooled to obtain a finished mica composite substrate with a thickness of 0.30±0.02 mm.

[0122] The difference between Comparative Example 11 and Example 1 is that: in step 2, the surface of the copper foil is not subjected to low-temperature plasma treatment, and a composite silicone resin with a solid content of 50 wt% is directly added at a temperature of 0.6 g / dm 2 The coating is applied to one surface of the copper foil by knife coating. After heating to remove the organic solvents (xylene and isopropyl alcohol), a copper foil with a surface-composite organic silicone film is obtained. During subsequent machining, stamping, and cutting of the mica composite parts for CCS lithium battery cell conductive plates prepared above, it was discovered that the copper foil warped at the edges of the stamping and cutting process, affecting the overall quality of the mica composite parts for CCS lithium battery cell conductive plates. Therefore, low-temperature plasma treatment of the copper foil surface is necessary during the preparation of these mica composite parts for CCS lithium battery cell conductive plates.

[0123] Performance Testing: 1. Flexural Strength Test: Tested in accordance with GB / T 5019.2-2009, Test Methods for Mica Products, Section 11, "Flexural Strength and Flexural Modulus." Specimen width approximately 25mm, test span 16mm, test speed 50mm / min, indenter radius 5mm. 2. Electrical Strength Test: Tested in accordance with GB / T 5019.2-2009, Test Methods for Mica Products, Section 22, "Electrical Strength." Specimen thickness 0.39mm-0.41mm. Tested using a Φ25mm / Φ75mm cylindrical electrode system, rapid voltage ramp-up (ramp-up rate 1.0kV / s), in 25# transformer oil at 23°C ± 2°C. 3. Thermal Conductivity Test: Tested in accordance with GB / T 10297-1998, "Determination of Thermal Conductivity of Non-Metallic Solid Materials - Hot Wire Method." 4. Dielectric loss factor test method: Measure according to IPC TM-650 2.5.5.5 (50Hz) method.

[0124] Table 1: Test parameters of mica composite products for CCS lithium battery core conductive plates in Examples 1-20 and Comparative Examples 1-10

[0125]

[0126] Combining Examples 1, 4, 12-16 and Comparative Example 1 and Table 1, it can be seen that the nano-aramid fiber combined with the toughening filler composed of inorganic whiskers can improve the overall bending strength, impact toughness, insulation thermal conductivity, and thermal runaway safety performance. At the same time, it can improve the overall processing performance, increase the yield rate of machining, stamping and cutting, and reduce production costs.

[0127] Combining Examples 1-11 and Comparative Examples 2-3 with Table 1, it can be seen that the surface-modified mica composition prepared in this application can improve the overall low dielectric loss, high reliability, high insulation and thermal conductivity, and thermal runaway safety performance.

[0128] Combining Examples 1-3 and Comparative Examples 4-5 with Table 1, it can be seen that when the toughening filler is added in an amount of 3 parts, the glue content in the mica composite substrate is preferably 10-15wt%. Preferably, the glue content in the mica composite substrate is 13.8-14.0wt%.

[0129] Combining Example 4 and Examples 17-20 with Comparative Examples 6-9 and Table 1, it can be seen that the use of the homemade compound silicone resin in this application can ensure the overall bending strength, impact toughness, insulation thermal conductivity, and thermal runaway safety performance, while improving the overall processing performance, improving the yield rate of machining, stamping and cutting, and reducing production costs.

[0130] It can be seen from Example 1 and Comparative Example 9 and Table 1 that the mica composite component for the conductive plate of the CCS lithium battery cell prepared by the preparation method provided in this application has relatively good bending resistance and low dielectric loss.

[0131] To sum up, the mica composite parts for the conductive plates of CCS lithium battery cells in this application are used to make signal acquisition components of CCS lithium batteries, which can effectively improve the thermal runaway safety performance of CCS lithium battery modules, and have the advantages of low dielectric loss, high reliability, and high insulation and thermal conductivity, which is conducive to the high-quality development of the new energy vehicle industry.

Claims

1. A mica composite component for a CCS lithium battery core conductive plate, characterized by: The mica composite substrate comprises a mica composite substrate, at least one electronic-grade glass cloth composited inside the mica composite substrate, and a copper foil composited on the surface of the mica composite substrate. The mica composite substrate is made of the following raw materials in parts by weight: 83 parts of a surface-modified mica composition, 3 parts of a toughening filler, and 28 parts of a compounded silicone resin with a solid content of 50wt%. A composite silicone resin with a solid content of 50 wt% is prepared from 200 g of KR-242A silicone resin, 60 g of KR-271 silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, 15 g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H, 20.4 g of xylene, 20 g of isopropyl alcohol, 0.20 g of diethylenetriamine, and 0.20 g of 1H-benzimidazole-1,5,6-triamine. Preparation method of a composite silicone resin with a solid content of 50 wt% comprising the following steps: pre-reacting 0.08 g of diethylenetriamine, 200 g of KR-242A silicone resin, 60 g of KR-271 silicone resin, 25 g of end-side chain epoxy silicone oil chain extender IOTA 105-3, and 15 g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H at 70° C. for 180 s, cooling the mixture to 0-4° C. in an ice-water bath, adding 20.4 g of xylene and 20 g of isopropyl alcohol, and stirring the mixture at 120 rpm for 30 min; then adding 0.12 g of diethylenetriamine and 0.20 g of 1H-benzimidazole-1,5,6-triamine, and stirring the mixture at 60 rpm for 180 s to obtain a composite silicone resin with a solid content of 50 wt%; The toughening filler is composed of nano-aramid fibers and boron nitride whiskers in a mass ratio of 4:1; The nano-aramid fiber preparation method includes: preparing an aramid nanofiber dispersion U51 by a proton donor-assisted deprotonation method. Specifically, 2 g of para-aramid fiber is placed in a mixed solution of 3 g of KOH, 1 L of DMSO, and 40 mL of deionized water. The para-aramid fiber is para-aramid short-cut PPTA with an equivalent diameter of 1 μm and a length of 1 mm. The solution is stirred in a water bath at 60° C. for 3 h to obtain a deep red ANFS dispersion with a mass concentration of 2 g / L. Aramid nanofiber ANFS powder is obtained by nanofiltration. 50 g of the aramid nanofiber ANFS powder is ultrasonically dispersed in 1 L of isopropyl alcohol for use. The preparation method of the surface-modified mica composition is as follows: Step 1: load and fix rutile nano-TiO2 on the surface of the mica matrix by the sol-gel method. The specific preparation method is as follows: 5g of 1340-mesh sifted phlogopite powder, 14.5g of titanium sulfate and 49.1g of deionized water are mixed and stirred for 4 hours until clear and transparent, and then 1.7g of polyvinyl pyrrolidone with an average molecular weight of 54,000 is added and continued to stir for 5 hours until clear and transparent. The 1340-mesh sifted phlogopite powder is 325-mesh phlogopite. After ball milling, it is sieved with a 1340-mesh sieve, and the sieved material is the obtained 1340-mesh sifted phlogopite. Powder, then add 17.3g of glycerol and 17.3g of dimethylformamide and stir for 10min, let it stand for 24h to obtain titanium dioxide / phlogopite binary colloid, then use distilled water to wash the above binary colloid three times, filter to obtain solid powder, place it in a vacuum drying oven at 125℃ and dry it for 12h, then calcinate it in a transposed atmosphere tube furnace, heat it to 980℃ at 20℃ / min in air atmosphere and calcine it for 3h, ball mill it at 60rpm for 30min and sieve it through 1340 mesh to obtain rutile nano-TiO2 / phlogopite, D 10 1.38μm, D 50 3.87μm, D 90 8.31μm; Meanwhile, prepare Ag(2E4MI)2Ac complex solution: add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc into 400 mL of dichloromethane at room temperature, and stir magnetically at a speed of 240 r / min until the AgAc particles completely disappear to obtain Ag(2E4MI)2Ac complex solution; Step 2: Add 0.3 g of polyvinyl pyrrolidone and 0.2 g of carbon nanotubes to the prepared Ag(2E4MI)2Ac complex solution, ultrasonically disperse for 2 h at an ultrasonic frequency of 40 kHz / 800 W, then add 5 g of rutile nano-TiO2 / phlogopite prepared in step 1, and ultrasonically disperse for 1 h at an ultrasonic frequency of 40 kHz / 800 W to obtain a finished dispersion; Step 3: The finished dispersion obtained in step 2 is subjected to reduced pressure distillation to remove dichloromethane, and then the obtained solid is transferred to a muffle furnace and heated to 210° C. for high-temperature sintering for 3 hours to obtain a solid; Step 4: The solid obtained in step 3 is placed in a three-roll mill for three grindings, the roller spacing of the three-roll mill is 10 μm, and the obtained powder is transferred to a planetary ball mill for wet ball milling at a ball mill speed of 60-80 rpm for 30 min, the solid-liquid ratio of ethanol to powder is 1:3, and the semi-finished surface-modified mica composition is obtained by filtering and drying and sieving with 1340 mesh; Step 5: Place 5 g of the semi-finished surface-modified mica composition obtained in step 4 in 200 mL of a 2 wt% KH540 aqueous solution and ultrasonically disperse for 60 min at an ultrasonic frequency of 40 kHz / 800 W, filter, and dry to obtain a finished surface-modified mica composition.

2. The mica composite component for a CCS lithium battery core conductive plate according to claim 1, characterized in that: The preparation method of the surface-modified mica composition is as follows: Step 1: ZnO is loaded and fixed on the surface of the mica substrate by the sol-gel method. The specific preparation method is as follows: 12.6g of zinc acetate is dissolved in 1L of distilled water and magnetically stirred for 0.5h, then 40g of 1340-mesh sifted phlogopite powder and 0.25g of polyethylene glycol PEG-400 are added, and magnetic stirring is continued for 0.5h, and then 3wt% concentration of ammonia water is added until Zn is completely precipitated and magnetic stirring is continued for 1h, and the mixture is allowed to stand for aging for 24h. ZnOH / phlogopite binary colloid was obtained. The binary colloid was washed three times with distilled water and filtered to obtain solid powder. The solid powder was transferred to a vacuum drying oven and dried at 125°C for 12 hours. The solid powder was then transferred to an atmosphere tube furnace for calcination. The solid powder was heated to 720°C at a speed of 20°C / min in an air atmosphere and calcined for 3 hours to obtain ZnO / phlogopite powder. The solid powder was wet-milled at 60 rpm for 30 minutes and then sieved through a 1340 mesh sieve to obtain nano ZnO / phlogopite. 10 1.24μm, D 50 3.76μm, D 90 8.09μm; Meanwhile, prepare Ag(2E4MI)2Ac complex solution: add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc into 400 mL of dichloromethane at room temperature, and stir magnetically at a speed of 240 r / min until the AgAc particles completely disappear to obtain Ag(2E4MI)2Ac complex solution; Step 2: Add 0.3 g of polyvinyl pyrrolidone and 0.2 g of carbon nanotubes to the prepared Ag(2E4MI)2Ac complex solution, ultrasonically disperse at an ultrasonic frequency of 40 kHz / 800 W for 2 h, then add 5 g of nano-ZnO / phlogopite prepared in step 1, and ultrasonically disperse at an ultrasonic frequency of 40 kHz / 800 W for 1 h to obtain a finished dispersion; Step 3: The finished dispersion obtained in step 2 is subjected to reduced pressure distillation to remove dichloromethane, and then the obtained solid is transferred to a muffle furnace and heated to 210° C. for high-temperature sintering for 3 hours to obtain a solid; Step 4: The solid obtained in step 3 is placed in a three-roll mill for three grindings, the roller spacing of the three-roll mill is 10 μm, and the obtained powder is transferred to a planetary ball mill for wet ball milling at a ball mill speed of 60-80 rpm for 30 min, the solid-liquid ratio of ethanol to powder is 1:3, and the semi-finished surface-modified mica composition is obtained by filtering and drying and sieving with 1340 mesh; Step 5: Place 5 g of the semi-finished surface-modified mica composition obtained in step 4 in 200 mL of a 2 wt% KH540 aqueous solution and ultrasonically disperse for 60 min at an ultrasonic frequency of 40 kHz / 800 W, filter, and dry to obtain a finished surface-modified mica composition.

3. The mica composite component for a CCS lithium battery core conductive plate according to claim 1, characterized in that: The preparation method of the surface-modified mica composition is as follows: Step 1: Al2O3 is loaded and fixed on the surface of the mica matrix by the sol-gel method. The specific preparation method is as follows: 18g of aluminum nitrate nonahydrate is dissolved in 1L of distilled water and magnetically stirred for 0.5h, then 40g of 1340-mesh sifted phlogopite powder is added, and magnetic stirring is continued for 0.5h. Then, a 3wt% concentration of sodium hydroxide aqueous solution is added until Al is completely precipitated and magnetic stirring is continued for 1h. After standing and aging for 24h, Al(OH)3 / phlogopite binary colloid is obtained. The obtained binary colloid is washed three times with distilled water and then filtered to obtain a solid powder. The solid powder is transferred to a vacuum drying oven and dried at 125°C for 12h, and then transferred to an atmosphere tube furnace for calcination. The temperature is increased to 600°C at 20°C / min in an air atmosphere and calcined for 4h to obtain Al2O3 / phlogopite powder. The powder is wet-milled at 60rpm for 30min and then sieved through a 1340-mesh sieve to obtain nano-Al2O3 / phlogopite. 10 1.43 μm, D 50 3.94μm, D 90 8.39μm; Meanwhile, prepare Ag(2E4MI)2Ac complex solution: add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc into 400 mL of dichloromethane at room temperature, and stir magnetically at a speed of 240 r / min until the AgAc particles completely disappear to obtain Ag(2E4MI)2Ac complex solution; Step 2: Add 0.3 g of polyvinyl pyrrolidone and 0.2 g of carbon nanotubes to the prepared Ag(2E4MI)2Ac complex solution, ultrasonically disperse for 2 h at an ultrasonic frequency of 40 kHz / 800 W, then add 5 g of nano-Al2O3 / phlogopite prepared in step 1, and ultrasonically disperse for 1 h at an ultrasonic frequency of 40 kHz / 800 W to obtain a finished dispersion; Step 3: The finished dispersion obtained in step 2 is subjected to reduced pressure distillation to remove dichloromethane, and then the obtained solid is transferred to a muffle furnace and heated to 210° C. for high-temperature sintering for 3 hours to obtain a solid; Step 4: The solid obtained in step 3 is placed in a three-roll mill for three grindings, the roller spacing of the three-roll mill is 10 μm, and the obtained powder is transferred to a planetary ball mill for wet ball milling at a ball mill speed of 60-80 rpm for 30 min, the solid-liquid ratio of ethanol to powder is 1:3, and the semi-finished surface-modified mica composition is obtained by filtering and drying and sieving with 1340 mesh; Step 5: Place 5 g of the semi-finished surface-modified mica composition obtained in step 4 in 200 mL of a 2 wt% KH540 aqueous solution and ultrasonically disperse for 60 min at an ultrasonic frequency of 40 kHz / 800 W, filter, and dry to obtain a finished surface-modified mica composition.

4. The mica composite component for a CCS lithium battery core conductive plate according to claim 1, characterized in that: The preparation method of the surface-modified mica composition is as follows: Step 1: AlN is loaded and fixed on the surface of the mica substrate by the sol-gel method. The specific preparation method is as follows: 0.1 mol of aluminum nitrate nonahydrate and 0.3 mol of glucose are dissolved in 1 L of distilled water and magnetically stirred for 0.5 h, then 40 g of 1340 mesh sifted phlogopite powder and 0.25 g of polyethylene glycol PEG-400 are added, and the mixture is placed in a constant temperature water bath at 75 ° C, 5 g of urea is added, and a 3 wt% concentration of ammonia solution is added dropwise while stirring to obtain an alumina sol. The temperature is then increased to evaporate most of the water to obtain a gel, which is then freeze-dried to form AlN. The precursor / phlogopite powder is placed in a sealed vacuum carbon tube furnace, and the temperature is increased while vacuuming to gradually remove water and carbonize the organic matter in the precursor in the absence of oxygen, and form a uniformly mixed and loose porous material with the aluminum oxide generated by the decomposition of aluminum hydroxide. By controlling the nitrogen flow rate and continuously increasing the temperature, it is finally nitrided at 1550℃ for 3h to obtain carbon-containing AlN, which is placed in a decarburization furnace and decarburized at 800℃ / 2h under a reducing atmosphere of H2 to obtain nano-AlN / phlogopite. After wet ball milling at 60rpm for 30min, it is sieved through a 1340 mesh sieve to obtain nano-scale AlN / phlogopite. 10 1.47μm, D 50 3.82μm, D 90 7.95μm; Meanwhile, prepare Ag(2E4MI)2Ac complex solution: add 0.02 mol of 2-ethyl-4-methylimidazole 2E4MI and 0.01 mol of silver acetate AgAc into 400 mL of dichloromethane at room temperature, and stir magnetically at a speed of 240 r / min until the AgAc particles completely disappear to obtain Ag(2E4MI)2Ac complex solution; Step 2: Add 0.3 g of polyvinyl pyrrolidone and 0.2 g of carbon nanotubes to the prepared Ag(2E4MI)2Ac complex solution, ultrasonically disperse at an ultrasonic frequency of 40 kHz / 800 W for 2 h, then add 5 g of the nano-AlN / phlogopite prepared in step 1, and ultrasonically disperse at an ultrasonic frequency of 40 kHz / 800 W for 1 h to obtain a finished dispersion; Step 3: The finished dispersion obtained in step 2 is subjected to reduced pressure distillation to remove dichloromethane, and then the obtained solid is transferred to a muffle furnace and heated to 210° C. for high-temperature sintering for 3 hours to obtain a solid; Step 4: The solid obtained in step 3 is placed in a three-roll mill for three grindings, the roller spacing of the three-roll mill is 10 μm, and the obtained powder is transferred to a planetary ball mill for wet ball milling at a ball mill speed of 60-80 rpm for 30 min, the solid-liquid ratio of ethanol to powder is 1:3, and the semi-finished surface-modified mica composition is obtained by filtering and drying and sieving with 1340 mesh; Step 5: Place 5 g of the semi-finished surface-modified mica composition obtained in step 4 in 200 mL of a 2 wt% KH540 aqueous solution and ultrasonically disperse for 60 min at an ultrasonic frequency of 40 kHz / 800 W, filter, and dry to obtain a finished surface-modified mica composition.

5. A method for preparing a mica composite product for a CCS lithium battery core conductive plate according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: preparing a surface-modified mica composition and a compounded silicone resin with a solid content of 50 wt % respectively; Step 2: The surface-modified mica composition, toughening filler, and compounded silicone resin with a solid content of 50 wt% in step 1, which are accurately measured, are evenly mixed to obtain a mica composite substrate slurry. The obtained mica composite substrate slurry is poured into a forming mold, and after heating to remove the organic solvent, a four-step hot pressing method is used to prepare a semi-finished mica composite substrate. The obtained semi-finished mica composite substrate is heated to 50-55°C at a heating rate of 1-2°C / min and kept warm for 200-300s, and then heated to 80-88°C at a heating rate of 1-2°C / min and kept warm for 60-120min, and naturally cooled to obtain a finished mica composite substrate; At the same time, the surface of the copper foil is subjected to low-temperature plasma treatment, and ammonia treatment is used for 5-30 minutes at 0-4°C. The surface of the copper foil after the low-temperature plasma treatment is coated with 0.5-1g / dm2 of the compounded silicone resin with a solid content of 50wt% in step 1. 2 After the organic solvent is removed by heating, an organic silica gel film is formed on the surface of the copper foil after low-temperature plasma treatment; Step three: stack an electronic-grade glass cloth between adjacent finished mica composite substrates and preheat and press to form a mica substrate, and cover the surface of the mica substrate with the copper foil stacked in step two. The organic silicone film on the surface of the copper foil is in contact with the surface of the mica substrate, and finally perform hot pressing and curing. The mica composite component for the conductive plate of the CCS lithium battery cell can be obtained by hot pressing at a pressure of 2-4 MPa and a temperature of 160-240°C for 2-4 minutes and naturally cooling to room temperature.

6. A method for preparing a mica composite product for a CCS lithium battery core conductive plate according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: preparing a surface-modified mica composition and a compounded silicone resin with a solid content of 50 wt % respectively; In step 2, the surface-modified mica composition, toughening filler, and compounded organic silicone resin with a solid content of 50 wt% obtained in step 1 are uniformly mixed to obtain a mica composite substrate slurry. The obtained mica composite substrate slurry is poured into a forming mold, and after heating to remove the organic solvent, a four-step hot pressing method is used to produce a semi-finished mica composite substrate. The organic solvents are xylene and isopropyl alcohol. The four-step hot pressing method is as follows: in the first step of hot pressing, the hot pressing conditions are a platen temperature of 80°C, a pressure of 0.25 MPa, and a duration of 60 seconds; in the second step of hot pressing, the hot pressing conditions are a platen temperature of 135°C, a pressure of 0. 6Mpa, duration is 120s, the hot pressing conditions in the third step of hot pressing molding are a platen temperature of 180°C, a pressure of 1Mpa, and a duration of 150s; the hot pressing conditions in the fourth step of hot pressing molding are a platen temperature of 120°C, a pressure of 0.6Mpa, and a duration of 80s, and naturally cooled to room temperature to obtain a semi-finished mica composite substrate, the obtained semi-finished mica composite substrate is heated to 50°C at a heating rate of 1°C / min and kept warm for 300s, and then heated to 85°C at a heating rate of 2°C / min and kept warm for 100min, and naturally cooled to obtain a finished mica composite substrate with a thickness of 0.30±0.02mm; At the same time, the surface of the copper foil is subjected to low-temperature plasma treatment, and then treated with ammonia gas at 0°C for 15 minutes. The surface of the copper foil after the low-temperature plasma treatment is coated with 0.6 g / dm2 of the compounded silicone resin with a solid content of 50 wt% in step 1. 2 After heating to remove the organic solvent, the organic solvent is xylene and isopropyl alcohol, that is, the surface of the copper foil after the low-temperature plasma treatment is formed with an organic silica gel film; Step three, take three finished mica composite substrates with a thickness of 0.30±0.02mm, stack an electronic grade glass cloth between adjacent finished mica composite substrates and preheat press to form a mica substrate, the preheat pressing conditions are a pressing plate temperature of 150°C, a pressure of 0.8Mpa, and a duration of 120s; the copper foil in the stacking step 2 is pressed on the surface of the mica substrate formed by preheating, and the organic silicone film on the surface of the copper foil contacts the surface of the mica substrate, and finally hot pressing and curing are performed, hot pressing treatment is carried out at a pressure of 3.2MPa and a temperature of 220°C for 4min, and naturally cooled to room temperature to obtain a mica composite component for the conductive plate of a CCS lithium battery cell.

Images