CN117458059B - Material for vacuum sealing of new energy power battery and preparation method thereof - Google Patents

Abstract

The invention provides a material for vacuum sealing of a new energy power battery and a preparation method thereof, belonging to the technical field of sealing; the preparation process comprises the following steps: preparing glass powder; preparing a phase change material; preparing a composite binder; preparing the sealing composite material. According to the invention, the thermal expansion coefficient of the sealing composite material is improved by adjusting the components and the component contents in the glass powder, the thermal expansion coefficient of the sealing composite material can be further improved by adding Tl ₂ O, the thermal expansion coefficient of the sealing composite material is similar to that of copper, aluminum and the like, and the sealing composite material is free from introducing volatile alkali metal elements Na and K, so that the chemical stability and the structural stability of glass are facilitated, the bonding force between the glass and a base material is improved by adding Al ₂O₃, crystallization is facilitated by adding ZrO ₂, the moisture resistance of the glass is improved, and the sealing strength of the solidified glass is improved.

Description

A material and preparation method for vacuum sealing of new energy power batteries

Technical Field

The present invention relates to the field of sealing technology, and in particular to a material and a preparation method for vacuum sealing of new energy power batteries.

Background Art

In recent years, electric vehicles and other new energy vehicles have become a new trend in the future automotive industry due to their advantages of no pollution, low noise, high energy efficiency, diversification, simple structure, and easy maintenance. In particular, after a decade of development, my country's electric vehicles and other new energy vehicles have initially entered the stage of industrialization from the stage of research and development.

The power battery in electric vehicles and other new energy vehicles is composed of battery cells (also called battery cells), battery stacks composed of battery cells, and modules composed of battery stacks. The battery cell includes a negative electrode tab made of oxygen-free copper or copper alloy, which is electrically insulated and airtightly sealed with the battery aluminum casing.

There are currently three main sealing methods: the first is to use plastic seals, but the sealing plastic will deform after hot injection molding, resulting in reduced airtightness and electrolyte leakage; the second is to use nickel-plated ceramic rings, and then use metal solder to weld the ceramic rings to the tabs and the outer shell respectively. The disadvantage is that the interface bonding of the nickel plating is poor and the welding process is complicated; the third is to use low-melting-point sealing glass for sealing.

However, glass containing silicon dioxide has poor resistance to corrosion by electrolytes. Although bismuth oxide-based glass has high mechanical properties, electrical insulation properties and good corrosion resistance, its thermal expansion coefficient is smaller than that of copper, aluminum, etc., and high temperature and inert gas protection are required during the packaging process. It is prone to cracking after packaging.

Therefore, we proposed a material with a higher thermal expansion coefficient for vacuum sealing of new energy power batteries and a preparation method thereof.

Summary of the invention

In view of the deficiencies in the prior art, the object of the present invention is to provide a material and a preparation method for vacuum sealing of new energy power batteries.

A material for vacuum sealing of new energy power batteries, comprising the following components in parts by weight:

25-30 parts _{of Bi2O3} , 10-30 parts of ZnO, 5-10 parts of _Al2O3 , 2-10 parts of _Li2O , 1-5 parts _{of TiO2} , 1-5 parts of CuO, 3-5 parts of _ZrO2 , 20-30 parts _{of P2O5} , 20-30 parts of _Tl2O , 5-8 parts of composite binder and 3-5 parts of phase change material.

Furthermore, the composite binder comprises the following components in parts by weight:

40-60 parts of epoxy resin, 0.1-0.2 parts of silane coupling agent, 2-3 parts of aluminum oxide powder, 8-10 parts of ethanol-toluene solution, 3-5 parts of methyltetrahydrophthalic anhydride, 0.1-0.2 parts of 3-phenyl-1,1-dimethylurea and 1-2 parts of triphenyl phosphate.

Furthermore, the phase change material comprises the following components in parts by weight:

10-20 parts of paraffin, 30-50 parts of expanded graphite, 1-2 parts of acrylamide, 0.2-0.5 parts of N,N-methylenebispropionamide, 0.1-0.2 parts of polyvinylpyrrolidone, 5-8 parts of distilled water, 0.01-0.05 parts of Tween 85, 0.01-0.03 parts of ammonium persulfate and 0.01-0.05 parts of N,N,N,N-tetramethylethylenediamine.

A material and preparation method for vacuum sealing of new energy power batteries, comprising the following steps:

S1: Preparation of composite binder

Take epoxy resin, add silane coupling agent, aluminum oxide powder and ethanol-toluene solution, add methyltetrahydrophthalic anhydride, 3-phenyl-1,1-dimethylurea and triphenyl phosphate again after ultrasonic mixing, and mix well to obtain a composite adhesive;

S2: Preparation of glass powder

Weigh Bi ₂ O ₃ , ZnO, Al ₂ O ₃ , Li ₂ O, TiO ₂ , CuO, ZrO ₂ , and P ₂ O ₅ , mix and ball-mill, and then melt in a glass melting furnace; pour the molten glass solution into cooling water for water quenching, and then ball-mill and sieve to obtain glass powder;

S3: Preparation of phase change materials

Prepare a paraffin-graphite mixture, mix acrylamide, N,N-methylenebispropionamide and polyvinyl pyrrolidone, add distilled water, add Tween 85 and stir to obtain a mixed aqueous solution, add the paraffin-graphite mixture into the mixed aqueous solution under a water bath, then add ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stir, place in a vacuum drying oven for solidification, and obtain a phase change material;

S4: Preparation of sealing composite materials

Tl ₂ O and glass powder are added to a ball mill to obtain a mixed slurry, the mixed slurry is dried and sieved, and then impregnated with a silane coupling agent, and then a composite adhesive and a phase change material are added and stirred to obtain a sealing composite material.

Furthermore, step S1 prepares the composite adhesive, which specifically includes the following steps:

S1.1: Take 40-60 parts of epoxy resin, add 0.1-0.2 parts of KH560 silane coupling agent, 2-3 parts of aluminum oxide powder and 8-10 parts of ethanol-toluene solution, and mix under ultrasonic stirring for 10-15 minutes to obtain a mixture;

S1.2: Add 3-5 parts of methyltetrahydrophthalic anhydride, 0.1-0.2 parts of 3-phenyl-1,1-dimethylurea and 1-2 parts of triphenyl phosphate to the mixture and mix well to obtain a composite adhesive.

Furthermore, the preparation of the glass powder in step S2 specifically includes the following steps:

S2.1: Weigh 25-30 parts of Bi ₂ O ₃ , 10-30 parts of ZnO, 5-10 parts of Al ₂ O ₃ , 2-10 parts of Li ₂ O, 1-5 parts of TiO ₂ , 1-5 parts of CuO, 3-5 parts of ZrO ₂ , and 20-30 parts of P ₂ O ₅ , sieve the powder through a 50-60 mesh sieve, mix them preliminarily, put them into a ball mill, add agate spheres and 100-120 parts of alcohol, place them in a planetary ball mill, and perform wet ball milling for 2-3 hours to obtain a slurry;

S2.2: The slurry is placed in an oven and dried at 80-85°C for 6-7h, the dried powder is added into a corundum crucible, the crucible is placed in a pre-heated muffle furnace and preheated at 650-700°C for 20-30min, after preheating, it is transferred to a glass melting furnace, heated to 1060-1065°C at a heating rate of 10-15°C/min, heated for 2-3h, and a molten glass solution is obtained;

S2.3: Pour the glass solution directly into cooling water for quenching to obtain glass slag, place the glass slag in a ball mill, add anhydrous ethanol and agate balls, the agate balls: powder ratio is 3-4:1, and wet ball milling is performed for 10-12 hours at a speed of 300-350r/min to obtain glass slurry, dry the glass slurry, and pass through a 100-200 mesh sieve to obtain glass powder.

Furthermore, step S3 prepares the phase change material, which specifically includes the following steps:

S3.1: Add 10-20 parts of paraffin wax into a beaker, raise the temperature to 90-100°C, add 30-50 parts of expanded graphite into the container under mechanical stirring, and mix well with the paraffin wax to obtain a paraffin-graphite mixture;

S3.2: Weigh 1-2 parts of acrylamide, 0.2-0.5 parts of N,N-methylenebispropionamide and 0.1-0.2 parts of polyvinyl pyrrolidone, mix, add 5-8 parts of distilled water, ultrasonically shake until completely dissolved, add 0.01-0.05 parts of Tween 85 and stir until dissolved to obtain a mixed aqueous solution;

S3.3: adding the paraffin-graphite mixture to the mixed aqueous solution at a uniform speed under a 70-75°C water bath condition, and stirring at a high speed for 10-20 minutes to obtain an oil-in-water emulsion;

S3.4: Add 0.01-0.03 parts of ammonium persulfate to the oil-in-water emulsion and stir to disperse, lower the water bath temperature to 50-55°C, add 0.01-0.05 parts of N,N,N,N-tetramethylethylenediamine and stir rapidly for 5-10 minutes, place in a vacuum drying oven at 50-55°C and continue to cure for 5-10 minutes to obtain a phase change material.

Furthermore, step S4 prepares the sealing composite material, which specifically includes the following steps:

S4.1: Take 20-30 parts of Tl ₂ O and 100-120 parts of glass powder, add agate balls and 100-120 parts of alcohol into a ball mill, place in a planetary ball mill, and perform wet ball milling for 2-3 hours, with a ratio of agate balls to powder being 3-4:1, to obtain a mixed slurry;

S4.2: drying the mixed slurry in an oven at 80-85°C for 6-7 hours to obtain a mixed powder, and passing the mixed powder through a 100-200 mesh sieve to obtain glass powder;

S4.3: After impregnating the glass powder with KH560 silane coupling agent for 10-15 minutes, add 5-8 parts of composite adhesive and 3-5 parts of phase change material and stir them in a mixer for 10-20 minutes. After stirring evenly, a sealing composite material is obtained.

Furthermore, in step S1.1, the volume ratio of ethanol to toluene in the ethanol toluene solution is 0.5-2.

Furthermore, in step S2.1, the ratio of agate balls to powder is 3-4:1.

Compared with the prior art, the present invention has at least the following beneficial effects:

1. The present invention improves the thermal expansion coefficient of the sealing composite material by adjusting the components and the content of the components in the glass powder. By adding _Tl2O , the thermal expansion coefficient of the sealing composite material can be further improved, and the thermal expansion coefficient of the sealing composite material can be close to the thermal expansion coefficient of copper, aluminum, etc. The sealing composite material does not introduce volatile alkali metal elements Na and K, which is beneficial to the chemical stability and structural stability of the glass. _The added _Al2O3 improves the bonding force between the glass and the substrate. The addition of _ZrO2 can make crystallization easier, improve the moisture resistance of the glass, and improve the sealing strength of the solidified glass.

2. The present invention can increase the thermal conductivity of the composite adhesive by adding alumina powder to the composite adhesive, which is beneficial to improving the adhesion between the glass and the connector. At the same time, the epoxy resin also has excellent electrical insulation, heat resistance and chemical corrosion resistance. By adding the composite adhesive, the corrosion resistance and thermal conductivity of the sealing composite material can be improved, which is beneficial to the transfer of battery heat.

3. By adding phase change material, the present invention can make the sealing composite material have a certain thermal conductivity and phase change heat storage. The sealing composite material can absorb part of the heat in the heat release process of battery charging and discharging to replace part of the water cooling plate. The energy absorbed when the battery releases heat can be released at low temperature, playing a role of heat preservation in low temperature state.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable those skilled in the relevant art to make and use the present disclosure.

FIG1 is a flow chart of a material and preparation method for vacuum sealing of new energy power batteries used in an embodiment of the present invention;

FIG2 is a comparative table diagram of thermal expansion coefficients of Comparative Example 1 of the present invention;

FIG. 3 is a comparison table of thermal expansion coefficients of Comparative Example 2 of the present invention.

DETAILED DESCRIPTION

The following is a detailed description of a material and preparation method for vacuum sealing of new energy power batteries provided by the present invention in combination with the accompanying drawings and specific embodiments. At the same time, it is explained here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternative methods to implement some known technologies; and the accompanying drawings are only for a more specific description of the embodiments, and are not intended to specifically limit the present invention.

Example 1

A material and preparation method for vacuum sealing of new energy power batteries, as shown in FIG1 , comprises the following steps:

S1: Preparation of composite binder

S1.1: Take 40 parts of epoxy resin, add 0.1 parts of KH560 silane coupling agent, 2 parts of aluminum oxide powder and 8 parts of ethanol-toluene solution, mix for 10 minutes under ultrasonic stirring to obtain a mixture, wherein the volume ratio of ethanol to toluene is 0.5;

S1.2: Add 3 parts of methyltetrahydrophthalic anhydride, 0.1 parts of 3-phenyl-1,1-dimethylurea and 1 part of triphenyl phosphate to the mixture and mix well to obtain a composite adhesive.

S2: Preparation of glass powder

S2.1: Weigh 25 parts of Bi ₂ O ₃ , 10 parts of ZnO, 5 parts of Al ₂ O ₃ , 2 parts of Li ₂ O, 1 part of TiO ₂ , 1 part of CuO, 3 parts of ZrO ₂ , and 20 parts of P ₂ O ₅ , sieve the powder through a 50-mesh sieve, mix them initially, put them into a ball mill, add agate balls and 100 parts of alcohol, place them in a planetary ball mill, and perform wet ball milling for 2 hours, with a ratio of agate balls to powder being 3:1, to obtain a slurry;

S2.2: The slurry is placed in an oven and dried at 80°C for 6 hours. The dried powder is added into a corundum crucible. The crucible is placed in a preheated muffle furnace and preheated at 650°C for 20 minutes. After preheating, the crucible is transferred to a glass melting furnace and heated to 1060°C at a heating rate of 10°C/min for 2 hours to obtain a molten glass solution.

S2.3: Pour the glass solution directly into cooling water for quenching to obtain glass slag, place the glass slag in a ball mill, add anhydrous ethanol and agate balls, the agate balls: powder ratio is 3:1, and wet ball milling is performed for 10 hours at a speed of 300r/min to obtain glass slurry, dry the glass slurry, and pass through a 100-mesh sieve to obtain glass powder.

S3: Preparation of phase change materials

S3.1: Add 10 parts of paraffin wax into a beaker, heat it to 90°C, add 50 parts of expanded graphite into the container under mechanical stirring, mix well with the paraffin wax, and obtain a paraffin-graphite mixture;

S3.2: Weigh 1 part of acrylamide, 0.2 parts of N,N-methylenebispropionamide and 0.1 parts of polyvinyl pyrrolidone, mix them, add 5 parts of distilled water, shake them ultrasonically until they are completely dissolved, add 0.01 parts of Tween 85 and stir until they are dissolved, to obtain a mixed aqueous solution;

S3.3: adding the paraffin-graphite mixture to the mixed aqueous solution at a uniform speed under a 70°C water bath condition, and stirring at a high speed for 10 min to obtain an oil-in-water emulsion;

S3.4: Add 0.01 parts of ammonium persulfate to the oil-in-water emulsion and stir to disperse, lower the water bath temperature to 50°C, add 0.01 parts of N,N,N,N-tetramethylethylenediamine and stir rapidly for 5 minutes, place in a vacuum drying oven at 50°C and continue to cure for 5 minutes to obtain a phase change material.

S4: Preparation of sealing composite materials

S4.1: Take 20 parts of Tl ₂ O and 100 parts of glass powder, add agate balls and 100 parts of alcohol into a ball mill, place in a planetary ball mill, and perform wet ball milling for 2 hours, with a ratio of agate balls to powder being 3:1, to obtain a mixed slurry;

S4.2: drying the mixed slurry in an oven at 80° C. for 6 h to obtain a mixed powder, and passing the mixed powder through a 100-mesh sieve to obtain glass powder;

S4.3: After impregnating the glass powder with KH560 silane coupling agent for 10 minutes, add 5 parts of composite adhesive and 3 parts of phase change material and stir them in a mixer for 10 minutes. After stirring evenly, a sealing composite material is obtained.

Example 2

A material and preparation method for vacuum sealing of new energy power batteries, as shown in FIG1 , comprises the following steps:

S1: Preparation of composite binder

S1.1: Take 60 parts of epoxy resin, add 0.2 parts of KH560 silane coupling agent, 3 parts of aluminum oxide powder and 10 parts of ethanol-toluene solution, mix for 10 minutes under ultrasonic stirring to obtain a mixture, wherein the volume ratio of ethanol to toluene is 2;

S1.2: Add 5 parts of methyltetrahydrophthalic anhydride, 0.2 parts of 3-phenyl-1,1-dimethylurea and 2 parts of triphenyl phosphate to the mixture and mix well to obtain a composite adhesive.

S2: Preparation of glass powder

S2.1: Weigh 30 parts of Bi ₂ O ₃ , 30 parts of ZnO, 10 parts of Al ₂ O ₃ , 10 parts of Li ₂ O, 5 parts of TiO ₂ , 5 parts of CuO, 5 parts of ZrO ₂ , and 30 parts of P ₂ O ₅ , sieve the powder through a 50-mesh sieve, mix them initially, put them into a ball mill, add agate balls and 120 parts of alcohol, place them in a planetary ball mill, and perform wet ball milling for 2 hours, with a ratio of agate balls to powder being 4:1, to obtain a slurry;

S2.2: The slurry is placed in an oven and dried at 80°C for 6 hours. The dried powder is added into a corundum crucible. The crucible is placed in a preheated muffle furnace and preheated at 650°C for 20 minutes. After preheating, the crucible is transferred to a glass melting furnace and heated to 1060°C at a heating rate of 10°C/min for 2 hours to obtain a molten glass solution.

S2.3: Pour the glass solution directly into cooling water for quenching to obtain glass slag, place the glass slag in a ball mill, add anhydrous ethanol and agate balls, the agate ball: powder ratio is 4:1, and wet ball milling is performed for 10 hours at a speed of 300r/min to obtain glass slurry, dry the glass slurry, and pass through a 100-mesh sieve to obtain glass powder.

S3: Preparation of phase change materials

S3.1: Add 20 parts of paraffin wax into a beaker, heat it to 90°C, add 50 parts of expanded graphite into the container under mechanical stirring, mix well with the paraffin wax, and obtain a paraffin-graphite mixture;

S3.2: Weigh 2 parts of acrylamide, 0.5 parts of N,N-methylenebispropionamide and 0.2 parts of polyvinyl pyrrolidone, mix, add 8 parts of distilled water, shake by ultrasound until completely dissolved, add 0.01 parts of Tween 85 and stir until dissolved, to obtain a mixed aqueous solution;

S3.3: adding the paraffin-graphite mixture to the mixed aqueous solution at a uniform speed under a 70°C water bath condition, and stirring at a high speed for 10 min to obtain an oil-in-water emulsion;

S3.4: Add 0.03 parts of ammonium persulfate to the oil-in-water emulsion and stir to disperse, lower the water bath temperature to 50°C, add 0.05 parts of N,N,N,N-tetramethylethylenediamine and stir rapidly for 5 minutes, place in a vacuum drying oven at 50°C and continue to cure for 5 minutes to obtain a phase change material.

S4: Preparation of sealing composite materials

S4.1: Take 30 parts of Tl ₂ O and 120 parts of glass powder, add agate balls and 120 parts of alcohol into a ball mill, place in a planetary ball mill, and perform wet ball milling for 2 hours, with a ratio of agate balls to powder being 4:1, to obtain a mixed slurry;

S4.2: drying the mixed slurry in an oven at 80° C. for 6 h to obtain a mixed powder, and passing the mixed powder through a 100-mesh sieve to obtain glass powder;

S4.3: After impregnating the glass powder with KH560 silane coupling agent for 10 minutes, add 8 parts of composite adhesive and 5 parts of phase change material and stir them in a mixer for 10 minutes. After stirring evenly, a sealing composite material is obtained.

Example 3

A material and preparation method for vacuum sealing of new energy power batteries, as shown in FIG1 , comprises the following steps:

S1: Preparation of composite binder

S1.1: Take 40 parts of epoxy resin, add 0.1 parts of KH560 silane coupling agent, 2 parts of aluminum oxide powder and 8 parts of ethanol-toluene solution, mix for 15 minutes under ultrasonic stirring to obtain a mixture, wherein the volume ratio of ethanol to toluene is 0.5;

S1.2: Add 3 parts of methyltetrahydrophthalic anhydride, 0.1 parts of 3-phenyl-1,1-dimethylurea and 1 part of triphenyl phosphate to the mixture and mix well to obtain a composite adhesive.

S2: Preparation of glass powder

S2.1: Weigh 25 parts of Bi ₂ O ₃ , 10 parts of ZnO, 5 parts of Al ₂ O ₃ , 2 parts of Li ₂ O, 1 part of TiO ₂ , 1 part of CuO, 3 parts of ZrO ₂ , and 20 parts of P ₂ O ₅ , sieve the powder through a 60-mesh sieve, mix them initially, put them into a ball mill, add agate balls and 100 parts of alcohol, place them in a planetary ball mill, and perform wet ball milling for 3 hours, with a ratio of agate balls to powder being 3:1, to obtain a slurry;

S2.2: The slurry is placed in an oven and dried at 85°C for 7 hours. The dried powder is added into a corundum crucible. The crucible is placed in a preheated muffle furnace and preheated at 700°C for 30 minutes. After preheating, the crucible is transferred to a glass melting furnace and heated to 1065°C at a heating rate of 10-15°C/min for 2 hours to obtain a molten glass solution.

S2.3: Pour the glass solution directly into cooling water for quenching to obtain glass slag. Place the glass slag in a ball mill and add anhydrous ethanol and agate balls (the ratio of agate balls to powder is 3:1). Perform wet ball milling for 12 hours at a speed of 350 r/min to obtain glass slurry. Dry the glass slurry and pass it through a 200-mesh sieve to obtain glass powder.

S3: Preparation of phase change materials

S3.1: Add 10 parts of paraffin wax into a beaker, heat it to 100°C, add 50 parts of expanded graphite into the container under mechanical stirring, mix well with the paraffin wax, and obtain a paraffin-graphite mixture;

S3.2: Weigh 1 part of acrylamide, 0.2 parts of N,N-methylenebispropionamide and 0.1 parts of polyvinyl pyrrolidone, add 5 parts of distilled water, shake with ultrasound until completely dissolved, add 0.05 parts of Tween 85 and stir until dissolved to obtain a mixed aqueous solution;

S3.3: adding the paraffin-graphite mixture to the mixed aqueous solution at a uniform speed under a 75°C water bath condition, and stirring at a high speed for 20 min to obtain an oil-in-water emulsion;

S3.4: Add 0.01 parts of ammonium persulfate to the oil-in-water emulsion and stir to disperse, lower the water bath temperature to 55°C, add 0.01 parts of N,N,N,N-tetramethylethylenediamine and stir rapidly for 10 minutes, place in a vacuum drying oven at 55°C and continue to cure for 10 minutes to obtain a phase change material.

S4: Preparation of sealing composite materials

S4.1: Take 20 parts of Tl ₂ O and 100 parts of glass powder, add agate balls and 100 parts of alcohol into a ball mill, place in a planetary ball mill, and perform wet ball milling for 3 hours, with a ratio of agate balls to powder being 3:1, to obtain a mixed slurry;

S4.2: drying the mixed slurry in an oven at 85°C for 7 hours to obtain a mixed powder, and passing the mixed powder through a 100-200 mesh sieve to obtain glass powder;

S4.3: After impregnating the glass powder with KH560 silane coupling agent for 15 minutes, add 5-8 parts of composite adhesive and 3-5 parts of phase change material and stir them in a stirrer for 20 minutes. After stirring evenly, a sealing composite material is obtained.

Comparative Example 1

Compared with Example 1, the difference of Comparative Example 1 is that Comparative Example 1 is commercially available glass powder, specifically glass powder sold by Chenmin Mineral Products Processing Plant, recorded as Comparative Example 1.

The same mass of the sealing composite materials prepared in Example 1, Example 2 and Example 3 and the glass powder of Comparative Example 1 were taken, and the thermal expansion coefficients of the sealing composite materials prepared in Example 1, Example 2 and Example 3 and the thermal expansion coefficient of the glass powder of Comparative Example 1 were tested respectively by using the test method for the linear expansion coefficient of electric vacuum glass disclosed in SJ689-83. The tests were conducted twice in parallel. With reference to FIG2 for the test results, it can be seen that the thermal expansion coefficients of the embodiments are higher than those of the comparative examples. The thermal expansion coefficients of the embodiments are around 215×10 ^-7 /°C, which is relatively close to the thermal expansion coefficients of copper, aluminum, etc., proving that the sealing composite materials prepared by the preparation process of the embodiments have a higher thermal expansion coefficient.

Comparative Example 2

Compared with Example 1, the difference of Comparative Example 2 is that Comparative Example 2 removes steps S4.1-S4.2, replaces the glass powder in step S4.3 with the glass powder in S2.3 of equal mass, and prepares the sealing composite material without changing the other steps, which is recorded as Comparative Example 2.

Using the experimental data obtained in Example 1, Example 2, and Example 3, the sealing composite material prepared in Comparative Example 2 with the same mass as that of the example was taken, and the thermal expansion coefficient of the sealing composite material prepared in Comparative Example 2 was tested using the test method for the linear expansion coefficient of electric vacuum glass disclosed in SJ689-83. The test was conducted twice in parallel. The test results are shown in Figure 3. It can be seen that the thermal expansion coefficients of the examples are higher than those of the comparative examples, indicating that the addition of _Tl2O can increase the thermal expansion coefficient of the sealing composite material.

The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims (7)

1. A material for vacuum sealing of new energy power batteries, characterized in that it comprises the following components in parts by weight: 25-30 parts of Bi ₂ O ₃ , 10-30 parts of ZnO, 5-10 parts of Al ₂ O ₃ , 2-10 parts of Li ₂ O, 1-5 parts of TiO ₂ , 1-5 parts of CuO, 3-5 parts of ZrO ₂ , 20-30 parts of P ₂ O ₅ , 20-30 parts of Tl ₂ O, 5-8 parts of composite binder and 3-5 parts of phase change material; The composite binder comprises the following components in parts by weight: 40-60 parts of epoxy resin, 0.1-0.2 parts of silane coupling agent, 2-3 parts of aluminum oxide powder, 8-10 parts of ethanol-toluene solution, 3-5 parts of methyltetrahydrophthalic anhydride, 0.1-0.2 parts of 3-phenyl-1,1-dimethylurea and 1-2 parts of triphenyl phosphate. 2. A material for vacuum sealing of new energy power batteries according to claim 1, characterized in that, in parts by weight, the phase change material comprises the following components: 10-20 parts of paraffin, 30-50 parts of expanded graphite, 1-2 parts of acrylamide, 0.2-0.5 parts of N,N-methylenebispropionamide, 0.1-0.2 parts of polyvinylpyrrolidone, 5-8 parts of distilled water, 0.01-0.05 parts of Tween 85, 0.01-0.03 parts of ammonium persulfate and 0.01-0.05 parts of N,N,N,N-tetramethylethylenediamine. 3. A method for preparing a material for vacuum sealing of a new energy power battery, characterized in that it comprises the following steps: S1: Preparation of composite binder Take epoxy resin, add silane coupling agent, aluminum oxide powder and ethanol-toluene solution, add methyltetrahydrophthalic anhydride, 3-phenyl-1,1-dimethylurea and triphenyl phosphate again after ultrasonic mixing, and mix well to obtain a composite adhesive; S2: Preparation of glass powder Weigh Bi ₂ O ₃ , ZnO, Al ₂ O ₃ , Li ₂ O, TiO ₂ , CuO, ZrO ₂ , and P ₂ O ₅ , mix and ball-mill, and then melt in a glass melting furnace; pour the molten glass solution into cooling water for water quenching, and then ball-mill and sieve to obtain glass powder; S3: Preparation of phase change materials Prepare a paraffin-graphite mixture, mix acrylamide, N,N-methylenebispropionamide and polyvinyl pyrrolidone, add distilled water, add Tween 85 and stir to obtain a mixed aqueous solution, add the paraffin-graphite mixture into the mixed aqueous solution under a water bath, then add ammonium persulfate and N,N,N,N-tetramethylethylenediamine and stir, place in a vacuum drying oven for solidification, and obtain a phase change material; S4: Preparation of sealing composite materials Tl ₂ O and glass powder are added to a ball mill to obtain a mixed slurry, the mixed slurry is dried and sieved, and then impregnated with a silane coupling agent, and then a composite adhesive and a phase change material are added and stirred to obtain a sealing composite material; Step S1: preparing a composite adhesive, specifically comprising the following steps: S1.1: Take 40-60 parts of epoxy resin, add 0.1-0.2 parts of KH560 silane coupling agent, 2-3 parts of aluminum oxide powder and 8-10 parts of ethanol-toluene solution, and mix under ultrasonic stirring for 10-15 minutes to obtain a mixture; S1.2: Add 3-5 parts of methyltetrahydrophthalic anhydride, 0.1-0.2 parts of 3-phenyl-1,1-dimethylurea and 1-2 parts of triphenyl phosphate to the mixture and mix well to obtain a composite adhesive; Step S2: Preparation of glass powder, specifically comprising the following steps: S2.1: Weigh 25-30 parts of Bi ₂ O ₃ , 10-30 parts of ZnO, 5-10 parts of Al ₂ O ₃ , 2-10 parts of Li ₂ O, 1-5 parts of TiO ₂ , 1-5 parts of CuO, 3-5 parts of ZrO ₂ , and 20-30 parts of P ₂ O ₅ , sieve the powder through a 50-60 mesh sieve, mix them preliminarily, put them into a ball mill, add agate spheres and 100-120 parts of alcohol, place them in a planetary ball mill, and perform wet ball milling for 2-3 hours to obtain a slurry; S2.2: The slurry is placed in an oven and dried at 80-85°C for 6-7h, the dried powder is added into a corundum crucible, the crucible is placed in a pre-heated muffle furnace and preheated at 650-700°C for 20-30min, after preheating, it is transferred to a glass melting furnace, heated to 1060-1065°C at a heating rate of 10-15°C/min, heated for 2-3h, and a molten glass solution is obtained; S2.3: Pour the glass solution directly into cooling water for quenching to obtain glass slag, place the glass slag in a ball mill, add anhydrous ethanol and agate balls, the agate balls: powder ratio is 3-4:1, and wet ball milling is performed for 10-12 hours at a speed of 300-350r/min to obtain glass slurry, dry the glass slurry, and pass through a 100-200 mesh sieve to obtain glass powder. 4. The method for preparing a material for vacuum sealing of a new energy power battery according to claim 3, characterized in that step S3 of preparing a phase change material specifically comprises the following steps: S3.1: Add 10-20 parts of paraffin wax into a beaker, raise the temperature to 90-100°C, add 30-50 parts of expanded graphite into the container under mechanical stirring, and mix well with the paraffin wax to obtain a paraffin-graphite mixture; S3.2: Weigh 1-2 parts of acrylamide, 0.2-0.5 parts of N,N-methylenebispropionamide and 0.1-0.2 parts of polyvinyl pyrrolidone, mix, add 5-8 parts of distilled water, ultrasonically shake until completely dissolved, add 0.01-0.05 parts of Tween 85 and stir until dissolved to obtain a mixed aqueous solution; S3.2: adding the paraffin-graphite mixture to the mixed aqueous solution at a uniform speed under a 70-75°C water bath condition, and stirring at a high speed for 10-20 minutes to obtain an oil-in-water emulsion; S3.3: Add 0.01-0.03 parts of ammonium persulfate to the oil-in-water emulsion and stir to disperse, lower the water bath temperature to 50-55°C, add 0.01-0.05 parts of N,N,N,N-tetramethylethylenediamine and stir rapidly for 5-10 minutes, place in a vacuum drying oven at 50-55°C and continue to cure for 5-10 minutes to obtain a phase change material. 5. The method for preparing a material for vacuum sealing of a new energy power battery according to claim 4, characterized in that step S4 prepares the sealing composite material, specifically comprising the following steps: S4.1: Take 20-30 parts of Tl ₂ O and 100-120 parts of glass powder, add agate balls and 100-120 parts of alcohol into a ball mill, place in a planetary ball mill, and perform wet ball milling for 2-3 hours, with a ratio of agate balls to powder being 3-4:1, to obtain a mixed slurry; S4.2: drying the mixed slurry in an oven at 80-85°C for 6-7 hours to obtain a mixed powder, and sifting the mixed powder through a 100-200 mesh sieve to obtain glass powder; S4.3: After impregnating the glass powder with KH560 silane coupling agent for 10-15 minutes, add 5-8 parts of composite adhesive and 3-5 parts of phase change material and stir them in a mixer for 10-20 minutes. After stirring evenly, a sealing composite material is obtained. 6. The method for preparing a material for vacuum sealing of new energy power batteries according to claim 3, characterized in that the volume ratio of ethanol to toluene in the ethanol-toluene solution in step S1.1 is 0.5-2. 7. The method for preparing a material for vacuum sealing of new energy power batteries according to claim 3, characterized in that in step S2.1, the ratio of agate balls to powder is 3-4:1.