Packaging material and preparation method thereof, battery and electric equipment

Abstract

The invention discloses a packaging material and a preparation method thereof, a battery and electric equipment, the packaging material comprises a substrate and a coating, the coating is arranged on the surface of one side of the substrate in the thickness direction, and the coating comprises a compound with a glycidyl group. According to the packaging material disclosed by the invention, the coating can specifically absorb carbon dioxide generated in the long-term operation process of the battery, so that the gas expansion phenomenon of the battery and the safety risk caused by the gas expansion phenomenon are relieved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a packaging material and a preparation method thereof, a battery and an electrical device. Background Art

[0002] In traditional technology, the aluminum-plastic film of soft-pack batteries is usually composed of an outer resistance layer, a barrier layer and a high barrier layer, which protects the internal structure of the battery cell, prevents the invasion of external air and moisture, and prevents corrosion and leakage of the electrolyte. The various layers of the aluminum-plastic film are compounded by a binder. However, when the battery is in long-term working condition, the electrode material and the electrolyte gradually age and degrade, and gas is continuously generated, causing the battery to bulge. The aluminum-plastic film packaging does not have the ability to withstand large internal pressure, and there are safety hazards in the battery. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to provide a packaging material, the coating of which can specifically absorb the carbon dioxide generated during the long-term operation of the battery, thereby alleviating the battery bloating phenomenon and the resulting safety risks.

[0004] The second objective of the present invention is to provide a method for preparing a packaging material.

[0005] The third object of the present invention is to provide a battery using the above packaging material.

[0006] A fourth object of the present invention is to provide an electrical device using the battery.

[0007] The packaging material according to the first aspect of the present invention comprises: a substrate; and a coating, wherein the coating is provided on one side surface of the substrate in the thickness direction, and the coating comprises a compound having an epoxypropyl group.

[0008] The packaging material according to the first aspect of the present invention has a simple structure and is easy to use by adopting the packaging material of the present application. When the packaging material is used in a battery, the coating can absorb carbon dioxide generated by the degradation of the electrolyte at room temperature and pressure to effectively alleviate the battery flatulence phenomenon and the safety risks caused by the flatulence, thereby improving the safety performance of the battery and extending the service life of the battery.

[0009] According to some embodiments of the present invention, the compound having an epoxypropyl group is a compound of the following structural formula (1):

[0010] Formula (1).

[0011] According to some embodiments of the present invention, in formula (1), m is a natural number between 2 and 10,000, and n is a natural number between 2 and 10,000.

[0012] According to some embodiments of the present invention, in formula (1), R1 and R2 are independently selected from hydrogen, methyl, ethyl, propyl, butyl, phenyl, methyl ester, ethyl ester, propyl ester, α-pyrrolidone, methoxy, ethoxy, butoxy, diisopropoxysilylpropyl, trimethoxysilylpropyl, triethoxysilylpropyl, 15-crown-5 group, 18-crown-6 group or 12-crown-4 group.

[0013] According to some embodiments of the present invention, in formula (1), R1 and R2 are independently selected from methyl, ethyl, propyl, carbomethoxy, carboethoxy, methoxy or trimethoxysilylpropyl.

[0014] According to some embodiments of the present invention, the thickness of the coating is d, wherein d satisfies: 25um≤d≤75um.

[0015] According to some embodiments of the present invention, the substrate comprises an aluminum-plastic film.

[0016] A method for preparing a packaging material according to the first embodiment of the present invention comprises the following steps: The solution of the compound having the epoxypropyl group is coated on one surface of the substrate in the thickness direction, and dried and solidified to form the packaging material having the coating layer.

[0017] According to some embodiments of the present invention, the preparation method of the compound having a glycidyl group is as follows: The compound having the glycidyl group is obtained by polymerizing glycidyl methacrylate with an ethylenic monomer.

[0018] According to some embodiments of the present invention, preparing the solution of the compound having a glycidyl group comprises the following steps: A dispersant and the compound having a glycidyl group are mixed to obtain a solution of the compound having a glycidyl group.

[0019] According to some embodiments of the present invention, mixing the dispersant and the compound having a glycidyl group specifically comprises: The dispersant is dissolved in the first solvent to obtain a first solution, and the first solution and the compound having a glycidyl group are mixed.

[0020] According to some embodiments of the present invention, dissolving the dispersant in the first solvent to obtain the first solution specifically includes: The dispersant is dissolved in the first solvent, and a catalyst is added to obtain the first solution.

[0021] According to some embodiments of the present invention, the mass ratio of the dispersant, the first solvent and the catalyst is (10-20): (80-200): (5-10).

[0022] According to some embodiments of the present invention, the catalyst includes azobisisobutyronitrile and / or an alkali metal salt.

[0023] According to some embodiments of the present invention, the alkali metal salt includes at least one of LiBr, LiCl, LiI, KBr and KCl.

[0024] According to some embodiments of the present invention, the mixing temperature is 60° C. to 80° C., and the mixing time is 8 h to 24 h.

[0025] According to some embodiments of the present invention, the first solvent includes at least one of ethanol, methanol, diethyl ether and toluene.

[0026] According to some embodiments of the present invention, the polymerizing reaction of glycidyl methacrylate with an ethylenic monomer comprises mixing the glycidyl methacrylate with the ethylenic monomer and a second solvent to perform the polymerization reaction.

[0027] According to some embodiments of the present invention, the second solvent includes at least one of N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide and tetrahydrofuran.

[0028] According to some embodiments of the present invention, the polymerization reaction temperature is 60° C. to 80° C., and the polymerization reaction time is 8 h to 24 h.

[0029] According to some embodiments of the present invention, the vinyl monomer includes at least one of methyl acrylate, ethyl acrylate, methyl methacrylate, butyl acrylate, styrene, 3-(trimethoxysilyl)propyl methacrylate and N-vinyl pyrrolidone.

[0030] The battery according to the third aspect of the present invention comprises the packaging material according to the first aspect of the present invention, or the packaging material prepared by the method for preparing the packaging material according to the second aspect of the present invention.

[0031] An electrical device according to an embodiment of the fourth aspect of the present invention comprises a battery according to the embodiment of the third aspect.

[0032] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are described in detail below. The packaging material according to the embodiments of the first aspect of the present invention is described in detail below.

[0034] The packaging material according to the first aspect of the embodiment of the present invention includes a substrate coating.

[0035] Specifically, the coating is disposed on one side surface of the substrate in the thickness direction, and the coating includes a compound having a glycidyl group. For example, when the packaging material is used in a battery, the packaging material can protect the internal electrode and isolate it from the external environment. In order to facilitate the coating to function, the coating can be disposed on the inner side of the substrate. In this way, the glycidyl group on the compound having a glycidyl group in the coating can absorb carbon dioxide generated by the degradation of the electrolyte to generate cyclic carbonate, so as to effectively alleviate the battery flatulence phenomenon and the safety risks caused by the flatulence, thereby improving the safety performance of the battery and extending the service life of the battery.

[0036] The packaging material according to the first aspect of the present invention has a simple structure and is easy to use by using the packaging material of the present application. When the packaging material is used in a battery, the coating can absorb carbon dioxide generated by the degradation of the electrolyte to effectively alleviate the battery bloating phenomenon and the safety risks caused by bloating, thereby improving the safety performance of the battery and extending the service life of the battery.

[0037] According to some embodiments of the present invention, the compound having an epoxypropyl group is a compound having the following structural formula (1):

[0038] Formula (1).

[0039] For example, the substrate can be a packaging material product with a three-layer structure of an outer resistance layer, a barrier layer and a high barrier layer commonly seen in traditional technology. That is to say, a conventional packaging material can be purchased as the substrate in this application, and a polymer solution is applied to the inner surface of the substrate in the thickness direction to form a coating. The above-mentioned "inner surface" refers to the surface of the side of the substrate facing the inside of the battery when the substrate is used in the battery. Therefore, by setting the coating to be formed on the inner side of the substrate, the coating can directly contact the gas inside the battery, thereby improving the gas absorption effect of the packaging material.

[0040] In addition, by using a coating of a compound having the above-mentioned general structural formula (1), the above-mentioned compound has a glycidyl group, and the glycidyl group can absorb carbon dioxide generated by the degradation of the electrolyte to generate a cyclic carbonate. When the packaging material is used in a battery, it can effectively alleviate the battery bloating phenomenon and the safety risks caused by bloating, thereby improving the safety performance of the battery and extending the service life of the battery. For example, the reaction formula of the compound having the above-mentioned general structural formula (1) and carbon dioxide is as follows:

[0041] According to some embodiments of the present invention, in formula (1), m is a natural number of 2 to 10000, and n is a natural number of 2 to 10000. In this way, the molecular weight of the compound in formula (1) is reasonably designed, which is beneficial to the preparation of the compound having the epoxypropyl group, thereby facilitating the preparation of the coating, improving the production efficiency, and further facilitating the production and processing of the packaging material.

[0042] According to some embodiments of the present invention, in formula (1), R1 and R2 are independently selected from hydrogen, methyl, ethyl, propyl, butyl, phenyl, methyl ester, ethyl ester, propyl ester, α-pyrrolidone, methoxy, ethoxy, butoxy, diisopropoxysilylpropyl, trimethoxysilylpropyl, triethoxysilylpropyl, 15-crown-5 group, 18-crown-6 group or 12-crown-4 group.

[0043] For example, 15-crown-5 is a macrocyclic polyether compound with a CAS number of 33100-27-5. 18-crown-6 has a macrocyclic ether structure, a ring molecule composed of 12 atoms, 6 of which are oxygen atoms and 6 are carbon atoms. The cavity in the molecule is of moderate size, and its CAS number is 17455-13-9. The CAS number of 12-crown-4 is 294-93-9.

[0044] In this way, the compound of the general structural formula (1) having the above substituents is not likely to have other effects on the coating, which is conducive to setting the coating on the substrate for application in the battery. In addition, the structure of the compound of the general structural formula (1) is stable, which is conducive to the long-term function of the coating.

[0045] Preferably, R1 and R2 are independently selected from methyl, ethyl, propyl, carbomethoxy, carboethoxy, methoxy or trimethoxysilylpropyl. Such a configuration is conducive to the preparation of the compound of the general structural formula (1) having the above substituents, and is also more conducive to the stability of the compound, so as to be more conducive to the long-term function of the coating.

[0046] According to some embodiments of the present invention, the thickness of the coating is d, where d satisfies: 25um≤d≤75um. For example, when the thickness of the coating is less than 25um, the mass of the substance that can absorb carbon dioxide on the coating is reduced, reducing the absorption effect of carbon dioxide. When the thickness of the coating is greater than 75um, the coating is too thick, and the substance far from the surface of the coating is difficult to react with the gas, reducing the gas absorption efficiency. Therefore, by setting the thickness of the coating to satisfy 25um≤d≤75um, the thickness of the coating is moderate, which is conducive to the formation of the coating while also helping to improve the gas absorption efficiency.

[0047] According to some embodiments of the present invention, the substrate includes an aluminum-plastic film. For example, the aluminum-plastic film is a high-strength, high-barrier multilayer composite structure material composed of a variety of plastics, aluminum foil and adhesives. It is a special packaging material for soft-pack lithium batteries and blade batteries, which can protect the internal electrodes and isolate the external environment. It is widely used in lithium-ion batteries in the fields of 3C electronic products, new energy vehicles, energy storage, etc. In other words, the substrate can be a commercially available aluminum-plastic film. Of course, the substrate can also be other common materials used for battery packaging to improve the applicability of the packaging material of the present application.

[0048] A method for preparing a packaging material according to the first embodiment of the present invention comprises the following steps: A solution of a compound having an epoxypropyl group is placed on one surface of the substrate in the thickness direction, dried and solidified to form a packaging material having a coating layer.

[0049] For example, the above-mentioned solution of the compound with epoxypropyl group is arranged (specifically can be coated) on the inner side of the thickness direction of matrix (can be the aluminum plastic film available on the market).The method of coating can be spraying, dip coating, spin coating etc., and the specific method depends on the thickness of the coating of the shape, size and requirement of matrix.The process of drying and curing is to volatilize the solvent in the solution, and polymer forms a solid coating.Drying can be carried out by modes such as natural drying, heat drying or ventilation drying.In addition, the preparation method of encapsulating material is simple to operate, and operating conditions are easy to control, which helps the production and processing of encapsulating material.

[0050] With such arrangement, it is only necessary to apply the above solution and then dry and solidify it. The preparation method of the packaging material is simple and the operation process is easy, which is conducive to the preparation and mass production of the packaging material.

[0051] According to some embodiments of the present invention, the preparation method of the compound having a glycidyl group is as follows: The compound having a glycidyl group is obtained by polymerizing glycidyl methacrylate with an ethylenic monomer.

[0052] The polymerization reaction of glycidyl methacrylate and vinyl monomers includes mixing glycidyl methacrylate, vinyl monomers and a second solvent to carry out polymerization reaction.

[0053] For example, glycidyl methacrylate and an olefinic monomer are added to a second solvent to obtain a second solution, wherein glycidyl methacrylate and an olefinic monomer undergo a polymerization reaction to obtain a compound having a glycidyl group. The second solvent includes at least one of N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide and tetrahydrofuran, and the second solvent as an organic polar solvent can promote the dissolution of the polymer monomer. For example, glycidyl methacrylate contains an epoxy group and an acrylate group and has a high reactivity. An olefinic monomer can undergo a polymerization reaction with glycidyl methacrylate. Thus, the compound having the general structural formula (1) is obtained by the polymerization reaction of glycidyl methacrylate and an olefinic monomer, and the preparation method is simple and easy to operate.

[0054] According to some embodiments of the present invention, preparing a solution of a compound having a glycidyl group comprises the following steps: The dispersant and the compound having a glycidyl group are mixed to obtain a solution of the compound having a glycidyl group.

[0055] Mixing the dispersant and the compound having an epoxypropyl group specifically includes: Dissolve the dispersant in the first solvent to obtain a first solution, and mix the first solution with the compound having a glycidyl group. The mixing temperature is 60°C to 80°C, and the mixing time is 8h to 24h. In other words, the dispersant solution is mixed with the compound having a glycidyl group so that the compound having a glycidyl group is dispersed more evenly, which is more conducive to the preparation of the encapsulation material. For example, the first solution is added to the second solution, heated and stirred to obtain a solution of the compound having a glycidyl group.

[0056] According to some embodiments of the present invention, dissolving the dispersant in the first solvent to obtain the first solution specifically includes: The dispersant is dissolved in the first solvent, and then the catalyst is added to obtain the first solution. The mass ratio of the dispersant, the first solvent and the catalyst is (10-20): (80-200): (5-10). In this way, the main function of the dispersant is to uniformly disperse the compounds in the solution of the compound having the glycidyl group to prevent agglomeration and precipitation. In addition, the dispersant helps the uniform mixing and stable existence of various components in the subsequent steps. The first solvent is conducive to the full dissolution of the dispersant to form a stable first solution. In addition, the first solution is added to the second solution to mix the dispersant with the glycidyl methacrylate and the olefin monomer being polymerized. This process can promote uniform mixing by stirring, ultrasound, etc. In addition, heating can increase the reaction rate and promote the polymerization reaction. Stirring helps to maintain the uniformity of the solution and prevent local overheating or uneven reaction. During the heating and stirring process, the molecular weight of the polymer gradually increases to form a polymer solution. For example, the dispersant includes polyvinyl pyrrolidone (PVP), dimethylformamide (DMF) or dimethyl sulfoxide (DMSO).

[0057] The polymer solution is applied to the inner side surface in the thickness direction of the substrate (which can be a commercially available packaging material). The coating method can be spraying, dipping, spin coating, etc., and the specific method depends on the shape, size and required coating thickness of the substrate. The drying and curing process is to evaporate the solvent in the polymer solution, and the polymer forms a solid coating. Drying can be carried out by natural drying, heating drying or ventilation drying. In addition, the preparation method of the packaging material is simple to operate, and the operating conditions are easy to control, which is beneficial to the production and processing of the packaging material. It should be noted that the preparation order of the first solution and the second solution is not limited. In the above steps, the reaction formula of glycidyl methacrylate and olefin monomer is as follows:

[0058] Preferably, the method for preparing the packaging material comprises the following steps: S1, dissolving a dispersant in a first solvent, and then adding a catalyst to obtain a first solution; S2, adding glycidyl methacrylate and an olefinic monomer into a second solvent to obtain a second solution, wherein the glycidyl methacrylate and the olefinic monomer undergo a polymerization reaction to obtain a compound having a structural formula (1); S3, adding the first solution to the second solution, heating and stirring to obtain a polymer solution; S4, coating the polymer solution on the inner side surface in the thickness direction of the substrate, drying and curing the solution to form an aluminum-plastic film with a coating.

[0059] Of course, the order of the above steps S1 and S2 is not limited to this. The above step order is only used as an example for explanation.

[0060] According to some embodiments of the present invention, the vinyl monomer includes at least one of methyl acrylate, ethyl acrylate, methyl methacrylate, butyl acrylate, styrene, 3-(trimethoxysilyl)propyl methacrylate and N-vinyl pyrrolidone.

[0061] For example, methyl acrylate contains an acrylate group, has an unsaturated double bond, and can undergo free radical polymerization. It can increase the flexibility and weather resistance of the polymer, allowing the coating to maintain good flexibility at low temperatures. At the same time, the ester group of methyl acrylate can improve the adhesion between the polymer and the substrate. The structure of ethyl acrylate is similar to that of methyl acrylate, but due to the presence of the ethyl group, the flexibility of its polymer may be better. In the coating, it can enhance the water resistance and chemical corrosion resistance of the coating, and its longer carbon chain structure helps to improve the hydrophobicity of the polymer.

[0062] Methyl methacrylate also has unsaturated double bonds and contains methyl and methyl ester groups. It can give the polymer higher hardness and wear resistance, making the coating more durable. At the same time, it can also improve the light resistance and weather resistance of the coating. Butyl acrylate contains a longer butyl chain in its structure, which makes its polymer more flexible and impact resistant. In the coating, it can increase the elasticity and impact resistance of the coating. The presence of the butyl chain also makes the polymer have better low temperature resistance. Styrene has aromatic rings and unsaturated double bonds and can undergo free radical polymerization. It can improve the hardness, strength and heat resistance of the polymer. At the same time, the presence of the aromatic ring can also improve the chemical corrosion resistance of the polymer. 3-(Trimethoxysilyl)propyl methacrylate contains silyl and acrylate groups and can undergo free radical polymerization. It can give the polymer good adhesion and water resistance. The silyl group can form a chemical bond with the surface of the substrate to improve the bonding strength between the coating and the substrate. At the same time, the presence of the trimethoxy group can increase the crosslinking density of the polymer and improve the water resistance and chemical corrosion resistance of the coating. N-vinylpyrrolidone contains a five-membered ring lactam structure and an unsaturated double bond, which can undergo free radical polymerization. It can increase the solubility and biocompatibility of polymers. At the same time, it can also improve the thermal stability and antioxidant properties of polymers.

[0063] According to some embodiments of the present invention, dissolving the dispersant in the first solvent to obtain the first solution specifically includes: dissolving the dispersant in the first solvent, stirring to dissolve, and then adding a catalyst and stirring to obtain the first solution. Thus, stirring is conducive to more fully dissolving the dispersant in the first solvent and improving the dissolution rate. In addition, by adding a catalyst, the polymerization reaction of glycidyl methacrylate and ethylenic monomers can be promoted and the reaction rate can be improved.

[0064] According to some embodiments of the present invention, dissolving the dispersant in the first solvent, stirring to dissolve, and then adding the catalyst, stirring to obtain the first solution specifically includes: adding 10g~20g of the dispersant to 80g~200g of the first solvent, stirring to dissolve, and then adding 5g~10g of the catalyst, stirring for 8h~24h until completely dissolved. In this way, the addition amount of the dispersant, the first solvent and the catalyst, the stirring time, etc. are reasonably set, which is conducive to the dissolution of the dispersant and the smooth progress of the polymerization reaction, thereby facilitating the preparation of the packaging material. Specifically, in step S2, 50~100g of methyl acrylate / ethyl acrylate / methyl methacrylate / butyl acrylate / styrene / 3-(trimethoxysilyl) propyl methacrylate / N-vinyl pyrrolidone and 50~100g of glycidyl methacrylate are slowly added to 150~250g NMP (N-methylpyrrolidone), and heated and stirred at 60~80°C for 8~24h until completely dissolved. In the above step S4, the substrate needs to be pre-treated, and the pre-treatment process is as follows: after wiping and cleaning the substrate with anhydrous ethanol, bake it in a vacuum oven at 80° C. for 24 hours.

[0065] According to some embodiments of the present invention, the catalyst includes azobisisobutyronitrile (AIBN) and / or an alkali metal salt. Under heating conditions, AIBN decomposes to generate free radicals, thereby initiating a polymerization reaction between an olefin monomer and glycidyl methacrylate. The generated free radicals can attack the double bonds in the monomer molecules to form active centers, thereby initiating a polymerization reaction. The decomposition temperature of AIBN as a catalyst is moderate, usually around 60-80°C, and the reaction conditions are easy to control. Moreover, the initiation efficiency is high, and sufficient free radicals can be quickly generated to initiate the polymerization reaction. It has a wide range of applications and can be used for the polymerization of a variety of olefin monomers. Alkali metal salts can be used as ion catalysts to initiate polymerization reactions through ion reactions. For example, metal ions in alkali metal salts can coordinate with certain groups in monomer molecules to form active centers, thereby initiating polymerization reactions. Using alkali metal salts as catalysts can initiate polymerization reactions under relatively mild conditions, and the requirements for reaction temperature and pressure are relatively low. The molecular weight and molecular weight distribution of the polymer can be adjusted, and the fine regulation of the polymerization reaction can be achieved by controlling the concentration and type of alkali metal salts. In addition, the efficiency of the polymerization reaction and the quality of the product can be improved.

[0066] According to some embodiments of the present invention, the alkali metal salt includes at least one of LiBr, LiCl, LiI, KBr and KCl.

[0067] LiBr (lithium bromide) may catalyze polymerization by providing lithium ions. Lithium ions can interact with certain functional groups in the monomers and promote polymerization. The lithium ions in LiCl (lithium chloride) can also interact with the monomers to initiate polymerization. The potassium ions in KBr (potassium bromide) have different ionic properties than lithium ions. The larger radius of potassium ions may have different steric effects on the reaction. Potassium chloride is more stable and easier to use than other alkali metal salts.

[0068] According to some embodiments of the present invention, the temperature of the polymerization reaction is 60°C to 80°C, and the time of the polymerization reaction is 8h to 24h. The temperature of mixing the dispersant and the compound having an epoxypropyl group is 60°C to 80°C, and the time of the mixing reaction is 8h to 24h. Within the above-defined temperature range, the catalyst can effectively play a role in promoting the polymerization reaction between the monomers. For azobisisobutyronitrile (AIBN) as a catalyst, its decomposition temperature is usually around 60-80°C, at which temperature it can stably generate free radicals to initiate polymerization. For alkali metal salt catalysts, appropriate temperature can increase the activity of ions and promote the reaction. This temperature range also helps to control the reaction rate. If the temperature is too low, the reaction rate will slow down and the reaction time will be extended; if the temperature is too high, side reactions may occur, affecting the quality and yield of the product. At the same time, this temperature range is also suitable for maintaining the stability of the reaction system. It will not cause excessive evaporation of the solvent, nor will it cause excessive pressure and damage to the equipment.

[0069] During the polymerization process, the monomers need to fully contact the catalyst and react with each other. Stirring can keep the substances in the reaction system mixed, avoiding local concentrations that are too high or too low, thereby improving the efficiency of the reaction and the quality of the product. With the extension of the stirring time, the polymerization reaction can be carried out more fully. This helps to improve the molecular weight of the polymer and the uniformity of the molecular weight distribution. In the early stage of the reaction, the conversion rate of the monomer is low. As time goes by, the reaction gradually tends to equilibrium and the molecular weight of the polymer will gradually increase. The stirring time of 8h-24h also takes into account the feasibility and economy in actual production. Too long stirring time will increase energy consumption and production costs, while too short a time may lead to incomplete reaction and affect product performance.

[0070] According to some embodiments of the present invention, the first solvent includes at least one of ethanol, methanol, ether and toluene. The second solvent includes at least one of N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide and tetrahydrofuran. In this way, the reagents of the first solvent and the second solvent are easily available, which is conducive to the full dissolution of the dispersant, the vinyl monomer and the glycidyl methacrylate.

[0071] The battery according to the third aspect of the present invention comprises the packaging material according to the first aspect, or the packaging material prepared by the method for preparing the packaging material according to the second aspect.

[0072] According to the battery of the third aspect of the present invention, such as a soft-pack battery, the above-mentioned packaging material is used to improve the performance of the battery and extend the service life of the battery.

[0073] An electrical device according to an embodiment of a fourth aspect of the present invention comprises a battery according to an embodiment of the third aspect.

[0074] According to the electric equipment of the embodiment of the present invention, by adopting the above-mentioned battery, the performance of the electric equipment is improved. For example, the electric equipment includes vehicles, aircraft, ships, computers, energy storage cabinets, etc.

[0075] Other structures and operations of the battery and the electrical device according to the embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0076] The embodiments of the present invention are described in detail below. It should be noted that the embodiments described below are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention. In addition, if not explicitly stated, all reagents used in the following embodiments are commercially available, or can be synthesized according to this article or known methods, and the reaction conditions not listed are also easily available to those skilled in the art.

[0077] The battery of the present invention is described by means of exemplary specific embodiments and comparative examples. The battery performance of the battery made of the packaging materials of the embodiments and comparative examples is tested below.

[0078] Among them, the water displacement method is used to test the battery volume. The water displacement method uses the Archimedes principle to convert the battery mass into volume. The test method for the gas production volume of the battery is as follows: Immerse the battery in water and record the mass m1. After wiping it clean, connect it to the power supply for activation and charge-discharge cycles. After the end, immerse it in water again and record the mass m2. Note that the immersion device and method of the two weight tests should be kept consistent. V=(m1-m2) / ρ 水 Calculate the gas production volume.

[0079] Example 1 The preparation method of the packaging material is as follows: 10 g of polyvinyl pyrrolidone (PVP) was added to 100 g of ethanol and stirred to dissolve. Then, 5 g of AIBN was added to the solution and stirred for 12 hours until it was completely dissolved to obtain a first solution.

[0080] 80 g of methyl methacrylate and 80 g of glycidyl methacrylate were slowly added into 200 g of NMP, heated at 80° C. and stirred at 800 rpm for 16 h until completely dissolved, to obtain a second solution.

[0081] The first solution was added dropwise into the second solution, and the heating temperature was kept at 80° C. and the high-speed stirring was maintained at 800 rpm, and the stirring was continued for 18 h until the reaction was complete, so as to obtain a polymer solution.

[0082] After the polymer solution is cooled to room temperature, it is applied to the inner side of the substrate of the soft-pack battery washed and dried with ethanol, with a coating thickness of 50um (d), and the coating is allowed to dry and solidify at room temperature. Among them, a 4Ah soft-pack battery is prepared using a traditional battery preparation method.

[0083] That is, the method of Example 1 was used to prepare a compound having the following structural formula (1-1):

[0084] Formula (1-1) In formula (1-1), m=7, n=3.

[0085] Example 2 The main difference from Example 1 is that the catalyst is LiBr and NMP is changed to N,N-dimethylformamide (DMF).

[0086] Example 3 The main difference from Example 1 is that the olefin monomer is ethyl acrylate. Correspondingly, a compound having the following structural formula (1-2) is obtained:

[0087] Formula (1-2).

[0088] In formula (1-2), m=3, n=2.

[0089] Example 4 The main difference from Example 1 is that the thickness of the coating is 25 um.

[0090] Example 5 The main difference from Example 1 is that the thickness of the coating is 75 um.

[0091] Example 6 The main difference from Example 1 is that the olefin monomer is methyl acrylate. Correspondingly, a compound having the following structural formula (1-3) is obtained:

[0092] Formula (1-3).

[0093] In formula (1-3), m=3, n=2.

[0094] Example 7 The main difference from Example 1 is that the olefin monomer is 15-crown-5-2-methyl methacrylate. Correspondingly, a compound having the following general structural formula (1-4) is obtained:

[0095] Formula (1-4).

[0096] In formula (1-4), m=3, n=2.

[0097] Comparative Example 1 A 4Ah soft pack battery was prepared using a commercially available aluminum-plastic film, that is, the surface of the aluminum-plastic film had no coating.

[0098] The test results of the battery gas production volume of the above-mentioned Examples 1-7 and Comparative Example 1 are shown in Table 1.

[0099] Table 1 Battery performance test results of Examples 1-7 and Comparative Example 1

[0100] As shown in Table 1, the gas generation volume of the battery produced by the packaging material of the present application is significantly reduced compared with that of the battery produced in Comparative Example 1, indicating that the packaging material of the present application can better absorb the gas generated by the battery to alleviate the battery bloating phenomenon and the safety risks caused. By comparing Example 1, Example 3, Example 6 and Example 7, it can be seen that the performance test results of Example 1, Example 3 and Example 6 are better than those of Example 7.

[0101] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships that are based on orientation or positional relationships and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0102] In the description of the present invention, "plurality" means two or more.

[0103] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0104] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A packaging material, characterized in that: include: matrix; A coating layer is provided on one side surface of the substrate in a thickness direction, and the coating layer includes a compound having a glycidyl group.

2. The packaging material according to claim 1, characterized in that: The compound having an epoxypropyl group is a compound of the following general structural formula (1): Formula (1).

3. The packaging material according to claim 2, characterized in that: In formula (1), m is a natural number between 2 and 10,000, and n is a natural number between 2 and 10,000.

4. The packaging material according to claim 2, characterized in that: In formula (1), R1 and R2 are independently selected from hydrogen, methyl, ethyl, propyl, butyl, phenyl, methyl ester, ethyl ester, propyl ester, α-pyrrolidone, methoxy, ethoxy, butoxy, diisopropoxysilylpropyl, trimethoxysilylpropyl, triethoxysilylpropyl, 15-crown-5 group, 18-crown-6 group or 12-crown-4 group.

5. The packaging material according to claim 4, characterized in that: In formula (1), R1 and R2 are independently selected from methyl, ethyl, propyl, carbomethoxy, carboethoxy, methoxy or trimethoxysilylpropyl.

6. The packaging material according to claim 1, characterized in that: The thickness of the coating is d, wherein d satisfies: 25um≤d≤75um.

7. The packaging material according to any one of claims 1 to 6, characterized in that: The substrate comprises an aluminum-plastic film.

8. A method for preparing a packaging material according to any one of claims 1 to 7, characterized in that: The following steps are involved: The solution of the compound having an epoxypropyl group is disposed on one surface of the substrate in the thickness direction, and dried and solidified to form the packaging material having the coating layer.

9. The method for preparing a packaging material according to claim 8, characterized in that: The preparation method of the compound having an epoxypropyl group is as follows: The compound having the glycidyl group is obtained by polymerizing glycidyl methacrylate with an ethylenic monomer.

10. The method for preparing a packaging material according to claim 8, characterized in that: The preparation of the solution of the compound having an epoxypropyl group comprises the following steps: A dispersant and the compound having a glycidyl group are mixed to obtain a solution of the compound having a glycidyl group.

11. The method for preparing a packaging material according to claim 10, characterized in that: The mixing of the dispersant and the compound having an epoxypropyl group specifically comprises: The dispersant is dissolved in a first solvent to obtain a first solution, and the first solution and the compound having a glycidyl group are mixed.

12. The method for preparing a packaging material according to claim 11, characterized in that: The step of dissolving the dispersant in the first solvent to obtain the first solution specifically includes: The dispersant is dissolved in the first solvent, and a catalyst is added to obtain the first solution.

13. The method for preparing a packaging material according to claim 12, characterized in that: The mass ratio of the dispersant, the first solvent and the catalyst is (10-20): (80-200): (5-10).

14. The method for preparing a packaging material according to claim 12, characterized in that: The catalyst includes azobisisobutyronitrile and / or an alkali metal salt.

15. The method for preparing a packaging material according to claim 14, characterized in that: The alkali metal salt includes at least one of LiBr, LiCl, LiI, KBr and KCl.

16. The method for preparing a packaging material according to claim 10, characterized in that: The mixing temperature is 60° C. to 80° C., and the mixing time is 8 h to 24 h.

17. The method for preparing a packaging material according to claim 11, characterized in that: The first solvent includes at least one of ethanol, methanol, ether and toluene.

18. The method for preparing a packaging material according to any one of claims 9 to 17, characterized in that: The polymerizing reaction of glycidyl methacrylate and vinyl monomer includes mixing the glycidyl methacrylate, the vinyl monomer and a second solvent to carry out the polymerization reaction.

19. The method for preparing a packaging material according to claim 18, characterized in that: The second solvent includes at least one of N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide and tetrahydrofuran.

20. The method for preparing a packaging material according to any one of claims 9 to 17, characterized in that: The polymerization reaction temperature is 60° C. to 80° C., and the polymerization reaction time is 8 h to 24 h.

21. The method for preparing a packaging material according to any one of claims 9 to 17, characterized in that: The vinyl monomer includes at least one of methyl acrylate, ethyl acrylate, methyl methacrylate, butyl acrylate, styrene, 3-(trimethoxysilyl)propyl methacrylate and N-vinyl pyrrolidone.

22. A battery, characterized in that: The invention comprises a packaging material according to any one of claims 1 to 7, or a packaging material prepared by the method for preparing a packaging material according to any one of claims 8 to 21.

23. An electrical equipment, characterized in that: Comprising a battery according to claim 22.

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