Aqueous coating composition, aqueous electrode plate, and aqueous battery

Abstract

This application provides an aqueous coating composition, an aqueous electrode plate, and an aqueous battery, wherein the aqueous coating composition comprises an aqueous adhesive and a solvent, the aqueous adhesive comprises a first polymer, the first polymer comprises a structural unit shown in formula (1) and a structural unit shown in formula (2), in formula (1), R1, R2, and R3 are each independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and L is a linkage bond or a C1-10 alkylene group, and in formula (2), R4, R5, and R6 are each independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and n=2-12.

Description

[Technical Field]

[0001] (Mutual citation of related applications) This application is proposed based on a Chinese patent application with application number 202311021430.7 and filing date 14 August 2023, claiming priority from said Chinese patent application, and all contents of said Chinese patent application are incorporated into this application by reference.

[0002] This application relates to the battery technology field, and more particularly to aqueous coating compositions, aqueous electrodes, and aqueous batteries. [Background technology]

[0003] In recent years, as the range of applications for rechargeable batteries has expanded, they are widely used in energy storage and power systems such as hydroelectric, thermal, wind, and solar power plants, as well as in many fields such as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, and aerospace. Because rechargeable batteries have undergone such significant development, higher performance demands are now being placed on them.

[0004] Currently, water-based batteries are attracting widespread attention due to their environmentally friendly and pollution-free properties. However, because of the high water resistance requirements for the water-based electrode plates, how to provide superior water resistance to these plates and improve the safety and cycle life of water-based batteries is an urgent issue that needs to be resolved in this field. [Overview of the project] [Means for solving the problem]

[0005] This application has been made in view of the above-mentioned problems, and its purpose is to provide a water-based coating composition, a water-based electrode plate, and a water-based battery that improve the adhesive strength and water resistance of water-based electrode plates, reduce the risk of water-based coating peeling off, and further improve the safety performance and cycle performance of water-based batteries.

[0006] To achieve the above object, a first aspect of the present application provides an aqueous coating composition, which is characterized in that the composition contains an aqueous adhesive and a solvent, the aqueous adhesive contains a first polymer, and the first polymer contains a structural unit represented by formula (1) and a structural unit represented by formula (2).

[0007]

Chemical formula

[0008] In formula (1), R1, R2, and R3 are each independently hydrogen, halogen, an alkyl group, a hydroxyalkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an alkynyl group, a heterocycloalkyl group, an aryl group, a heteroaryl group, a hydroxy group, a cyano group, or a nitro group, and L is a linking bond or a C1-10 alkylene group.

[0009]

Chemical formula

[0010] In formula (2), R4, R5, and R6 are each independently hydrogen, halogen, an alkyl group, a hydroxyalkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an alkynyl group, a heterocycloalkyl group, an aryl group, a heteroaryl group, a hydroxy group, a cyano group, or a nitro group, and n = 2-12.

[0011] In the aqueous coating composition of the present application, the carboxyl group in the structural unit represented by formula (1) and the hydroxy group in the structural unit represented by formula (2) can form a hydrogen bond and / or a crosslinked structure, thereby improving the adhesion force in the aqueous electrode plate, providing excellent water resistance to the aqueous electrode plate, reducing the risk of film peeling, and improving the safety and cycle performance of the battery.

[0012] In any embodiment, in formula (1), R1, R2, and R3 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and L is a linkage bond or a C3-4 alkylene group; in formula (2), R4, R5, and R6 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and n=3-6. By incorporating the above functional groups into the structural units shown in formulas (1) and (2), the adhesion between the aqueous coating and the current collector can be improved, and as the battery usage time is extended, the improved adhesion is advantageous in further improving cycle performance.

[0013] In any embodiment, in the first polymer, the mass occupancy of the structural unit shown in formula (1) is 10% to 75%, and the mass occupancy of the structural unit shown in formula (2) is 5% to 40%. By keeping the content of each structural unit within the above ranges, a high-density crosslinked network structure can be formed.

[0014] In any embodiment, the first polymer further comprises the structural units shown in formula (3) and / or formula (4),

[0015] [ka] In formula (3), R7, R8, and R9 are each independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group. R 10 It is a rigid group, optionally a cyano group, an amide group, or an aryl group, optionally a cyano group,

[0016] [ka]

[0017] In equation (4), R 11 , R 12 , R 13 Each of these is independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group, and m = 2 to 12.

[0018] The structural unit shown in formula (3) can provide strength to the material in the hard segment, and the structural unit shown in formula (4) can provide flexibility to the material in the soft segment, which improves the penetration and spreading of water-based coatings onto substrates, especially oil-containing substrates (e.g., oil-containing aluminum foil), and is advantageous for improving adhesion and water resistance.

[0019] In any embodiment, the mass occupancy of the structural unit shown in formula (3) in the first polymer is 5% to 40%. In any embodiment, the mass occupancy of the structural unit shown in formula (4) in the first polymer is 10% to 75%. This allows the water-based coating to have appropriate hardness and flexibility, which is advantageous in improving the adhesion and water resistance of the water-based coating.

[0020] In any embodiment, in the first polymer, the mass occupancy of the structural unit shown in formula (1) is 30% to 55%, the mass occupancy of the structural unit shown in formula (2) is 5% to 15%, the mass occupancy of the structural unit shown in formula (3) is 10% to 20%, and the mass occupancy of the structural unit shown in formula (4) is 30% to 55%. By keeping the content of each structural unit within the above ranges, it is advantageous to improve adhesive strength and water resistance.

[0021] In any embodiment, the number-average molecular weight of the first polymer is 200,000 to 1,000,000, and optionally 300,000 to 600,000. By setting the number-average molecular weight within this range, some entanglement can be generated in the adhesive molecular chains inside the aqueous coating, which is advantageous for the formation of a three-dimensional network structure in the aqueous coating, improving adhesive strength. Furthermore, by setting the number-average molecular weight within this range, the entanglement can be controlled to an appropriate range, thereby obtaining excellent flexibility.

[0022] In any embodiment, the aqueous adhesive further comprises a second polymer, which is different from the first polymer and contains groups that are reactive with the first polymer, and which can form hydrogen bonds and / or crosslinked structures with the first polymer. By further comprising the second polymer and forming hydrogen bonds and / or crosslinked structures with the first polymer, a high-density three-dimensional network crosslinked structure can be formed, further improving adhesion and enhancing the water resistance of the aqueous coating.

[0023] In any embodiment, the second polymer contains a flexible group, which is a group containing an ester bond or a group containing an ether bond. By including a flexible group in the polymer, the flexibility of the adhesive can be improved, the brittleness of the coating can be improved, and it is advantageous for improving the water resistance of water-based coatings.

[0024] In any embodiment, the second polymer includes the structural unit shown in formula (5), the structural unit shown in formula (6), and the structural unit shown in formula (7).

[0025] [ka]

[0026] In formula (5), R’1, R’2, and R’3 are the same as or different from R1, R2, and R3, respectively, and are each independently hydrogen, halogen, an alkyl group, a hydroxyalkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an alkynyl group, a heterocycloalkyl group, an aryl group, a heteroaryl group, a hydroxy group, a cyano group, or a nitro group, and L’ is the same as or different from L and is a linking bond or a C1-10 alkylene group.

[0027]

Chemical formula

[0028] In formula (6), R’4, R’5, and R’6 are the same as or different from R4, R5, and R6, respectively, and are each independently hydrogen, halogen, an alkyl group, a hydroxyalkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an alkynyl group, a heterocycloalkyl group, an aryl group, a heteroaryl group, a hydroxy group, a cyano group, or a nitro group, and n’ is the same as or different from n and n’ = 2 - 12.

[0029]

Chemical formula

[0030] In formula (7), R’ 11 , R’ 12 , R’ 13 are the same as or different from R 11 , R 12 , R 13 respectively, and are each independently hydrogen, halogen, an alkyl group, a hydroxyalkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an alkynyl group, a heterocycloalkyl group, an aryl group, a heteroaryl group, a hydroxy group, a cyano group, or a nitro group, and m’ is the same as or different from m and m’ = 2 - 12.

[0031] The carboxyl group of the structural unit shown in formula (5) and / or the hydroxyl group of the structural unit shown in formula (6) in the second polymer above forms hydrogen bonds and / or crosslinked structures with the carboxyl group of the structural unit shown in formula (1) and / or the hydroxyl group of the structural unit shown in formula (2) in the first polymer above, forming a high-density three-dimensional network crosslinked structure, which is advantageous for improving the adhesion and water resistance of water-based coatings.

[0032] In any embodiment, in formula (5), R'1, R'2, and R'3 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and L' is a linkage bond or a C3-4 alkylene group, in formula (6), R'4, R'5, and R'6 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and n'=3-6, in formula (7), R' 11 , R' 12 , R' 13 Each of these is independently a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxy group, a hydroxyl group, or a cyano group, with m' = 3 to 6. Optimizing the structure of the structural units is advantageous for forming a high-density three-dimensional network system, which is advantageous for improving adhesion and water resistance.

[0033] In any embodiment, in the second polymer, the mass occupancy of the structural unit shown in formula (5) is 10% to 60%, the mass occupancy of the structural unit shown in formula (6) is 5% to 20%, and the mass occupancy of the structural unit shown in formula (7) is 20% to 60%. By setting the content of each structural unit within the above ranges, it is advantageous to form a high-density three-dimensional network crosslinking system, which is advantageous for further improving adhesive strength and water resistance.

[0034] In any embodiment, the number-average molecular weight of the second polymer is 200,000 to 1,200,000, and optionally 250,000 to 600,000. By setting the number-average molecular weight within this range, some entanglement can be generated in the adhesive molecular chains inside the aqueous coating, which is advantageous for the formation of a three-dimensional network structure in the aqueous coating, improving adhesive strength. Furthermore, by setting the number-average molecular weight within this range, the entanglement can be controlled to an appropriate range, thereby obtaining excellent flexibility.

[0035] In any embodiment, the structural unit of formula (2) and the structural unit of formula (6) are both

[0036] [ka] By making the above structural unit a specific structure, the adhesive strength of the adhesive on the water-based electrode plate is significantly improved, and the water resistance of the water-based electrode plate is enhanced.

[0037] In any embodiment, the mass ratio of the first polymer to the second polymer is 9:1 to 1:9, and optionally 4:1 to 1:4. By setting the mass ratio of the first polymer to the second polymer within the above range, hydrogen bonds can be formed at high density, which is advantageous for forming a high-density three-dimensional network system and further improving water resistance.

[0038] In any embodiment, the solvent is water. Using water as a solvent is cost-effective, environmentally friendly, and pollution-free. In any embodiment, the composition further comprises an insulating material and / or a dispersant, optionally the insulating material being a ceramic material, optionally the ceramic material being boehmite powder, and optionally the dispersant being a polyacrylamide-based dispersant. This is advantageous for improving insulation and enhancing the safety performance of the battery.

[0039] A second aspect of this application further provides a water-based electrode plate comprising a water-based coating, the water-based coating being formed from the water-based coating composition of the first aspect of this application and having a three-dimensional network crosslinking structure. By incorporating a three-dimensional network crosslinking structure into the water-based coating, the adhesive strength and water resistance of the water-based coating are increased, improving the battery's cycle performance and safety performance.

[0040] In any embodiment, the water-based coating contains 10% to 30% by mass, optionally 15% to 25% by mass, of the total mass of the water-based coating, of an aqueous adhesive. By setting the adhesive content within the above range, the adhesive strength of the water-based coating can be improved, water resistance can be enhanced, and the insulating material content can be increased, thereby improving the insulating effect.

[0041] In any embodiment, the aqueous coating contains 65% to 80% by mass of insulating material and 0.2% to 1.0% by mass of dispersant relative to the total mass of the aqueous coating. This is advantageous for improving insulation and improving the safety performance of the battery.

[0042] In any embodiment, the contact angle between the aqueous coating and water is 90° or less, and optionally between 40° and 80°. This allows for high penetration of the aqueous coating on the aqueous electrode plate, enabling the coating to spread more sufficiently on the substrate, increasing the contact area, improving the adhesion of the aqueous coating to the substrate surface, and reducing the risk of detachment.

[0043] In any embodiment, the peel strength of the aqueous coating on the aqueous electrode plate is 10 N / m or more, optionally 17 N / m or more, and the peel strength is obtained by performing a peel test in accordance with the national standard GB / T 41511-2022.

[0044] In any embodiment, the aqueous electrode plate is either an aqueous positive electrode plate or an aqueous negative electrode plate.

[0045] A third aspect of this application further provides an aqueous battery including an aqueous electrode plate according to the second aspect of this application. As a result, the aqueous battery of this application has excellent safety performance and cycle performance.

[0046] A fourth aspect of this application further provides a power consumption device including an aqueous battery according to the third aspect of this application.

[0047] Effects of the invention The aqueous coating composition of this application contains a polymer of a specific structure as an aqueous adhesive, thereby forming a three-dimensional network crosslinked structure in the aqueous coating, improving the adhesion strength of the aqueous coating on the electrode plate, and further improving the water resistance of the coating. In addition, the polymer contains flexible structural units having an ester structure, which can improve the flexibility of the coating and further contribute to improving the water resistance of the coating. The aqueous electrode plate of this application contains a coating with high adhesion strength and high water resistance, thereby realizing the application of aqueous electrode plate technology and improving the safety performance and cycle performance of aqueous batteries. [Brief explanation of the drawing]

[0048] [Figure 1] This is a schematic partial cross-sectional view of an electrode plate according to several embodiments of this application. [Figure 2] These are infrared spectra obtained by infrared testing of the first polymers 1-20 obtained in the manufacturing example of this application. [Figure 3] This is the infrared spectrum obtained by infrared testing the aqueous coating on the positive electrode plate after disassembling the battery manufactured in Example 24 of this application. [Explanation of Symbols]

[0049] 1-Current collector, 11-Conductive layer, 12-Insulating layer, 13-Base material, 2-Active material layer. [Modes for carrying out the invention]

[0050] Embodiments of the aqueous coating composition, aqueous electrode plate, aqueous battery, and power consumption device of this application will be described in detail below. However, unnecessary detailed explanations may be omitted. For example, detailed explanations of well-known matters and redundant explanations of structures that are actually the same may be omitted. This is to avoid making the following explanation unnecessarily long and to make it easily understandable to those skilled in the art. The drawings and the following explanation are provided to enable those skilled in the art to fully understand this application and do not limit the topics described in the claims.

[0051] The “range” disclosed in this application is limited in the form of a lower limit and an upper limit, and a given range is limited by selecting one lower limit and one upper limit, which define the boundary of a particular range. The range thus limited may or may not include the endpoints, and any combination is possible, that is, any lower limit can be combined with any upper limit to form a range. For example, if the ranges 60-120 and 80-110 are listed for a particular parameter, it is understood that the ranges 60-110 and 80-120 can also be assumed. Furthermore, if 1 and 2 are listed as the minimum range values ​​and 3, 4, and 5 are listed as the maximum range values, then the ranges 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5 can all be assumed. In this application, unless otherwise specified, the numerical range “a-b” represents an abbreviated expression for any combination of real numbers a-b, where a and b are both real numbers. For example, the numerical range "0 to 5" indicates that all real numbers between "0 to 5" have already been listed in this specification, and "0 to 5" is simply an abbreviated representation of combinations of these numbers. Also, when a parameter is described as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0052] Unless otherwise stated, the following terms used in the specification and claims have the meanings set forth below.

[0053] "Halogen" refers to fluorine, chlorine, bromine, or iodine, and is optionally fluorine or chlorine.

[0054] "Alkyl group" refers to a saturated aliphatic hydrocarbon group, which is a linear or branched group containing 1 to 20 carbon atoms. Optionally, moderate alkyl groups containing 1 to 10 carbon atoms include, for example, methyl, ethyl, propyl, 2-propyl, n-butyl, isobutyl, tert-butyl, and pentyl groups. Furthermore, optionally, lower alkyl groups containing 1 to 4 carbon atoms include, for example, methyl, ethyl, propyl, 2-propyl, n-butyl, isobutyl, or tert-butyl groups. Alkyl groups may be substituted or unsubstituted, and if substituted, the group can optionally be a halogen, hydroxyl, lower alkoxy, aryl, aryloxy, heteroaryl, or heterocycloalkyl group.

[0055] A "hydroxyalkyl group" refers to a group formed by substituting a hydrogen atom in the alkyl group described above with a hydroxyl group.

[0056] A "cycloalkyl group" refers to a monocyclic or polycyclic fused ring of 3 to 8 members, 5 / 6 or 6 / 6 members, or a group of 3 to 8 members of carbon atoms (a "fused ring" is one in which each ring in the system shares one pair of adjacent carbon atoms with the other rings in the system), where one or more rings may contain one or more double bonds, but none of the rings have a complete conjugated π-electron system. Examples of cycloalkyl groups include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclopentene, cyclohexane, cyclohexadiene, adamantane, cycloheptane, and cycloheptatriene. Cycloalkyl groups may be substituted or unsubstituted. If substituted, there may be one or more substituents, which are independently selected from lower alkyl groups, trihaloalkyl groups, halogens, hydroxyl groups, lower alkoxy groups, aryl groups, aryloxy groups, 6-membered heteroaryl groups, 5-membered heteroaryl groups, or 5 or 6-membered heterocycloalkyl groups, mercapto groups, (lower alkyl)thio groups, cyano groups, nitro groups, carboxyl groups, and ester groups.

[0057] The term "alkoxy group" refers to -O- (alkyl group) and -O- (unsubstituted cycloalkyl group). The definitions of alkyl groups and cycloalkyl groups are the same as above. Typical examples include, but are not limited to, methoxy, ethoxy, propoxy, butoxy, cyclopropoxy, cyclobutoxy, cyclopentyloxy, and cyclohexyloxy groups.

[0058] An "alkenyl group" refers to an alkyl group as defined above, consisting of at least two carbon atoms and at least one carbon-carbon double bond. Typical examples include, but are not limited to, vinyl groups, 1-propenyl groups, 2-propenyl groups, and 1-, 2-, or 3-butenyl groups.

[0059] An "alkynyl group" refers to an alkyl group as defined above, consisting of at least two carbon atoms and at least one carbon-carbon triple bond. Typical examples include, but are not limited to, ethynyl, 1-propynyl, 2-propynyl, and 1-, 2-, or 3-butynyl groups.

[0060] A "heterocycloalkyl group" refers to a monocyclic or fused ring group, where the ring has 5 to 9 ring atoms, one or two of which are selected from nitrogen, oxygen, or sulfur, and the remaining ring atoms are carbon. These rings may further contain one or more double bonds, but these rings do not have a complete conjugated π-electron system. Unsubstituted heterocycloalkyl groups include, but are not limited to, pyrrolidinyl, piperidino, morpholinyl, thiomorpholinyl, and homopiperazine groups, and heterocycloalkyl groups may be substituted or unsubstituted. If substituted, the substituents are optionally substituted with one or more substituents preferably selected from halogens, trihalomethyl groups, hydroxyl groups, nitro groups, cyano groups, alkoxy groups, alkyl groups, carboxyl groups, and ester groups.

[0061] An "aryl group" refers to a group having at least one aromatic ring structure, i.e., an aromatic ring having a conjugated π-electron system, and includes carbocyclic aryl groups, heteroaryl groups, and biaryl groups. The aryl group may be optionally substituted with one or more substituents selected from halogens, trihalomethyl groups, hydroxyl groups, nitro groups, cyano groups, alkoxy groups, alkyl groups, carboxyl groups, and ester groups.

[0062] A "heteroaryl group" refers to an aryl group in which 1 to 3 heteroatoms form a ring atom and the remaining ring atom is carbon, and the heteroatoms include oxygen, sulfur, and nitrogen. The ring may be a 5-membered or 6-membered ring. Examples of heterocyclic aryl groups include furyl, thienyl, pyridyl, pyrrolyl, N-alkylpyrrolyl, pyrimidinyl, pyrazinyl, and imidazolyl groups. The heteroaryl group may be optionally substituted with one or more substituents selected from halogens, trihalomethyl groups, hydroxyl groups, nitro groups, cyano groups, alkoxy groups, alkyl groups, carboxylic acid groups, and ester groups.

[0063] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical inventions.

[0064] Unless otherwise specified, all technical features and optional technical features of this application can be combined to form new technical concepts.

[0065] Currently, battery electrode plates are transitioning to environmentally friendly and pollution-free water-based electrode plate systems. However, conventional insulating coating formulations are not suitable for water-based electrode plate systems. This is because most conventional insulating coating formulations are oil-based, meaning they use N-methylpyrrolidone (NMP) as a solvent, and the adhesives used are mainly those that dissolve in NMP, such as polyvinylidene fluoride (PVDF) and polyimide. Since NMP is a petroleum-derived chemical product, its synthesis and post-processing processes are complex. Furthermore, when manufacturing electrode plates, large amounts of NMP toxic gases volatilize into the air, polluting the environment and posing a risk to human health. This contradicts one of the main objectives of water-based electrode plate systems: environmental protection. Furthermore, the oil-based formulation system of the insulating coating described above is incompatible with water-based electrode plates. The water used as a solvent in the water-based electrode plate system has a different drying efficiency than the NMP solvent used in conventional insulating coating formulation systems. This leads to poor drying of the electrode plate coating, causing the film layer area to dry out too much during sustained heating, making it prone to cracking and ultimately detachment.

[0066] Therefore, current aqueous electrode plates urgently require an aqueous insulating coating, which not only needs to have excellent adhesive strength to be suitable for aqueous battery applications, but also needs to be water-resistant.

[0067] Based on this, this application provides an aqueous coating composition suitable for aqueous electrode plates, comprising an aqueous adhesive and a solvent. The aqueous adhesive comprises a first polymer.

[0068] First polymer The first polymer comprises the structural unit shown in formula (1) and the structural unit shown in formula (2).

[0069] [ka]

[0070] In formula (1), R1, R2, and R3 are each independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group, and L is a linkage bond or a C1-10 alkylene group.

[0071] A C1-10 alkylene group refers to an alkylene group having 1 to 10 carbon atoms, and may include, but is not limited to, methylene, ethylidene, propylidene, butylidene, pentylidene, hexylidene, heptylidene, octadiene, nonadiene, and desylidene groups.

[0072] [ka]

[0073] In formula (2), R4, R5, and R6 are each independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group, and n = 2 to 12.

[0074] The water-based adhesive in this application has a special crosslinkable structure and comprises a certain number of ester-based structures shown in formula (2). By changing the molecular chain of the adhesive from linear to a more robust three-dimensional network structure, the water resistance of the water-based coating is improved. Furthermore, the ester-based structures shown in formula (2) act as lipophilic groups, allowing the water-based coating to penetrate and spread more effectively onto the substrate (such as aluminum foil), resulting in a higher adhesive effect. This provides the water-based film layer with high adhesive strength and high water resistance, improving the safety and cycle life of the battery.

[0075] In some embodiments, in formula (1), R1, R2, and R3 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and L is a linkage bond or a C3-4 alkylene group; in formula (2), R4, R5, and R6 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and n = 3 to 6, for example, 3, 4, 5, and 6. By providing the above functional groups to the above structural units, the adhesion between the coating and the current collector can be further improved, and as the battery usage time is extended, the improved adhesion is advantageous in further improving the battery's cycle performance.

[0076] In some embodiments, in the first polymer described above, the mass occupancy of the structural units shown in formula (1) is 10% to 75%, and the value may be the value at both ends or any value between the two ends, for example, 10%, 20%, 30%, 40%, 50%, 60%, 70%, or 75%, but is not limited to these. The mass occupancy of the structural units shown in formula (2) is 5% to 40%, and the value may be the value at both ends or any value between the two ends, for example, 5%, 10%, 20%, 25%, 30%, or 40%, but is not limited to these. By setting the mass occupancy of the structural units within the above ranges, a high-density crosslinked structure can be formed, which is advantageous for improving the water resistance of water-based coatings.

[0077] In some embodiments, the first polymer further comprises the structural unit shown in formula (3) and / or the structural unit shown in formula (4),

[0078] [ka]

[0079] In formula (3), R7, R8, and R9 are each independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group. R 10 It is a rigid group, optionally a cyano group, an amide group, or an aryl group, and optionally a cyano group.

[0080] [ka]

[0081] In equation (4), R 11 , R 12 , R 13Each of these is independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group, and m = 2 to 12.

[0082] The structural unit shown in formula (3) can provide strength to the material in the hard segment, and the structural unit shown in formula (4) can provide flexibility to the material in the soft segment, which is advantageous in improving the penetration and spreading of the coating onto the substrate, especially oil-containing substrates (e.g., oil-containing aluminum foil), thereby improving adhesion and water resistance.

[0083] In some embodiments, the mass occupancy of the structural units shown in formula (3) in the first polymer is 5% to 40%. The value may be the value at both ends, or any value between the two ends, for example, 10%, 20%, 30%, or 40%, but is not limited to these. By setting the structural unit content within the above range, it is advantageous to provide the water-based coating with appropriate hardness and to improve adhesive strength.

[0084] In some embodiments, the mass occupancy of the structural units shown in formula (4) in the first polymer is 10% to 75%. The value may be the value at both ends, or any value between the two ends, for example, 10%, 15%, 20%, 30%, 40%, 50%, 60%, or 70%, but is not limited to these. By setting the structural unit content within the above range, it is advantageous to provide the water-based coating with appropriate flexibility and to improve water resistance.

[0085] In some embodiments, in the first polymer described above, the mass occupancy of the structural unit shown in formula (1) is 30% to 55%, the mass occupancy of the structural unit shown in formula (2) is 5% to 15%, the mass occupancy of the structural unit shown in formula (3) is 10% to 20%, and the mass occupancy of the structural unit shown in formula (4) is 30% to 55%. By keeping the content of each structural unit within the above ranges, it is advantageous for forming a three-dimensional network crosslinked structure, improving the adhesion strength of the water-based coating and enhancing water resistance.

[0086] In some embodiments, the linkages on both sides of each structural unit in the first polymer are connected to each other to form a polymer chain as shown below, but the method of connection of each structural unit in the first polymer is not limited thereto.

[0087] [ka]

[0088] a and d are both arbitrary integers > 0, and b and c are both arbitrary integers ≥ 0. The values ​​of a, b, c, and d may be the same or different.

[0089] In some embodiments, the number-average molecular weight of the first polymer is 200,000 to 1,000,000, and optionally 300,000 to 600,000. By setting the number-average molecular weight within this range, some entanglement can be generated in the adhesive molecular chains inside the aqueous coating, which is advantageous for the formation of a three-dimensional network structure in the aqueous coating and improves adhesive strength. Furthermore, by setting the number-average molecular weight within this range, the entanglement can be controlled to an appropriate range, thereby obtaining excellent flexibility and improving the water resistance of the aqueous coating.

[0090] Second polymer In some embodiments, the aqueous adhesive in the aqueous coating composition of this application further comprises a second polymer, which is different from the first polymer and contains groups that can react with the first polymer, and these groups can form hydrogen bonds and / or crosslinked structures with the first polymer. By further comprising the second polymer and forming hydrogen bonds and / or crosslinked structures with the first polymer, a high-density three-dimensional network crosslinked structure can be formed, further improving adhesion and further improving the water resistance of the aqueous coating. "The second polymer is different from the first polymer" includes situations in which each structural unit of the second copolymer is different from the first copolymer, where each structural unit of the second copolymer is the same as the first copolymer but the connection method of each structural unit is different, and where each structural unit of the second copolymer is the same as the first copolymer but the mass occupancy of each structural unit is different.

[0091] In some embodiments, the second polymer includes a flexible group, which is a group containing an ester bond or an ether bond. The flexible group includes, but is not limited to, a methyl acrylate group, an ethyl acrylate group, a propyl acrylate group, a methoxy group, an ethoxy group, and the like. These groups can improve the flexibility of the coating, effectively reduce the risk of tab folding, improve the water resistance of the coating, and enhance the safety performance of the battery.

[0092] In some embodiments, the second polymer includes the structural unit shown in formula (5), the structural unit shown in formula (6), and the structural unit shown in formula (7).

[0093] [ka]

[0094] In formula (5), R'1, R'2, and R'3 are either the same as or different from R1, R2, and R3, respectively, and are independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and L' is either the same as or different from L, and is a linkage or a C1-10 alkylene group. The definition of "C1-10 alkylene group" is the same as the definition in the first polymer.

[0095] [ka]

[0096] In formula (6), R'4, R'5, and R'6 are either the same as or different from R4, R5, and R6, respectively, and are independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and n' is either the same as or different from n, with n' = 2 to 12.

[0097] [ka]

[0098] In equation (7), R' 11 , R' 12 , R' 13 R 11 , R 12 , R 13 m' is either the same as or different from m, and each is independently a hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group, and m' is either the same as or different from m, with m' = 2 to 12.

[0099] This application describes a method using a mixture of two polymers, in which the carboxyl groups of the structural units shown in formula (1) and / or the hydroxyl groups of the structural units shown in formula (2) in the first polymer interact with the carboxyl groups of the structural units shown in formula (5) and / or the hydroxyl groups of the structural units shown in formula (6) in the second polymer to form hydrogen bonds, or may be further reacted through treatment such as heating to form new chemical bonds, such as ester bonds, thereby constructing a high-density three-dimensional network crosslinked structure within the coating, thereby providing sufficient adhesion to the aqueous coating and further improving the water resistance of the water-based coating.

[0100] Furthermore, the structural unit shown in formula (3) in the first polymer, i.e., the acrylonitrile monomer, is a rigid monomer and can provide strength to the material. The structural unit shown in formula (7) in the second polymer, i.e., the acrylate monomer, is a flexible monomer and can provide flexibility to the coating. As lipophilic groups, they can better penetrate and spread water-based coatings onto substrates, especially oil-containing substrates (e.g., oil-containing aluminum foil), which is advantageous in improving water resistance and enhancing battery safety.

[0101] In some embodiments, in formula (5), R'1, R'2, and R'3 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and L' is a linkage bond or a C3-4 alkylene group; in formula (6), R'4, R'5, and R'6 are each independently hydrogen, alkyl group, hydroxyalkyl group, alkoxy group, hydroxy group, or cyano group, and n'=3-6; and in formula (7), R' 11 , R' 12 , R' 13Each of these is independently a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxy group, a hydroxyl group, or a cyano group, with m' = 3 to 6. Furthermore, by providing the above functional groups to the above structural units, the adhesion between the coating and the current collector is further improved, and as the battery usage time is extended, the improved adhesion is advantageous in further improving cycle performance.

[0102] In some embodiments, in the second polymer described above, the mass occupancy of the structural unit shown in formula (5) is 10% to 60%, the mass occupancy of the structural unit shown in formula (6) is 5% to 20%, and the mass occupancy of the structural unit shown in formula (7) is 20% to 60%. By setting the mass occupancy of each structural unit within the above ranges, it is advantageous to form a high-density three-dimensional network system, which is advantageous to further improve adhesive strength and water resistance.

[0103] In some embodiments, the structural unit shown in formula (2) in the first polymer and the structural unit shown in formula (6) in the second polymer are both

[0104] [ka] This is because, by controlling the length of the alkane chain through the hydroxypropyl ester structure, the swelling rate of the adhesive material in the electrolyte can be effectively reduced compared to long-chain structures such as hydroxybutyl esters and hydroxyhexyl esters. This further reduces the possibility of detachment by effectively adhering the coating to the substrate during long-term use. Furthermore, compared to short-chain structures such as hydroxymethyl esters and hydroxyethyl esters, the longer carbon chain makes the coating on the electrode plate more flexible, reducing the risk of bending or breaking of the coating and improving water resistance. Moreover, by matching the structural units shown in formula (2) and formula (6), the intermolecular forces are further strengthened, further improving adhesion and water resistance.

[0105] In some embodiments, the structural units in the second polymer are connected to each other to form a polymer chain as shown below, but the method of connecting the structural units in the second polymer is not limited thereto.

[0106] [ka]

[0107] e and g are both arbitrary integers > 0, and f is an arbitrary integer ≥ 0. The values ​​of e, f, and g may be the same or different.

[0108] In some embodiments, the number-average molecular weight of the second polymer is 200,000 to 1,200,000, and optionally 250,000 to 600,000. By setting the number-average molecular weight within this range, some entanglement can be generated in the adhesive molecular chains inside the aqueous coating, which is advantageous for creating a three-dimensional network structure in the aqueous coating and improving adhesive strength. Furthermore, by setting the number-average molecular weight within this range, the entanglement can be controlled to an appropriate range, thereby obtaining excellent flexibility and improving the water resistance of the aqueous coating.

[0109] In some embodiments, the mass ratio of the first polymer to the second polymer is 9:1 to 1:9, and optionally 4:1 to 1:4. Setting the mass ratio of the first polymer to the second polymer within this range is advantageous for forming a high-density three-dimensional network system and for further improving adhesive strength.

[0110] Water-based coating composition In some embodiments, the aqueous coating composition further includes an insulating material and / or a dispersant in addition to the aqueous adhesive, and optionally the insulating material is a ceramic material. The ceramic material includes, but is not limited to, alumina, boehmite, zirconia, titanium oxide, silicon nitride, boron carbide, etc., and optionally is boehmite powder. The dispersant may be, for example, a polyacrylamide-based dispersant. In the coating, the carboxyl groups of the structural unit shown in formula (1) in the first polymer and the carboxyl groups of the structural unit shown in formula (5) in the second polymer can form hydrogen bonds with the boehmite insulating material, further improving the adhesive strength of the aqueous coating.

[0111] In some embodiments, water, such as deionized water, is used as the solvent. By using water as the solvent, costs can be reduced compared to oil-based electrode plate systems that use NMP as the solvent, and pollution is eliminated, thus protecting the environment.

[0112] The aqueous coating slurry may be prepared using, but is not limited to, the following methods.

[0113] (1) Add the dispersant to the deionized water and stir for 5 min to 30 min under conditions of a dispersion rate of 500 rpm to 2000 rpm to obtain dispersion (1). (2) Add boehmite to the above dispersion (1) and stir for 30 min to 120 min under conditions of dispersion speed 500 rpm to 2000 rpm to obtain dispersion (2). (3) Add the first polymer, which is an adhesive, to the dispersion (2) and stir for 30 min to 120 min under conditions of dispersion speed of 500 rpm to 2000 rpm to obtain dispersion (3), which is an aqueous coating slurry.

[0114] If the water-based adhesive further contains a second copolymer, the following steps are performed. (4) Add the second polymer, which is an adhesive, to the dispersion (3) and stir for 15 min to 60 min under conditions of dispersion speed 200 rpm to 1000 rpm to obtain a coating slurry. Further stir for 20 min to 40 min under conditions of dispersion speed 500 to 800 rpm to obtain an aqueous coating slurry.

[0115] water-based electrode plate This application further provides a water-based electrode plate including a water-based coating, the water-based coating being formed from a water-based coating composition according to the first embodiment of this application, and having a three-dimensional network crosslinking structure. By including a three-dimensional network crosslinking structure in the water-based coating, the water resistance of the water-based coating is increased and the risk of film detachment is reduced.

[0116] In some embodiments, the water-based coating contains 10% to 30% by mass, optionally 15% to 25% by mass, of the total mass of the water-based coating as an aqueous adhesive. By setting the adhesive content within the above range, the adhesive strength and water resistance of the water-based coating can be improved.

[0117] In some embodiments, the aqueous coating contains 65% to 80% by mass, optionally 70% to 80% by mass, of insulating material relative to the total mass of the aqueous coating. The aqueous coating also contains 0.2% to 1.0% by mass, optionally 0.5% to 0.8% by mass, of dispersant relative to the total mass of the aqueous coating. This helps to improve the insulating effect.

[0118] In some embodiments, the contact angle between the aqueous coating and water is 90° or less, and optionally between 40° and 80°. The contact angle (θ) refers to the angle θ between the tangent to the gas-liquid interface at the intersection of the gas, liquid, and solid phases and the solid-liquid boundary line, and is a measure of wettability. When θ < 90°, the solid is hydrophilic, meaning the liquid can wet the solid, and the smaller the angle, the higher the wettability. When θ > 90°, the solid is liquor-repellent, meaning the liquid cannot wet the solid, moves easily on the surface, and cannot enter the capillaries.

[0119] This application is advantageous in that by setting the contact angle between the aqueous coating and water within the above range, the wetting properties of the aqueous coating on the aqueous electrode plate are high, the coating spreads more sufficiently on the substrate, the contact area increases, the adhesion strength of the aqueous coating to the substrate surface is improved, the water resistance of the aqueous coating is improved, and the risk of detachment is reduced.

[0120] In some embodiments, the peel strength of the aqueous coating on the aqueous electrode plate is 10 N / m or more, and optionally 17 N / m or more. The peel strength may be obtained by performing a peel test in reference to the national standard GB / T 41511-2022.

[0121] In some embodiments, the aqueous electrode plate is either an aqueous positive electrode plate or an aqueous negative electrode plate.

[0122] The aqueous coating composition of this application can form an insulating coating on an aqueous positive electrode plate. A method for manufacturing the electrode plate will be described exemplified below with reference to Figure 1.

[0123] In the manufacture of the aqueous positive electrode of a battery, an aqueous coating slurry may be prepared using an insulating material, an aqueous adhesive, a dispersant, and deionized water by referring to the above method. The insulating coating slurry and the conductive layer slurry are then applied to at least one surface of a substrate 13 (aluminum foil) and dried to form an insulating coating 12 and a conductive layer 11 on the substrate 13 to obtain a composite positive electrode current collector 1. Then, a slurry containing an active material is applied to the conductive layer 11 to form an active material layer 2, thereby manufacturing an electrode plate.

[0124] During the drying of the electrode plate, under the influence of heat, the carboxyl / hydroxyl groups in the water-based adhesive act to form hydrogen bonds and / or crosslinked structures, creating a three-dimensional network-like crosslinked structure. As a result, the resulting water-based electrode plate has excellent adhesive strength, high water resistance, significantly reduces the occurrence of film detachment, and improves the safety performance of the battery.

[0125] The thickness of a single layer of insulating coating formed from a water-based coating slurry is 1 μm to 20 μm, and optionally 2 μm to 8 μm. A thickness of 1 μm or more provides good insulating protection, while a thickness of 20 μm or less is advantageous for improving battery energy density. The width of the insulating coating is 1 mm to 20 mm, and optionally 3 mm to 10 mm. This provides good insulating protection and is advantageous for improving battery energy density.

[0126] The surface density of the positive electrode film layer of the aqueous positive electrode plate in this application is 250 mg / 1540.25 mm². 2 ~500mg / 1540.25mm 2 Therefore, the coating weight of oil-based electrode plates can be achieved and even exceeded. Furthermore, since the drying temperature of water-based electrode plates is 60°C to 120°C, while the drying temperature of typical oil-based electrode plates is 110°C to 140°C, the application of water-based electrode plates can significantly reduce energy consumption.

[0127] water-based battery One embodiment of this application provides a water-based battery.

[0128] In this specification, “battery” refers to a battery cell, battery module, or battery pack.

[0129] Generally, a battery cell includes a positive electrode plate, a negative electrode plate, an electrolyte, and a separator. During charging and discharging of the battery, active ions are absorbed and released as they move back and forth between the positive and negative electrode plates. The electrolyte acts as a conductor of ions between the positive and negative electrode plates. The separator is placed between the positive and negative electrode plates and primarily serves to prevent short circuits between the positive and negative electrodes, while also allowing ions to pass through.

[0130] [Positive plate] The positive electrode plate includes a positive electrode current collector and a positive electrode film layer provided on at least one surface of the positive electrode current collector, wherein the positive electrode film layer includes the aqueous coating of this application as an insulating coating.

[0131] For example, a positive electrode current collector has two opposing surfaces in its own thickness direction, and the positive electrode film layer is placed on one or both of the two opposing surfaces of the positive electrode current collector.

[0132] In some embodiments, the positive electrode current collector is a composite current collector. The composite current collector may include a base layer and a conductive layer and an insulating layer placed on at least one surface of the base layer.

[0133] In some embodiments, when the battery cell is a lithium-ion battery, the positive electrode active material may be a known positive electrode active material of the art used in lithium-ion batteries. For example, the positive electrode active material may include at least one of olivine-structured lithium-containing phosphates, lithium transition metal oxides, and modified compounds thereof. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may be used. These positive electrode active materials may be used individually or in combination of two or more. Here, examples of lithium transition metal oxides include lithium cobalt oxide (e.g., LiCoO2), lithium nickel oxide (e.g., LiNiO2), lithium manganese oxide (e.g., LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (e.g., LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(NCM 333 (It may also be abbreviated as LiNi) 0.5 Co 0.2 Mn 0.3 O2(NCM 523 (It may also be abbreviated as LiNi) 0.5 Co 0.25 Mn 0.25 O2(NCM 211 (It may also be abbreviated as LiNi) 0.6 Co 0.2 Mn 0.2 O2(NCM 622 (It may also be abbreviated as LiNi) 0.8 Co 0.1 Mn 0.1 O2(NCM 811 (May be abbreviated as LiNi)), Lithium nickel cobalt aluminum oxide (e.g., LiNi 0.85 Co 0.15 Al 0.05The olivine structure lithium-containing phosphate may include, but is not limited to, at least one of the following: O2, and modified compounds thereof. Examples of lithium-containing phosphates with an olivine structure may include, but is not limited to, at least one of the following: lithium iron phosphate (e.g., LiFePO4 (which may be abbreviated as LFP)), composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (e.g., LiMnPO4), composite materials of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon.

[0134] In some embodiments, the positive electrode film layer optionally further comprises an adhesive. For example, the adhesive may include at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), a ternary copolymer of vinylidene fluoride-tetrafluoroethylene-propylene, a ternary copolymer of vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene, a tetrafluoroethylene-hexafluoropropylene polymer, and a fluorine-containing acrylate resin.

[0135] In some embodiments, the cathode film layer optionally further comprises a conductive agent. For example, the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0136] In some embodiments, a positive electrode plate may be manufactured by the following method: The above components for manufacturing an aqueous positive electrode plate, such as a positive electrode active material, a conductive agent, an aqueous adhesive, and any other components, are dispersed in a solvent (e.g., water) to form an aqueous positive electrode slurry. The positive electrode slurry is then applied to a positive electrode current collector, and the positive electrode plate can be obtained through processes such as drying and cold pressing.

[0137] [negative electrode plate] The negative electrode plate includes a negative electrode current collector and a negative electrode film layer placed on at least one surface of the negative electrode current collector, the negative electrode film layer containing a negative electrode active material.

[0138] For example, the negative electrode current collector has two opposing surfaces in its own thickness direction, and the negative electrode film layer is placed on one or both of the two opposing surfaces of the negative electrode current collector.

[0139] In some embodiments, the negative electrode current collector may be a metal foil sheet or a composite current collector. For example, copper foil may be used as the metal foil sheet. The composite current collector includes a base layer and a conductive layer and an insulating layer placed on at least one surface of the base layer.

[0140] In some embodiments, the negative electrode active material may be a known negative electrode active material used in batteries. For example, the negative electrode active material may include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, silicone-based materials, tin-based materials, and lithium titanate. The silicone-based material may be at least one selected from elemental silicone, silicone oxide, silicone-carbon composite, silicone-nitrogen composite, and silicone alloy. The tin-based material may be at least one selected from elemental tin, tin oxide, and tin alloy. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in batteries may be used. These negative electrode active materials may be used individually or in combination of two or more.

[0141] In some embodiments, the negative electrode film layer optionally further comprises an adhesive. The adhesive may be at least one selected from styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0142] In some embodiments, the negative electrode film layer optionally further comprises a conductive agent. The conductive agent may be at least one selected from superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0143] In some embodiments, the negative electrode film layer optionally further comprises other auxiliary agents, such as thickeners (e.g., sodium carboxymethylcellulose (CMC-Na)).

[0144] In some embodiments, the negative electrode plate may be manufactured by the following method: The components for manufacturing the negative electrode plate, such as a negative electrode active material, a conductive agent, an adhesive, and any other components, are dispersed in a solvent (e.g., deionized water) to form a negative electrode slurry; the negative electrode slurry is coated onto a negative electrode current collector; and the negative electrode plate can be obtained through processes such as drying and cold pressing.

[0145] [Electrolyte] The electrolyte plays a role in conducting ions between the positive and negative electrodes. The electrolyte comprises an electrolyte salt and a solvent. This application does not specifically limit the types of electrolyte salt and solvent, and they can be selected according to the needs.

[0146] In some embodiments, the electrolyte salt may be at least one selected from lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, lithium difluorobis(oxalato)phosphate, and lithium tetrafluoro(oxalato)phosphate.

[0147] In some embodiments, the solvent may be at least one selected from ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, ethyl methyl sulfone, and diethyl sulfone.

[0148] In some embodiments, the electrolyte optionally further includes additives. For example, the additives may include a negative electrode film forming additive and a positive electrode film forming additive, and may further include additives that can improve some of the battery's performance, such as an additive that improves the battery's overcharge performance, or an additive that improves the battery's high-temperature or low-temperature performance.

[0149] [Separator] In some embodiments, the aqueous battery further includes a separator. This application is not particularly limited to the type of separator, and any known porous separator having good chemical and mechanical stability may be selected.

[0150] In some embodiments, the material of the separator may be at least one selected from glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multilayer composite film, and is not particularly limited. If the separator is a multilayer composite film, the materials of each layer may be the same or different, and is not particularly limited.

[0151] In some embodiments, the positive electrode plate, negative electrode plate, and separator can be formed into an electrode assembly by a winding process or a lamination process.

[0152] In some embodiments, the battery cell may include an outer casing. This casing may be used to package the electrode assembly and electrolyte.

[0153] In some embodiments, the battery cell casing may be a rigid case, such as a rigid plastic case, an aluminum case, or a steel case. The battery cell casing may also be a pouch, such as a bag-shaped pouch. The pouch material may be plastic, and examples of plastics include polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0154] This application does not particularly limit the shape of the battery cell, which may be cylindrical, rectangular, or any other shape.

[0155] In some embodiments, the battery cells may be assembled into a battery module, and the number of battery cells included in the battery module may be one or more, the specific number of which can be selected by those skilled in the art depending on the application and capacity of the battery module.

[0156] In some embodiments, the battery modules may be further assembled into a battery pack, the number of battery modules included in the battery pack may be one or more, and the specific number can be selected by those skilled in the art based on the application and capacity of the battery pack.

[0157] power consumption equipment Furthermore, this application provides a power consumption device including a battery according to this application. The battery may be used as a power source for the power consumption device, or as an energy storage unit for the power consumption device. The power consumption device may include, but is not limited to, mobile devices (e.g., mobile phones, laptops, etc.), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.

[0158] As the power consumption device, a battery cell, battery module, or battery pack can be selected according to the usage requirements. [Examples]

[0159] Examples The following describes embodiments of this application. The embodiments described below are illustrative and are for interpretive purposes only and should not be understood as limitations thereon. Unless otherwise specified in the embodiments, specific techniques or conditions are carried out in accordance with the techniques, conditions, or product specifications described in the literature in the art. Unless otherwise specified, the reagents or equipment used are all commonly available commercial products.

[0160] Manufacturing example At 20°C, nitrogen gas was introduced into the reaction vessel to remove oxygen, and 4.2 g of the surfactant sodium dodecylbenzenesulfonate was added to 90 g of deionized water and stirred to dissolve uniformly. Then, monomers CH2=CHCOOH of formula (1), CH2=CHCOO(CH2)3OH of formula (2), CH2=CHCN of formula (3), CH2=CHCOO(CH2)3CH3 of formula (4), and 0.05 g of the chain transfer agent n-dodecyl mercaptan were added sequentially and mixed uniformly. After that, the temperature was raised to 85°C and stirred uniformly to obtain a preemulsion.

[0161] Then, 1.5 g of the initiator ammonium persulfate and 2.8 g of the surfactant sodium dodecylbenzenesulfonate were continuously added dropwise to the pre-emulsion. After the addition was complete, the mixture was stirred for 120 minutes at a rotation speed of 300 rpm to obtain a polymer seed solution. Subsequently, another 1.5 g of the initiator ammonium persulfate was added, and the mixture was stirred for another 120 minutes at a rotation speed of 300 rpm to obtain the polymer.

[0162] Next, the polymer was post-treated, the temperature in the reaction vessel was lowered to room temperature, vacuum was applied and maintained for 30 minutes, and then the pressure was returned to atmospheric pressure. Finally, the polymer was filtered through a 300-mesh filter, and the pH was adjusted to 7-8 with lithium hydroxide to obtain the first polymers 1-20, whose compositions are shown in Table 1 below.

[0163] Referring to the method described above, the first and second polymers shown in Tables 1 and 2 below were prepared according to the compositions shown in Tables 1 and 2.

[0164] [Table 1-1] [Table 1-2] In the table, "-" indicates that the ingredient is not included.

[0165] [Table 2]

[0166] Example 1 (1) Preparation of aqueous coating slurry An insulating coating slurry was prepared by adding 91 g of insulating alumina, 2 g of dispersant polyacrylamide (Tohji Chemical, model number 4045N, solids content 50%), and 16 g of the first polymer 1-1 (solids content 50%) as a water-based adhesive to deionized water. The specific procedure is as follows.

[0167] (1-1) Add the dispersant to the deionized water and stir for 30 minutes at a dispersion rate of 1500 rpm to obtain dispersion (1). (1-2) Add alumina to the above dispersion (1) and stir for 60 minutes under conditions of a dispersion speed of 1500 rpm to obtain dispersion (2). (1-3) The first polymer 1-1 as a water-based adhesive was added to the above dispersion (2), and stirred for 90 minutes under conditions of a dispersion speed of 1200 rpm to obtain dispersion (3), which was a water-based coating slurry.

[0168] If the water-based adhesive further contains a second copolymer, the second polymer is added to the dispersion (3) and stirred for 30 minutes under conditions of a dispersion speed of 800 rpm to obtain a water-based coating slurry.

[0169] (2) Manufacturing of current collectors A conductive slurry was prepared using conductive graphite (Shanghai Kaiyin Chemical Co., Ltd., model number SP5000) as a conductive material, xanthan gum (molecular weight approximately 1,000,000 g / mol, Shanghai Alading Biochemical Technology Co., Ltd.) as a dispersant, polyacrylic acid (number average molecular weight 300,000 to 800,000) as an aqueous adhesive, polycarbodiimide (number average molecular weight 10,000 to 40,000) as a curing agent, and water.

[0170] Then, the aqueous coating slurry prepared in (1) above was uniformly applied to one surface of the positive electrode aluminum foil substrate, and applied to the edge region extending 10 mm from the edge to the center of the substrate. The conductive slurry was then uniformly applied to the blank areas of the positive electrode aluminum foil substrate other than the edge region, at a coating speed of 50 to 150 m / min. After that, it was dried at 60°C to 150°C, and during drying and heating, the adhesive in the aqueous coating formed a three-dimensional network crosslinking structure. As a result, a composite positive electrode current collector including an aqueous coating (insulating layer) and a conductive layer was obtained, and the composition of the formed aqueous coating is as shown in Table 3.

[0171] (3) Manufacturing of aqueous positive electrode plates Lithium iron phosphate, the positive electrode active material, conductive carbon black, the conductive agent, polyethylene and pyrrolidone, the dispersion stabilizers, and an acrylate polymer, the aqueous adhesive, were mixed in deionized water as a solvent in a weight ratio of 96:1:1.2:1.8. After uniform mixing, an aqueous positive electrode slurry was obtained with a deionized water content of 40 wt% and a solid content (content of solid components, including the positive electrode active material, conductive agent, dispersion stabilizer, and aqueous adhesive) of 60 wt%. This aqueous positive electrode slurry was then uniformly coated onto the conductive layer of the composite positive electrode current collector manufactured in (2) above, and dried to form an active material layer. Subsequently, a positive electrode plate was obtained by cold pressing and slitting.

[0172] (4) Manufacturing of negative electrode plates The negative electrode active material, artificial graphite, the conductive agent, carbon black, the adhesive, styrene-butadiene rubber (SBR), and the thickener, sodium hydroxymethylcellulose (CMC), were dissolved in deionized water as a solvent in a weight ratio of 96.2:0.8:0.8:1.2 and uniformly mixed to obtain a negative electrode slurry with a deionized water content of 45 wt% and a solid content (containing solid components, including the negative electrode active material, conductive agent, adhesive, and thickener) of 55 wt%. The negative electrode slurry was then uniformly coated onto the copper foil of the negative electrode current collector, and a negative electrode plate was obtained through drying, cold pressing, and slitting.

[0173] (5) Manufacturing of electrolyte In a glove box under an argon atmosphere (H2O < 0.1 ppm, O2 < 0.1 ppm), ethylene carbonate (EC) and ethyl methyl carbonate (EMC) organic solvents were uniformly mixed in a 3 / 7 volume ratio. 12.5% ​​of LiPF6 lithium salt was added and dissolved in the organic solvent, and the mixture was uniformly stirred to obtain an electrolyte.

[0174] (6) Manufacturing of separators A 7μm thick porous PE film was used as the base material, and a 2μm thick ceramic coating was applied to it, forming a composite film that served as the separator.

[0175] (7) Manufacturing of lithium-ion batteries The aqueous positive electrode plate, separator, and negative electrode plate manufactured as described above are stacked in order, with the separator positioned between the positive and negative electrode plates to provide isolation, and then wound up to obtain a battery assembly. The battery assembly is placed in an aluminum case, baked at 80°C to remove water, and then immediately injected with the electrolyte obtained in (5) above and sealed. Subsequently, a lithium-ion battery is obtained through processes such as standing, hot and cold pressing, chemical conversion, shaping, and capacity testing.

[0176] Examples 2-36 The electrode plates were manufactured in the same manner as in Example 1, the composition of the aqueous coating was as shown in Table 3, and the battery was manufactured in the same manner as in Example 1.

[0177] In Table 3, "Content (wt%)" refers to the content of water-based adhesive, insulating material, and dispersant relative to the total mass of the water-based coating. "Boehmite" was purchased from Zhejiang Jizhun New Materials Technology Co., Ltd., with a Dv50 of 1.3 μm.

[0178] [Table 3] In the table, "-" indicates that the ingredient is not included.

[0179] Comparative Example 1 In Example 1 (1), in the preparation of the coating slurry, boehmite (Zhejiang Jizhun New Materials Technology Co., Ltd., Dv50 1.3um) and adhesive PVDF (Suwei Chemical, model number HSV900) were dispersed in the solvent NMP to prepare an insulating coating slurry with an NMP content of 88 wt% and a solid content (including boehmite + adhesive) of 12 wt%. Otherwise, the electrode plates were manufactured in the same manner as in Example 1, and then the battery was manufactured.

[0180] Comparative Example 2 In Example 1 (1), the preparation of the coating slurry was carried out using polyacrylic acid as the adhesive, and otherwise the electrode plates were manufactured in the same manner as in Example 1, and then the battery was manufactured.

[0181] Comparative Example 3 In Example 1 (1), in the preparation of the coating slurry, only polypropylene hydroxyethyl was used as the adhesive, and otherwise the electrode plates were manufactured in the same manner as in Example 1, and then the battery was manufactured.

[0182] The following tests were performed on the positive electrode plate and battery obtained in the above examples and comparative examples.

[0183] Plate coating detection The aqueous coating (insulating layer) of the positive electrode plate in the above example was analyzed according to the infrared spectroscopy method of standard GB / T6040-2002. The specific method is as follows.

[0184] Polymers 1-1 to 1-20 were each used as test samples and analyzed using an IS10 Fourier transform infrared spectrometer manufactured by Nicolet, Inc., USA.

[0185] Furthermore, the batteries obtained in the examples were disassembled to obtain current collectors containing a water-based coating (insulating layer). These were then immersed in diethyl carbonate (DEC), an electrolyte solvent, for 2 hours, and the electrode plates were washed three times with fresh DEC. After drying, these were prepared as test samples. Each of these test samples was then analyzed using an IS10 Fourier transform infrared spectrometer from Nicolet, Inc., USA.

[0186] The infrared spectra of the first polymers 1-1 to 1-20 were compared with those of the examples. The peaks of the carbonyl group and carbon-oxygen single bond in the infrared spectra of the examples all showed a clear redshift, indicating that hydrogen bonds were formed in the aqueous coating of the examples.

[0187] Specifically, Figure 2 shows the infrared spectra obtained by infrared testing of the first polymers 1-20. Figure 3 shows the infrared spectra obtained by infrared testing of the aqueous coating on the positive electrode plate after disassembling the battery manufactured in Example 24. As can be seen from comparing Figure 2 and Figure 3, the peaks of the carbonyl group and carbon-oxygen single bond show a clear redshift (1700, 17 cm⁻¹). -1 →1732.33cm -1 and 1073.69cm -1 →1162.46cm -1 This indicates that hydrogen bonds are formed in the aqueous coating of Example 24, and that a three-dimensional network-like cross-linking structure exists.

[0188] Plate performance test (Electrolyte immersion performance test) The electrode plate to be tested was taken, and its appearance was good. A sample measuring 10 mm wide x 100 mm long was cut with a blade and immersed completely in an electrolyte solvent composed of a composite mixture of EC\DMC\DEC in a 1:1:1 ratio. After immersion at 60°C for 24 hours, it was observed whether or not the coating had peeled off.

[0189] (Peel strength test) Using a tensile testing machine, a 180° peel strength test was performed on the water-based coating in accordance with the national standard GB / T 41511-2022.

[0190] The electrode plate to be tested was taken, and its appearance was good. Electrode plate samples with a width of 10 mm and a length of 100-160 mm were cut with a blade. Special double-sided tape, NITTO.NO5000NS, was applied to the steel plate; the tape width was 10 mm and the length was 90-150 mm. The cut electrode plate samples of the above fixed dimensions were attached to the double-sided tape, with the test surface facing downwards, and then rolled three times with a 3 kg press roller in the same direction as the surface of the positive electrode plate's insulating coating. Paper tape, with the same width as the electrode plate and 80-200 mm longer than the sample, was inserted below the electrode plate and secured with crepe agent. The sample is then fixed on the testing machine, the unattached end of the steel plate is secured with a lower jig, the paper tape is folded upwards and secured with an upper jig, and the axial direction of the electrode plate is held to coincide with the biasing direction. The testing machine applies a load at a peeling speed of 10 mm / min and the test is carried out until the positive electrode plate breaks, the maximum load force F (in N) is recorded, the electrode plate width L = 20 mm and the peel strength f1 (in N / m) is calculated based on f1 = F / L, showing that a higher peel strength indicates higher adhesive strength.

[0191] (Water resistance test) The electrode plate to be tested was taken, and its appearance was good. An electrode plate sample measuring 10 mm in width and 100 mm in length was cut with a blade and completely immersed in a water-containing ultrasonic device. The ultrasonic device model number was BRANSON CPX3800-HC, the ultrasonic frequency was 20 kHz, and the ultrasonic power was 50 W. A stopwatch was started synchronously, and the time it took for the water-based coating to dissolve and detach was recorded.

[0192] (Contact angle test) Referring to the GB / T 30693-2014 standard file, the contact angle between the aqueous coating (insulating layer) and water was tested, using deionized water as the liquid reagent.

[0193] Specifically, the current collector to be tested, containing a water-based coating, was placed flat on the test stage. Then, 0.6 μL to 1.0 μL of deionized water was dispensed using a microsyringe. The test stage was moved by rotating the knob on the base of the test stage until it came into contact with the deionized water droplet. The image was frozen within 10 seconds, and the angle between the tangent to the outer surface of the droplet and the water-based coating plane was measured using an angle measurement method and defined as the contact angle.

[0194] Battery performance test (Battery capacity retention test) The test process for battery capacity retention is as follows: At 25°C, the battery in the example is charged to 3.65V with a constant current of 1 / 3C, then charged again with a constant voltage of 3.65V until the current drops to 0.05C, left for 5 minutes, and then discharged to 2.7V with 1 / 3C. The resulting capacity is recorded as the initial capacity C0. The above steps are repeated for the same battery, and the discharge capacity Cn of the battery after the nth cycle is recorded. In this case, the battery capacity retention rate Pn after each cycle is Cn / C0 * 100%. In this test process, the first cycle corresponds to n=1, the second cycle corresponds to n=2, ... the 100th cycle corresponds to n=100.

[0195] In this application, the battery in the embodiment was subjected to 800 cycles under the above test conditions, and the capacity retention rate was calculated, as shown in Table 4.

[0196] (Battery vibration abuse test) During the winding process of the battery assembly, the water-based coating (insulating coating) portion was folded in half and inserted approximately 2 mm into the innermost part of the battery assembly, bringing it into contact with the active area of ​​the negative electrode plate, and the battery was obtained by operating according to the same method as described in "Manufacturing of Lithium-ion Battery" above.

[0197] The obtained batteries were placed on a vibration table and subjected to 8-hour vibration tests in each of the three directions (X / Y / Z). The battery assemblies were then disassembled to check for burn marks on the plate folds. The presence of burn marks indicates a short circuit inside the battery, resulting in low safety performance. The absence of burn marks indicates high safety performance of the battery.

[0198] The test results for the above examples and comparative examples are shown in Table 4 below.

[0199] [Table 4]

[0200] As shown in the data in Table 4, the aqueous coatings on the positive electrode plates in Examples 1 to 36 of this application exhibit high adhesive strength and high water resistance. Specifically, after immersion of the positive electrode plates in the electrolyte, the aqueous coatings did not detach in any case, and the peel strength of the aqueous coatings was greater than 8 N / m in all cases, indicating high adhesive strength. In water resistance tests, peeling occurred only after a long period of time, demonstrating excellent water solubility. Furthermore, the contact angle between the aqueous coatings and water was less than 90° in all cases, indicating high permeability of the aqueous coatings, which is advantageous for improving the adhesion of the aqueous coatings to the substrate surface. In addition, the aqueous batteries containing the aqueous coatings in Examples 1 to 36 exhibited high capacity retention after 800 cycles, demonstrating excellent battery cycle performance, and none of the batteries showed burning in vibration abuse tests, indicating high battery safety performance.

[0201] In the examples, compared to Examples 1 to 21, Examples 25 to 36 further contain a second polymer as a water-based adhesive, thereby forming a hydrogen bond and / or crosslinked structure between the first polymer and the second polymer, creating a high-density three-dimensional network crosslinked structure. This further enhances both the adhesive strength and water resistance of the coating, and improves the battery's cycle life and safety.

[0202] In Examples 30 to 36, the structural unit of formula (2) in the first polymer and the structural unit of formula (6) in the second polymer both contain a specific structure (hydroxypropyl ester), which significantly improves the adhesion of the water-based coating, enhances water resistance, and improves the cycle life and safety of the battery.

[0203] In contrast, in Comparative Examples 1-3, the coatings failed to achieve both high adhesive strength and high water resistance, resulting in poor battery cycle performance and affecting battery safety. Specifically, in Comparative Example 1, an oil-based coating slurry (adhesive PVDF + solvent NMP) was used on a water-based electrode plate. While the oil-based coating showed high water resistance in the water resistance test, its poor compatibility with the water-based electrode plate caused the coating to detach, resulting in very low adhesive strength, poor cycle performance, partial burning, and low battery safety. In Comparative Example 2, only polyacrylic acid was used as the adhesive, and in Comparative Example 3, only polypropylene hydroxyethyl was used as the adhesive. Since neither coating formed a three-dimensional network cross-linking structure, the water-based coatings could not obtain sufficient adhesive strength and water resistance, leading to a decrease in battery cycle performance and safety performance.

[0204] It should be noted that this application is not limited to the embodiments described above. The embodiments described above are merely illustrative, and any embodiment that has substantially the same configuration as the technical concept and achieves the same effects within the scope of the technical proposal of this application is included within the scope of the technical proposal of this application. Furthermore, other forms constructed by combining some of the components of the embodiments, with various modifications that a person skilled in the art could conceive of, are also included within the scope of this application, as long as they do not depart from the spirit of this application.

Claims

1. A water-based coating composition comprising an aqueous adhesive and a solvent, The aqueous adhesive comprises a first polymer, the first polymer comprising a structural unit shown in formula (1) and a structural unit shown in formula (2), 【Chemistry 19】 In equation (1), R １ , R ２ , R ３ Each of these is independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and L is a linkage bond or a C1-10 alkylene group. 【Chemistry 20】 In equation (2), R ４ , R ５ , R ６ A water-based coating composition characterized in that each of the groups is independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and n = 2 to 12.

2. In formula (1), R １ , R ２ , R ３ are each independently hydrogen, an alkyl group, a hydroxyalkyl group, an alkoxy group, a hydroxy group or a cyano group, and L is a linking bond or a C3-4 alkylene group, In equation (2), R ４ , R ５ , R ６ The aqueous coating composition according to claim 1, wherein each is independently a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxy group, a hydroxyl group, or a cyano group, and n = 3 to 6.

3. The aqueous coating composition according to claim 1 or 2, wherein in the first polymer, the mass occupancy rate of the structural unit shown in formula (1) is 10% to 75%, and the mass occupancy rate of the structural unit shown in formula (2) is 5% to 40%.

4. The first polymer further comprises the structural unit shown in formula (3) and / or the structural unit shown in formula (4), 【Chemistry 21】 In equation (3), R ７ , R ８ , R ９ Each of these is independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group. R １０ It is a rigid group, optionally a cyano group, an amide group, or an aryl group, optionally a cyano group, 【Chemistry 22】 In equation (4), R １１ , R １２ , R １３ The aqueous coating composition according to any one of claims 1 to 3, wherein each is independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and m = 2 to 12.

5. The aqueous coating composition according to claim 4, wherein the mass occupancy rate of the structural unit shown in formula (3) in the first polymer is 5% to 40%.

6. The aqueous coating composition according to claim 4, wherein the mass occupancy of the structural unit shown in formula (4) in the first polymer is 10% to 75%.

7. The aqueous coating composition according to any one of claims 4 to 6, wherein in the first polymer, the mass occupancy of the structural unit shown in formula (1) is 30% to 55%, the mass occupancy of the structural unit shown in formula (2) is 5% to 15%, the mass occupancy of the structural unit shown in formula (3) is 10% to 20%, and the mass occupancy of the structural unit shown in formula (4) is 30% to 55%.

8. The aqueous coating composition according to any one of claims 1 to 7, wherein the number-average molecular weight of the first polymer is 200,000 to 1,000,000, and optionally 300,000 to 600,000.

9. The aqueous adhesive further comprises a second polymer, the second polymer being different from the first polymer and containing groups that can interact with the first polymer. The aqueous coating composition according to any one of claims 1 to 8, wherein the group can form hydrogen bonds and / or crosslinked structures with the first polymer.

10. The second polymer contains a flexible group, The aqueous coating composition according to claim 9, wherein the flexible group is optionally a group containing an ester bond or a group containing an ether bond.

11. The second polymer comprises the structural unit shown in formula (5), the structural unit shown in formula (6), and the structural unit shown in formula (7). 【Chemistry 23】 In equation (5), R' １ , R' ２ , R' ３ These are R １ , R ２ , R ３ L' is either the same as or different from L, and each is independently a hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxyl group, cyano group, or nitro group, and L' is either the same as or different from L, and is a linkage bond or a C1-10 alkylene group. 【Chemistry 24】 In equation (6), R' ４ , R' ５ , R' ６ These are R ４ , R ５ , R ６ n' is either the same as or different from n, and each is independently a hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and n' is either the same as or different from n, and n' = 2 to 12. 【Chemistry 25】 In equation (7), R' １１ , R' １２ , R' １３ R １１ , R １２ , R １３ The aqueous coating composition according to claim 9 or 10, wherein m' is the same as or different from m, and each is independently hydrogen, halogen, alkyl group, hydroxyalkyl group, alkoxy group, cycloalkyl group, alkenyl group, alkynyl group, heterocycloalkyl group, aryl group, heteroaryl group, hydroxy group, cyano group, or nitro group, and m' is the same as or different from m, and m' = 2 to 12.

12. In equation (5), R' １ , R' ２ , R' ３ Each of these is independently a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxy group, a hydroxyl group, or a cyano group, and L' is a linking bond or a C3-4 alkylene group. In equation (6), R' ４ , R' ５ , R' ６ Each of these is independently a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxy group, a hydroxyl group, or a cyano group, and n' = 3 to 6. In equation (7), R' １１ , R' １２ , R' １３ The aqueous coating composition according to claim 11, wherein each is independently a hydrogen atom, an alkyl group, a hydroxyalkyl group, an alkoxy group, a hydroxyl group, or a cyano group, and m' = 3 to 6.

13. The aqueous coating composition according to claim 11 or 12, wherein in the second polymer, the mass occupancy of the structural unit shown in formula (5) is 10% to 60%, the mass occupancy of the structural unit shown in formula (6) is 5% to 20%, and the mass occupancy of the structural unit shown in formula (7) is 20% to 60%.

14. The structural unit of formula (2) is, 【Chemistry 26】 And, The structural unit of formula (6) is, 【Chemistry 27】 The aqueous coating composition according to any one of claims 11 to 13.

15. The aqueous coating composition according to any one of claims 9 to 14, wherein the number-average molecular weight of the second polymer is 200,000 to 1,200,000, and optionally 250,000 to 600,000.

16. The aqueous coating composition according to any one of claims 9 to 15, wherein the mass ratio of the first polymer to the second polymer is 9:1 to 1:9, and optionally 4:1 to 1:

4.

17. The aqueous coating composition according to any one of claims 1 to 16, wherein the solvent is water.

18. The composition further comprises an insulating material and / or a dispersant. Optionally, the insulating material is a ceramic material, and optionally, the ceramic material is boehmite powder. The aqueous coating composition according to any one of claims 1 to 17, wherein the dispersant is optionally a polyacrylamide-based dispersant.

19. A water-based electrode plate, including a water-based coating, The aqueous electrode plate is characterized in that the aqueous coating is formed from an aqueous coating composition according to any one of claims 1 to 18 and has a three-dimensional network crosslinking structure.

20. The aqueous electrode plate according to claim 19, wherein the aqueous coating contains 10% to 30% by mass, optionally 15% to 25% by mass, of an aqueous adhesive based on the total mass of the aqueous coating.

21. The aqueous electrode plate according to claim 19 or 20, wherein the aqueous coating contains 65% to 80% by mass of an insulating material and 0.2% to 1.0% by mass of a dispersant based on the total mass of the aqueous coating.

22. The aqueous electrode plate according to any one of claims 19 to 21, wherein the contact angle between the aqueous coating and water is 90° or less, and optionally between 40° and 80°.

23. The peel strength of the aqueous coating on the aqueous electrode plate is 10 N / m or more, and optionally 17 N / m or more. The aqueous electrode plate according to any one of claims 19 to 22, wherein the peel strength is obtained by performing a peel test in accordance with the national standard GB / T 41511-2022.

24. The aqueous electrode plate according to any one of claims 19 to 23, wherein the aqueous electrode plate is an aqueous positive electrode plate or an aqueous negative electrode plate.

25. A water-based battery characterized by including a water-based electrode plate according to any one of claims 19 to 24.

26. A power consumption device characterized by including the aqueous battery described in claim 25.

Images