Silicon-containing organic resin particle and preparation method therefor, silicon-containing organic resin particle dispersion, separator, secondary battery cell, battery apparatus, and electrical apparatus

Abstract

Provided are a silicon-containing organic resin particle and a preparation method therefor, a silicon-containing organic resin particle dispersion, a separator, a secondary battery cell, a battery apparatus, and an electrical apparatus. The separator comprises a porous base film and a porous coating on at least one side of the porous base film. The porous coating comprises silicon-containing organic resin particles. The initial thermal decomposition temperature T3d of the silicon-containing organic resin particles is 290°C -330°C. The secondary battery cell has high quality energy density, high reliability, and good high-temperature performance.

Description

Silicon-containing organic resin particle, method for producing the same, silicon-containing organic resin particle dispersion, separator, secondary battery cell, battery device, and electric device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese Patent Application No. 202411388765.7, filed on September 30, 2024, entitled “Silicon-containing organic resin particle, method for producing the same, silicon-containing organic resin particle dispersion, separator, secondary battery cell, battery device, and electric device,” the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to a silicon-containing organic resin particle, a method for producing the same, a silicon-containing organic resin particle dispersion, a separator, a secondary battery cell, a battery device, and an electric device. BACKGROUND

[0004] With the increasingly wide range of applications of secondary battery cells, people’s demand for the use of secondary battery cells is also increasing, for example, the requirements for the energy density and reliability of secondary battery cells are becoming higher and higher. Therefore, how to make the secondary battery cell have higher energy density under the premise of high reliability is a technical problem to be solved at present. SUMMARY

[0005] The present disclosure provides a silicon-containing organic resin particle, a method for producing the same, a silicon-containing organic resin particle dispersion, a separator, a secondary battery cell, a battery device, and an electric device, which have high mass energy density, high reliability, and good high-temperature performance.

[0006] In a first aspect, the present disclosure provides a separator, comprising a porous base film and a porous coating layer located on at least one side of the porous base film, the porous coating layer comprising silicon-containing organic resin particles, the silicon-containing organic resin particles having an initial thermal weight loss temperature T 3d of 290-330°C.

[0007] The silicon-containing organic resin particle has a small density, and the secondary battery cell using the same can have higher mass energy density. The silicon-containing organic resin particle has an initial thermal weight loss temperature T 3dThe high initial thermal weight loss temperature T of the silicon-containing organic resin particles indicates that the weight of the silicon-containing organic resin particles does not change significantly at high temperatures, thereby having high heat resistance and thermal stability, and not being prone to decomposition or pyrolysis during the use of the secondary battery cell and during the process of thermal abuse. By using the silicon-containing organic resin particles in the separator film, the silicon-containing organic resin particles can generate a force to resist the shrinkage of the separator film, thereby improving the thermal shrinkage of the entire separator film, improving the heat resistance of the separator film, and improving the reliability of the secondary battery cell. In addition, the silicon-containing organic resin particles have good stability in a high-temperature environment, and can also make the secondary battery cell have good high-temperature performance. Therefore, the separator film of the present disclosure can make the secondary battery cell have high-quality energy density, high reliability, and good high-temperature performance.

[0008] In some embodiments, the initial thermal weight loss temperature T of the silicon-containing organic resin particles is 300-330°C. 3d is 300-330°C.

[0009] In some embodiments, the silicon-containing organic resin particles have no melting point. The silicon-containing organic resin particles having no melting point indicate that the silicon-containing organic resin particles have good heat resistance and thermal stability, thereby being able to better resist the thermal shrinkage of the porous base film, improve the heat resistance of the separator film, and improve the reliability of the secondary battery cell.

[0010] In some embodiments, the silicon-containing organic resin particles have no glass transition temperature below 300°C. The silicon-containing organic resin particles having no glass transition temperature below 300°C indicate that the silicon-containing organic resin particles have good heat resistance and thermal stability, thereby being able to better resist the thermal shrinkage of the porous base film, improve the heat resistance of the separator film, and improve the reliability of the secondary battery cell.

[0011] In some embodiments, the silicon-containing organic resin particles have a dissolution rate of less than or equal to 3% when soaked in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at 60°C for 7 days. The silicon-containing organic resin particles have a low dissolution rate in organic solvents, have high structural stability during long-term use of the secondary battery cell, and have high chemical stability in electrolyte, thereby enabling the secondary battery cell to have longer cycle stability.

[0012] In some embodiments, the silicon-containing organic resin particles have a swelling degree of less than or equal to 3% when soaked in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at 60°C for 7 days. The silicon-containing organic resin particles have a low swelling degree in organic solvents, have high structural stability during long-term use of the secondary battery cell, and thereby improve the problem of decreased air permeability of the separator film during use.

[0013] In some embodiments, the cyclic voltammogram of the silicon-containing organic resin particles in the first cycle has no oxidation peak in the voltage range of 2.50V to 4.45V. The cyclic voltammogram of the silicon-containing organic resin particles in the first cycle has no oxidation peak in the voltage range of 2.50V to 4.45V, which indicates that the silicon-containing organic resin particles are stable in the voltage range of 2.50V to 4.45V. Therefore, the silicon-containing organic resin particles of the present disclosure have good electrochemical stability, can be applied in high-voltage secondary battery cells, improve the working voltage and energy density of the secondary battery cells, and also enable the secondary battery cells to have good capacity performance at high voltage.

[0014] In some embodiments, the silicon-containing organic resin particles have a true density of 1.1g / cm3 to 1.4g / cm3. 3 -1.4g / cm 3 .

[0015] In some embodiments, the silicon-containing organic resin particles include agglomerates of primary particles. The silicon-containing organic resin particles include agglomerates of primary particles, thereby increasing the size of the silicon-containing organic resin particles as a whole, which can be used in the separator membrane to effectively reduce the probability of small particles blocking the pores, and also enable the porous coating of the separator membrane to form more pores, thereby improving the electrolyte absorption and wettability of the separator membrane, and also enabling the secondary battery cell to have good cycle performance.

[0016] In some embodiments, the silicon-containing organic resin particles have a volume distribution particle size Dv50 of 300nm to 800nm. The volume distribution particle size Dv50 of the silicon-containing organic resin particles is within the above range, which is beneficial to the separator membrane having good heat resistance and air permeability.

[0017] In some embodiments, the primary particles in the agglomerates have a particle size of 30nm to 250nm.

[0018] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic cross-linked resin particles, and the silicon-containing organic resin particles contain carbon-carbon bonds and siloxane structures.

[0019] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic cross-linked resin particles, and the silicon-containing organic resin particles are network structures formed with carbon-carbon bonds as the main chain, and the side chains contain siloxane structures.

[0020] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic cross-linked resin particles, and the silicon-containing organic cross-linked resin particles include cross-linked structural units.

[0021] Optionally, the crosslinking structural unit includes one or more of a divinylbenzene structural unit, a diethylene glycol divinyl ether structural unit, a triethylene glycol divinyl ether structural unit, a diallyl maleate structural unit, a glycol dimethacrylate structural unit, a 1,4-butanediol diacrylate structural unit, a 1,6-hexanediol diacrylate structural unit, a 1,8-octanediol diacrylate structural unit, a trimethylolpropane triacrylate structural unit, a pentaerythritol trimethacrylate structural unit, a tetraethylene glycol dimethacrylate structural unit, a tripropylene glycol diacrylate structural unit, a 2,2,4-trimethyladipoyl bis[2-ethylaziridine] structural unit, a 1,1-sebacoyl bis[2-methylaziridine] structural unit, a 1,1-(1,3-phenylenedicarbonyl) bis[2-methylaziridine] structural unit, a trimethylolpropane tris(2-methyl-1-aziridinyl propionate) structural unit, a trimethylolpropane-tris[3-(2-methylaziridinyl)propionate] structural unit, a pentaerythritol tris(3-aziridinyl)propionate structural unit.

[0022] In some embodiments, the mass content of the silicon-containing organic resin particles in the porous coating is 50%-99% based on the total mass of the porous coating.

[0023] In some embodiments, the thickness of the porous coating is 0.5 μm-5 μm.

[0024] In some embodiments, the heat shrinkage rate of the release film in the longitudinal direction is less than or equal to 1.5% when heated at a constant temperature of 130°C for 1 h.

[0025] In some embodiments, the heat shrinkage rate of the release film in the transverse direction is less than or equal to 1.5% when heated at a constant temperature of 130°C for 1 h.

[0026] In some embodiments, the initial thermal weight loss temperature T 3d is 290°C-330°C.

[0027] In some embodiments, the initial thermal weight loss temperature T 3d is 300°C-330°C.

[0028] In some embodiments, the silicon-containing organic resin particles have no melting point.

[0029] In some embodiments, the silicon-containing organic resin particles have no glass transition temperature below 300°C.

[0030] In some embodiments, the dissolution rate of the silicon-containing organic resin particles is less than or equal to 3% when soaked in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at a constant temperature of 60°C for 7 days.

[0031] In some embodiments, the silicon-containing organic resin particles have a swelling degree of 3% or less when immersed in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at 60°C for 7 days.

[0032] In some embodiments, the silicon-containing organic resin particles do not have an oxidation peak in a voltage range of 2.50V to 4.45V in a cyclic voltammogram of the first cycle.

[0033] In some embodiments, the silicon-containing organic resin particles have a true density of 1.1g / cm 3 -1.4g / cm 3 .

[0034] In some embodiments, the silicon-containing organic resin particles include agglomerates of primary particles.

[0035] In some embodiments, the silicon-containing organic resin particles have a volume distribution particle size Dv50 of 300nm-800nm.

[0036] In some embodiments, the primary particles in the agglomerates have a particle size of 30nm-250nm.

[0037] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic resin particles contain carbon-carbon bonds and siloxane structures.

[0038] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic resin particles are network structures formed with carbon-carbon bonds as the main chain, and side chains containing siloxane structures.

[0039] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic crosslinked resin particles include crosslinked structure units.

[0040] Optionally, the crosslinking structure unit includes one or more of a divinylbenzene structure unit, a diethylene glycol divinyl ether structure unit, a triethylene glycol divinyl ether structure unit, a maleic acid diallyl ester structure unit, a ethylene glycol dimethacrylate structure unit, a 1,4-butanediol diacrylate structure unit, a 1,6-hexanediol diacrylate structure unit, a 1,8-octanediol diacrylate structure unit, a trimethylolpropane triacrylate structure unit, a pentaerythritol trimethacrylate structure unit, a tetraethylene glycol dimethacrylate structure unit, a tripropylene glycol diacrylate structure unit, a 2,2,4-trimethyladipoyl bis[2-ethylaziridine] structure unit, a 1,1-sebacoyl bis[2-methylaziridine] structure unit, a 1,1-(1,3-phenylenedicarbonyl) bis[2-methylaziridine] structure unit, a trimethylolpropane tris(2-methyl-1-aziridinyl propionate) structure unit, a trimethylolpropane-tris[3-(2-methylaziridinyl)propionate] structure unit, a pentaerythritol tris(3-aziridinyl) propionate structure unit.

[0041] In a third aspect, the present disclosure provides a method for preparing silicon-containing organic resin particles, comprising the steps of: providing a pre-emulsion comprising monomers, a crosslinking agent, an emulsifier, an initiator, and water, wherein the monomers comprise a silane coupling agent containing an alkenyl group and / or an acryloyloxy group; performing an emulsion polymerization reaction under heating, inert gas protection, and stirring conditions; drying the product obtained from the emulsion polymerization reaction; and then performing a baking process in an inert gas atmosphere, followed by a crushing process and a grinding process to obtain the silicon-containing organic resin particles.

[0042] In some embodiments, the temperature for drying the product obtained from the emulsion polymerization reaction is 80°C-150°C.

[0043] In some embodiments, the time for drying the product obtained from the emulsion polymerization reaction is 2h-12h.

[0044] In some embodiments, the drying method for the product obtained from the emulsion polymerization reaction includes vacuum drying, spray drying, air blowing drying, microwave drying, or fluidized bed drying.

[0045] In some embodiments, the temperature for the baking process is 160°C-250°C.

[0046] In some embodiments, the time for the baking process is 1h-8h.

[0047] In some embodiments, the grinding process comprises the steps of: mixing the material obtained from the crushing process with a solvent, a grinding medium, and optionally a dispersant to obtain a mixed slurry, and then performing a grinding process on the mixed slurry to obtain the silicon-containing organic resin particles.

[0048] Optionally, the solvent comprises one or more of water, methanol, ethanol.

[0049] Optionally, the dispersant comprises one or more of polyacrylic acid type dispersant, carboxymethyl cellulose type dispersant, polyethylene glycol, polyvinyl alcohol, polyvinyl pyrrolidone.

[0050] Optionally, the grinding medium comprises one or more of zirconia ball, alumina ball, silicon nitride ball.

[0051] Optionally, the average particle size of the grinding medium is 0.1mm-2mm.

[0052] Optionally, the filling rate of the grinding medium is 30%-80%.

[0053] Optionally, the rotation speed of the grinding is 500rpm-3000rpm.

[0054] In some embodiments, the heating temperature of the maturation stage of the emulsion polymerization reaction is 70℃-95℃.

[0055] In some embodiments, the heating time of the maturation stage of the emulsion polymerization reaction is 1h-5h.

[0056] In some embodiments, the inert gas comprises one or more of nitrogen, argon, helium.

[0057] In some embodiments, the emulsion polymerization reaction comprises the following steps: dropping the pre-emulsion into a reactor containing water under the conditions of a first temperature, inert gas protection and stirring, and after a first time, increasing the temperature to the heating temperature of the maturation stage to carry out the maturation reaction to obtain the silicon-containing organic resin particles.

[0058] In some embodiments, the first temperature is 55℃-70℃.

[0059] In some embodiments, the first time is 3h-6h.

[0060] In some embodiments, the monomer comprises one or more of gamma-methacryloxypropyl tris(trimethylsiloxy)silane, (3-acryloyloxypropyl)tris(trimethylsiloxy)silane, 3-methacryloxypropyltrimethoxysilane, acryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, acryloxypropyltriethoxysilane, gamma-methacryloxypropyltriisopropoxysilane, 3-(acryloxy)propyltrimethoxysilane, 3-methacryloxypropyltris(methoxyethoxy)silane, vinyltrimethoxysilane, 7-octenyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, tri-t-butoxyvinylsilane, vinyltris(beta-methoxyethoxy)silane, ethylene tris[(l-methylethenyl)oxy]silane, vinyltris-t-butylperoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxysilane, (3-acryloxy)dimethylmethoxysilane, 3-methacryloxypropyldimethylethoxysilane, diethylmethylvinylsilane, vinyl dimethyl ethoxysilane, methylvinyl diethoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, methylvinyl dimethoxysilane, 3-(methacryloxy)propylmethyldiethoxysilane.

[0061] In some embodiments, the crosslinking agent comprises one or more of divinylbenzene, diethylene glycol divinyl ether, triethylene glycol divinyl ether, maleic acid diallyl ester, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol trimethacrylate, tetraethylene glycol dimethacrylate, tripropylene glycol diacrylate, 2,2,4-trimethylhexanedioic acid bis[2-ethylaziridine], 1,1-nonanedioic acid bis[2-methylaziridine], 1,1-(1,3-phenylenedicarbonyl)bis[2-methylaziridine], trimethylolpropane tris(2-methyl-l-aziridinylpropionate), trimethylolpropane-tris[3-(2-methylaziridinyl)propionate], pentaerythritol tris(3-aziridinyl)propionate.

[0062] In some embodiments, the mass fraction of the crosslinking agent is 1.5-18% based on the total mass of the monomer and the crosslinking agent being 100%.

[0063] In a fourth aspect, the present disclosure provides a silicon-containing organic resin particle dispersion liquid including the silicon-containing organic resin particles of the second aspect and a dispersant, or obtained by the method of the third aspect.

[0064] In a fifth aspect, the present disclosure provides a secondary battery cell including a positive electrode sheet, a negative electrode sheet, and the separator of the first aspect of the present disclosure, the separator being disposed between the positive electrode sheet and the negative electrode sheet.

[0065] In a sixth aspect, the present disclosure provides a battery device including a plurality of the secondary battery cell of the fifth aspect of the present disclosure.

[0066] In a seventh aspect, the present disclosure provides an electric device including the secondary battery cell of the fifth aspect of the present disclosure or the battery device of the sixth aspect of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0067] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings needed to be used in the embodiments of the present disclosure will be briefly introduced below. Obviously, the drawings described below are only some of the embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the drawings.

[0068] FIG. 1 shows a schematic diagram of a secondary battery cell according to some embodiments of the present disclosure.

[0069] FIG. 2 shows a schematic diagram of an electric device according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0070] Hereinafter, specific embodiments of the present disclosure, including a silicon-containing organic resin particle and a method for producing the same, a silicon-containing organic resin particle dispersion liquid, a separator, a secondary battery cell, a battery device, and an electric device, will be described in detail with appropriate reference to the accompanying drawings. However, there will be cases where unnecessary detailed description is omitted. For example, there will be cases where detailed description of matters known well, redundant description of substantially identical structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate understanding by those skilled in the art. Furthermore, the drawings and the following description are provided so that those skilled in the art can fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

[0071] The ranges disclosed herein are defined by their lower and upper endpoints, given that a range is defined by selecting a lower endpoint and an upper endpoint, the selected lower and upper endpoints define the boundaries of the particular range. Ranges defined by endpoints can be either inclusive or exclusive of the endpoints, and can be arbitrarily combined, i.e., any lower endpoint can be combined with any upper endpoint to form a range. For example, if ranges of 60-120 and 80-110 are listed, it is understood that ranges of 60-110 and 80-120 are also contemplated. Also, if minimum range values of 1 and 2 are listed, and if maximum range values of 3, 4, and 5 are listed, then the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In the present disclosure, unless otherwise stated, a numerical range "a-b" indicates a shorthand way of describing all of the individual real combinations that fall between "a" and "b", where "a" and "b" are both real numbers. For example, the numerical range "0-5" indicates that all of the real numbers between "0" and "5" have been listed herein, and "0-5" is merely a shorthand way of describing these numerical combinations. In addition, when a parameter is stated to be an integer ≥ 2, it is equivalent to disclose that the parameter is, for example, integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0072] Unless otherwise specified, all embodiments and optional embodiments of the present disclosure can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present disclosure.

[0073] Unless otherwise specified, all technical features and optional technical features of the present disclosure can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present disclosure.

[0074] Unless otherwise specified, all steps of the present disclosure can be performed in sequence or randomly, and preferably in sequence. For example, the method comprises steps (a) and (b), which means that the method can comprise steps (a) and (b) in sequence, or steps (b) and (a) in sequence. For example, the method also comprises step (c), which means that step (c) can be added to the method in any order, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0075] Unless otherwise specified, in the present disclosure, the terms "first", "second", etc. are used to distinguish different objects, and are not used to describe a particular order or primary and secondary relationship.

[0076] In the present disclosure, the terms "a plurality of", "a plurality of" refer to two or more.

[0077] In the description of the embodiments of the present disclosure, if there is no special indication, the first feature is "on" or "under" the second feature, which can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature can be "above", "over" and "on" the second feature, which can be that the first feature is directly above or obliquely above the second feature, or only means that the horizontal height of the first feature is higher than that of the second feature. The first feature can be "below", "under" and "under" the second feature, which can be that the first feature is directly below or obliquely below the second feature, or only means that the horizontal height of the first feature is less than that of the second feature.

[0078] Unless otherwise specified, the test temperature of each parameter mentioned in the present disclosure is 25°C.

[0079] The secondary battery cell mentioned in the embodiments of the present disclosure can realize the function of charging and discharging independently, and can continue to be used by activating the active material through charging after discharging. The secondary battery cell can be in the shape of a cylinder, a cuboid or other shapes, which are not limited in the embodiments of the present disclosure. As shown in FIG. 1, the secondary battery cell 5 is a cuboid structure as an example.

[0080] The secondary battery cell provided by the embodiments of the present disclosure can include but is not limited to lithium battery cells, sodium battery cells, such as lithium ion battery cells, sodium ion battery cells, lithium metal battery cells, sodium metal battery cells, etc.

[0081] The secondary battery cell provided by the embodiments of the present disclosure includes an electrode assembly. The electrode assembly can be a winding structure or a stacking structure, which is not limited in the embodiments of the present disclosure. The secondary battery cell further includes an outer package, which can be used to package the electrode assembly. The outer package can be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The outer package can also be a soft package, such as a bag-type soft package. The material of the soft package can be plastic, such as one or more of aluminum plastic film, polypropylene, polybutylene terephthalate (PBT) and polybutylene succinate (PBS).

[0082] The battery apparatus mentioned in the embodiments of the present disclosure can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of secondary battery cells connected in series, in parallel or in a mixed manner through a busbar component.

[0083] In some embodiments, the battery cell assembly is usually formed by arranging a plurality of secondary battery cells.

[0084] As an example, the battery cell assembly can be a battery module, which is formed by arranging and fixing a plurality of secondary battery cells into one independent module. As an example, the battery module can be formed by bundling a plurality of secondary battery cells with a cable tie.

[0085] In some embodiments, the battery device can be a battery pack, which includes a case and one or more battery cell assemblies accommodated in the case.

[0086] As an example, the battery cell assembly can be a battery module, which can be accommodated in the case by fixing the battery module in the case.

[0087] As an example, the battery cell assembly can also be accommodated in the case by directly fixing a plurality of secondary battery cells in the case.

[0088] As an example, the case can include a first case and a second case. The first case and the second case are fastened so that an enclosed space is formed inside the case to accommodate the battery cell assembly. Here, the enclosed means covered or closed, which can be sealed or unsealed. The first case can be a top cover or a bottom plate.

[0089] As an example, the case can include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are connected to the frame, respectively, so that an enclosed space is formed inside the case to accommodate the battery cell assembly.

[0090] In some embodiments, the case can be part of a chassis structure of a vehicle. For example, part of the case can be at least part of a floor of the vehicle, or part of the case can be at least part of a cross beam and a longitudinal beam of the vehicle.

[0091] The technical solutions described in the embodiments of the present disclosure are applicable to various electric devices using secondary battery cells and battery devices, such as, but not limited to, mobile devices (such as mobile phones, tablet computers, notebook computers, etc.), electric vehicles (such as 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. The secondary battery cells and the battery devices are used to store or provide electric energy.

[0092] FIG. 2 is a schematic diagram of an electric device as an example. The electric device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc.

[0093] In the context of the present disclosure, the silicon-containing organic resin particles mainly play a role in improving heat resistance in the porous coating of the separator film, and basically have no adhesion effect.

[0094] The separator film is an important component for supporting the secondary battery cell to complete the charge and discharge electrochemical process. The commonly used separator film is mostly polyolefin material. However, the heat resistance of the polyolefin material is poor, which is easy to soften or melt at high temperature, thereby causing the short circuit of the secondary battery cell. In order to improve the heat resistance of the separator film, a porous coating layer is usually coated on the separator film to improve the heat resistance of the separator film. The inorganic particles such as boehmite and aluminum oxide are commonly used heat-resistant fillers. However, the density of the heat-resistant fillers is large, and the mass is large under the same packing volume, thereby affecting the energy density of the secondary battery cell.

[0095] Therefore, the silicon-containing organic resin particles of the present disclosure are used in the separator film, which can make the secondary battery cell have high mass energy density, high reliability and good high temperature performance.

[0096] The initial thermal weight loss temperature T 3d of the silicon-containing organic resin particles of the present disclosure is 290-330°C.

[0097] The density of the silicon-containing organic resin particles is small, and the secondary battery cell using the same can have higher mass energy density. The initial thermal weight loss temperature T 3d of the silicon-containing organic resin particles is high, which indicates that the weight of the silicon-containing organic resin particles does not change obviously at high temperature, thereby having high heat resistance and thermal stability, and not being easy to decompose or pyrolyze during the use process and thermal abuse process of the secondary battery cell. By using the silicon-containing organic resin particles in the separator film, the silicon-containing organic resin particles can generate a force to resist the shrinkage of the separator film, thereby improving the overall thermal shrinkage of the separator film, improving the heat resistance of the separator film, and improving the reliability of the secondary battery cell. In addition, the silicon-containing organic resin particles have good stability in a high temperature environment, and can also make the secondary battery cell have good high temperature performance.

[0098] Therefore, the silicon-containing organic resin particles of the present disclosure are used in the separator film, which can make the secondary battery cell have high mass energy density, high reliability and good high temperature performance.

[0099] Optionally, the initial thermal weight loss temperature T 3d of the silicon-containing organic resin particles can be 300-330°C.

[0100] The initial thermal weight loss temperature T 3d is the temperature corresponding to the loss of 3% of the initial mass of the sample in the thermal gravimetric analysis. The initial thermal weight loss temperature T 3dThe test can be performed as follows: take an appropriate amount of sample (for example, 5 mg-15 mg) and place it in an alumina crucible of a thermal gravimetric analyzer (TGA), shake it flat, and cover it with a crucible cover; parameter settings: nitrogen atmosphere, purge gas 60 mL / min, protective gas 20 mL / min; temperature rising program: temperature rising rate 10 ℃ / min, temperature range 35-600 ℃; obtain the temperature corresponding to a 3% loss in sample mass relative to the initial mass (i.e., 97% of the initial mass) from the test curve, which is the initial thermal weight loss temperature T 3d .

[0101] In some embodiments, the true density of the silicon-containing organic resin particles can be 1.1 g / cm 3 -1.4 g / cm 3 .

[0102] At present, the true density of inorganic particles such as boehmite and alumina is usually 2.5 g / cm 3 -3.5 g / cm 3 The true density of the silicon-containing organic resin particles of the present disclosure is small, so that the secondary battery cell using the separator film of the present disclosure has a higher mass energy density.

[0103] The silicon-containing organic resin particles of the present disclosure are neither soluble in water nor in organic solvents such as tetrahydrofuran (THF), dichloromethane (DCM), dimethylformamide (DMF), trichlorobenzene (TCB), chloroform at 25°C, i.e., not soluble in the mobile phase for gel permeation chromatography test, and the molecular weight of the silicon-containing organic resin particles cannot be tested by gel permeation chromatography.

[0104] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic crosslinked resin particles contain carbon-carbon bonds and siloxane structures.

[0105] Alternatively, the silicon-containing organic resin particles are network structures formed with carbon-carbon bonds as the main chain, and the side chains contain siloxane structures.

[0106] Alternatively, the silicon-containing organic resin particles are network structures formed with carbon-carbon bonds as the main chain, and the side chains contain siloxane structures and benzene ring structures.

[0107] In some embodiments, the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic crosslinked resin particles include crosslinked structure units.

[0108] The crosslinked structure unit of the silicon-containing organic crosslinked resin particles refers to a silicon-free structure unit used to connect the silicon-containing structure units.

[0109] In some embodiments, the crosslinking structural unit can include one or more of a divinylbenzene structural unit, a diethylene glycol divinyl ether structural unit, a triethylene glycol divinyl ether structural unit, a maleic acid diallyl ester structural unit, a ethylene glycol dimethacrylate structural unit, a 1,4-butanediol diacrylate structural unit, a 1,6-hexanediol diacrylate structural unit, a 1,8-octanediol diacrylate structural unit, a trimethylolpropane triacrylate structural unit, a pentaerythritol trimethacrylate structural unit, a tetraethylene glycol dimethacrylate structural unit, a tripropylene glycol diacrylate structural unit, a 2,2,4-trimethyl adipic acid bis[2-ethylaziridine] structural unit, a 1,1-sebacic acid bis[2-methylaziridine] structural unit, a 1,1-(1,3-phenylenedicarbonyl) bis[2-methylaziridine] structural unit, a trimethylolpropane tris(2-methyl-1-aziridinyl propionate) structural unit, a trimethylolpropane-tris[3-(2-methylaziridinyl) propionate] structural unit, a pentaerythritol tris(3-aziridinyl) propionate structural unit.

[0110] Optionally, the crosslinking structural unit can include a divinylbenzene structural unit.

[0111] Optionally, the crosslinking structural unit can include a divinylbenzene structural unit and one or more of a diethylene glycol divinyl ether structural unit, a triethylene glycol divinyl ether structural unit, a maleic acid diallyl ester structural unit, a ethylene glycol dimethacrylate structural unit, a 1,4-butanediol diacrylate structural unit, a 1,6-hexanediol diacrylate structural unit, a 1,8-octanediol diacrylate structural unit, a trimethylolpropane triacrylate structural unit, a pentaerythritol trimethacrylate structural unit, a tetraethylene glycol dimethacrylate structural unit, a tripropylene glycol diacrylate structural unit, a 2,2,4-trimethyl adipic acid bis[2-ethylaziridine] structural unit, a 1,1-sebacic acid bis[2-methylaziridine] structural unit, a 1,1-(1,3-phenylenedicarbonyl) bis[2-methylaziridine] structural unit, a trimethylolpropane tris(2-methyl-1-aziridinyl propionate) structural unit, a trimethylolpropane-tris[3-(2-methylaziridinyl) propionate] structural unit, a pentaerythritol tris(3-aziridinyl) propionate structural unit.

[0112] In some embodiments, the silicon-containing organic resin particles have no melting point.

[0113] The silicon-containing organic resin particles of the present disclosure have no melting point, indicating that they have good heat resistance and thermal stability, and thus can better resist thermal shrinkage of the porous base film, improve the heat resistance of the separator film, and improve the reliability of the secondary battery cell.

[0114] The melting point can be tested as follows: take an appropriate amount of sample (for example, 5-15 mg) and place it in a differential scanning calorimeter (DSC) crucible, shake it flat, and cover it with a crucible cover; parameter settings: nitrogen atmosphere, purge gas 60 mL / min, protective gas 20 mL / min; program settings: temperature rise from 25°C to 200°C at a rate of 10°C / min, hold for 5 min to eliminate thermal history, temperature drop from 200°C to -40°C at a rate of 10°C / min, and temperature rise from -40°C to 300°C at a rate of 10°C / min. Determine whether the silicon-containing organic resin particles have a melting point below 300°C by the DSC curve. The silicon-containing organic resin particles have no melting point, meaning that the DSC curve of the silicon-containing organic resin particles has no melting peak.

[0115] In some embodiments, the silicon-containing organic resin particles have no glass transition temperature below 300°C.

[0116] The silicon-containing organic resin particles have no glass transition temperature below 300°C, indicating that they have good heat resistance and thermal stability, and thus can better resist the thermal shrinkage of the porous base film, improve the heat resistance of the isolation film, and improve the reliability of the secondary battery cell.

[0117] The glass transition temperature T g The melting point can be tested as follows: take an appropriate amount of sample (for example, 5-15 mg) and place it in a differential scanning calorimeter (DSC) crucible, shake it flat, and cover it with a crucible cover; parameter settings: nitrogen atmosphere, purge gas 60 mL / min, protective gas 20 mL / min; program settings: temperature rise from 25°C to 200°C at a rate of 10°C / min, hold for 5 min to eliminate thermal history, temperature drop from 200°C to -40°C at a rate of 10°C / min, and temperature rise from -40°C to 300°C at a rate of 10°C / min. Determine whether the silicon-containing organic resin particles have a melting point below 300°C by the DSC curve. The silicon-containing organic resin particles have no melting point, meaning that the DSC curve of the silicon-containing organic resin particles has no melting peak. g .

[0118] The glass transition temperature T g is the temperature at which the glass state changes to the high-elasticity state, which appears as a step change on the DSC curve.

[0119] The silicon-containing organic resin particles have no glass transition temperature T g below 300°C, meaning that the DSC curve of the silicon-containing organic resin particles has no step change below 300°C.

[0120] In some embodiments, the silicon-containing organic resin particles have a dissolution rate of less than or equal to 3% when soaked in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at 60°C for 7 days.

[0121] The silicon-containing organic resin particles have a low dissolution rate in an organic solvent, high structural stability during long-term use of a secondary battery cell, and high chemical stability in an electrolyte, thereby providing a secondary battery cell with long cycle stability.

[0122] The dissolution rate of the silicon-containing organic resin particles can be tested by the following method: taking an appropriate amount of sample (e.g., about 1 g) and weighing it as m1, placing it in a semi-permeable membrane sample bag, sealing the bag, recording the total mass of the sample bag m2, and immersing the sample bag in an appropriate amount of solvent (e.g., about 50 g) at 60°C for 7 days. Then, the sample bag is removed, drained, dried, and weighed again as m3. The dissolution rate is (m2-m3) / m1 x 100%. The solvent is a mixed solvent of ethylene carbonate (EC) and methyl ethyl carbonate (EMC) in a volume ratio of 3:7.

[0123] In some embodiments, the silicon-containing organic resin particles have a swelling degree of less than or equal to 3% in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at 60°C for 7 days.

[0124] The silicon-containing organic resin particles have a low swelling degree in an organic solvent, high structural stability during long-term use of a secondary battery cell, and thereby improve the problem of decreased air permeability of the separator during use.

[0125] The swelling degree of the silicon-containing organic resin particles can be tested by the following method: taking an appropriate amount of sample (e.g., about 1 g) and weighing it as m1, placing it in a semi-permeable membrane sample bag, sealing the bag, and immersing the sample bag in an appropriate amount of solvent (e.g., about 50 g) at 60°C for 7 days. Then, the sample bag is removed, and the sample is removed from the sample bag, wiped to remove excess solvent, and weighed again as m2. The swelling degree is (m2-m1) / m1 x 100%. The solvent is a mixed solvent of ethylene carbonate (EC) and methyl ethyl carbonate (EMC) in a volume ratio of 3:7.

[0126] In some embodiments, the silicon-containing organic resin particles have no oxidation peak in the cyclic voltammetry curve of the first cycle in the voltage range of 2.50V to 4.45V.

[0127] The cyclic voltammogram of the silicon-containing organic resin particles in the first cycle has no oxidation peak in the voltage range of 2.50V to 4.45V, which indicates that the silicon-containing organic resin particles are stable in the voltage range of 2.50V to 4.45V. Therefore, the silicon-containing organic resin particles of the present disclosure have good electrochemical stability, can be applied in high-voltage secondary battery cells, improve the working voltage and energy density of the secondary battery cells, and also enable the secondary battery cells to have good capacity performance at high voltage.

[0128] The oxidation peak potential of the cyclic voltammogram of the silicon-containing organic resin particles can be tested as follows: the silicon-containing organic resin particles, the binder polyacrylate, and the conductive agent conductive carbon black are dissolved in water in a solid content mass ratio of 64:7:29 to prepare a slurry, the slurry is coated on an aluminum foil as a positive electrode, a lithium foil is used as a negative electrode, and a button cell is assembled; the button cell is subjected to cyclic voltammetry (CV) test, the scanning rate is 0.10mV / s, the voltage range is 2.50V-5.00V, and the cycle is 3 cycles, and the voltage corresponding to the peak point of the first cycle cyclic voltammogram is taken as the oxidation peak potential. The electrolyte salt of the electrolyte used for testing is LiPF6, and the concentration is 1mol / L. The solvent of the electrolyte is obtained by mixing ethylene carbonate (EC) and methyl ethyl carbonate (EMC) in a volume ratio of 3:7.

[0129] In some embodiments, the silicon-containing organic resin particles include agglomerates of primary particles.

[0130] Generally, the agglomerates of primary particles can also be referred to as secondary particles.

[0131] The silicon-containing organic resin particles include agglomerates of primary particles, thereby increasing the size of the silicon-containing organic resin particles as a whole, which can be used in the separator film to effectively reduce the probability of small particle hole blocking, and also enable the porous coating layer of the separator film to form more pores, thereby improving the electrolyte absorption and wettability of the separator film, and also enabling the secondary battery cell to have good cycle performance.

[0132] In some embodiments, the volume distribution particle size Dv50 of the silicon-containing organic resin particles can be 300nm-800nm, for example, can be 300nm, 320nm, 360nm, 400nm, 440nm, 480nm, 520nm, 560nm, 600nm, 640nm, 680nm, 720nm, 760nm, 780nm, or a range consisting of any of the above values.

[0133] The volume distribution particle size Dv50 of the silicon-containing organic resin particles in the above range is beneficial to the separator film to have good heat resistance and air permeability.

[0134] Optionally, the volume distribution particle size Dv50 of the silicon-containing organic resin particles can be 320 nm-800 nm, 360 nm-800 nm, 400 nm-800 nm, 320 nm-760 nm, 360 nm-760 nm, 400 nm-760 nm, 320 nm-720 nm, 360 nm-720 nm, or 400 nm-720 nm.

[0135] Dv50 represents the particle size corresponding to the cumulative volume distribution percentage of 50%, which can be tested by a laser particle size analyzer according to GB / T 19077-2016. During the test, 1 g of the sample to be tested is added to a clean small beaker, 20 ml of deionized water is added, and ultrasonic treatment is performed at 53 KHz / 120 W for 5 min to ensure that the sample is completely dispersed. After the light path system is cleaned, the background is automatically tested. The sample to be tested is stirred to make it uniformly dispersed, and then placed in the sample cell according to the requirements, and the particle size is measured. The test instrument can be a MasterSizer 3000 laser particle size analyzer.

[0136] In some embodiments, the primary particles in the agglomerates can have a particle size of 30 nm-250 nm. Optionally, the primary particles in the agglomerates can have a particle size of 30 nm-240 nm, 30 nm-220 nm, 30 nm-200 nm, 30 nm-180 nm, 30 nm-160 nm, 30 nm-150 nm, 50 nm-240 nm, 50 nm-220 nm, 50 nm-200 nm, 50 nm-180 nm, 50 nm-160 nm, 50 nm-150 nm, 80 nm-240 nm, 80 nm-220 nm, 80 nm-200 nm, 80 nm-180 nm, 80 nm-160 nm, 80 nm-150 nm, 85 nm-240 nm, 85 nm-220 nm, 85 nm-200 nm, 85 nm-180 nm, 85 nm-160 nm, 85 nm-150 nm, 90 nm-240 nm, 90 nm-220 nm, 90 nm-200 nm, 90 nm-180 nm, 90 nm-160 nm, or 90 nm-150 nm.

[0137] The particle size of the primary particles can be tested by the following method: the silicon-containing organic resin particle powder is laid and adhered on the conductive glue to form a sample to be tested with a length x width of 6 cm x 1.1 cm; the particle morphology is tested by a scanning electron microscope (such as ZEISS Sigma 300), and the test can refer to JY / T010-1996. The particle size of the primary particles is measured in the scanning electron microscope image.

[0138] The present disclosure also provides a method for preparing the silicon-containing organic resin particles.

[0139] The method for preparing the silicon-containing organic resin particles includes the following steps: providing a pre-emulsion containing monomers, a cross-linking agent, an emulsifier, an initiator, and water, wherein the monomers include a silane coupling agent containing an alkenyl group and / or an acryloyloxy group; performing an emulsion polymerization reaction under the conditions of heating, inert gas protection, and stirring; drying the product obtained from the emulsion polymerization reaction, and then performing baking in an inert gas atmosphere; and finally performing a crushing process and a grinding process to obtain the silicon-containing organic resin particles.

[0140] The monomers include a silane coupling agent containing an alkenyl group and / or an acryloyloxy group, so that free radicals are generated between the monomers, cross-linking reactions occur, and the monomers also undergo cross-linking reactions with the cross-linking agent. Therefore, the silicon-containing organic resin particles with a three-dimensional network molecular structure can be formed using the monomers and the cross-linking agent of the present disclosure, and the silicon-containing organic resin particles have high heat resistance and are not prone to softening or deformation at high temperatures.

[0141] The silicon-containing organic resin particles obtained by drying the product obtained from the emulsion polymerization reaction and then performing baking in an inert gas atmosphere have a high initial thermal weight loss temperature T 3d The silicon-containing organic resin particles have a high initial thermal weight loss temperature T

[0142] In some embodiments, the method for drying the product obtained from the emulsion polymerization reaction can include, but is not limited to, vacuum drying, spray drying, air blowing drying, microwave drying, or fluidized bed drying.

[0143] In some embodiments, the temperature for drying the product obtained from the emulsion polymerization reaction can be 80-150°C, for example, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C, or a range formed by any of the above values.

[0144] In some embodiments, the time for drying the product obtained from the emulsion polymerization reaction can be 2-12h, for example, 2h, 2.4h, 2.8h, 3.2h, 3.6h, 4h, 4.4h, 4.8h, 5.2h, 5.6h, 6h, 6.4h, 6.8h, 7.2h, 7.6h, 8h, 8.4h, 8.8h, 9.2h, 9.6h, 10h, 10.4h, 10.8h, 11.2h, 11.6h, 12h, or a range formed by any of the above values.

[0145] The baking is performed in an inert gas atmosphere. In some embodiments, the inert gas can include one or more of nitrogen, argon, and helium.

[0146] In some embodiments, the temperature of the baking process can be 160-250℃, for example, can be 160℃, 165℃, 170℃, 175℃, 180℃, 185℃, 190℃, 195℃, 200℃, 205℃, 210℃, 215℃, 220℃, 225℃, 230℃, 235℃, 240℃, 245℃, 250℃, or a range consisting of any of the aforementioned values.

[0147] In some embodiments, the time of the baking process can be 1-8h, for example, can be 1h, 1.2h, 1.4h, 1.6h, 1.8h, 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, 3.2h, 3.4h, 3.6h, 3.8h, 4h, 4.2h, 4.4h, 4.6h, 4.8h, 5h, 5.2h, 5.4h, 5.6h, 5.8h, 6h, 6.2h, 6.4h, 6.6h, 6.8h, 7h, 7.2h, 7.4h, 7.6h, 7.8h, 8h, or a range consisting of any of the aforementioned values. Alternatively, the time of the baking process can be 2-8h, 2.4-8h, 3-8h.

[0148] In some embodiments, the crushing process can employ an air jet mill, a vibration mill, a mechanical crusher, an ultrasonic crusher, a ball mill, etc.

[0149] In some embodiments, the grinding process can comprise the following steps: mixing the material after the crushing process with a solvent, a grinding medium, and optionally a dispersant to obtain a mixed slurry, and then subjecting the mixed slurry to a grinding process to obtain the silicon-containing organic resin particles.

[0150] Alternatively, the solvent can comprise one or more of water, methanol, ethanol. More alternatively, the solvent can comprise water.

[0151] Alternatively, the dispersant can comprise one or more of a polyacrylic acid type dispersant, a carboxymethyl cellulose type dispersant, polyethylene glycol, polyvinyl alcohol, polyvinylpyrrolidone. Alternatively, the polyacrylic acid type dispersant can comprise one or more of polyacrylic acid, sodium polyacrylate, potassium polyacrylate, ammonium acrylate. Alternatively, the carboxymethyl cellulose type dispersant can comprise one or more of carboxymethyl cellulose, sodium carboxymethyl cellulose, potassium carboxymethyl cellulose.

[0152] Alternatively, the grinding medium can comprise one or more of zirconium oxide balls, aluminum oxide balls, silicon nitride balls.

[0153] Alternatively, the average particle size of the grinding medium can be 0.1-2mm.

[0154] Optionally, the filling rate of the grinding medium can be 30%-80%. In this way, the grinding medium can be in sufficient contact with the silicon-containing organic resin particles, and the grinding treatment effect can be improved.

[0155] Optionally, the rotation speed of the grinding can be 500 rpm-3000 rpm, for example, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, 1200 rpm, 1300 rpm, 1400 rpm, 1500 rpm, 1600 rpm, 1700 rpm, 1800 rpm, 1900 rpm, 2000 rpm, 2100 rpm, 2200 rpm, 2300 rpm, 2400 rpm, 2500 rpm, 2600 rpm, 2700 rpm, 2800 rpm, 2900 rpm, 3000 rpm, or a range consisting of any of the above values.

[0156] In some embodiments, the heating temperature of the maturation stage of the emulsion polymerization reaction can be 70°C-95°C, for example, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, or a range consisting of any of the above values.

[0157] In some embodiments, the heating time of the maturation stage of the emulsion polymerization reaction can be 1h-5h, for example, 1h, 1.2h, 1.4h, 1.6h, 1.8h, 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, 3.2h, 3.4h, 3.6h, 3.8h, 4h, 4.2h, 4.4h, 4.6h, 4.8h, 5h, or a range consisting of any of the above values.

[0158] The emulsion polymerization reaction is carried out under the protection of inert gas. In some embodiments, the inert gas can include one or more of nitrogen, argon, and helium.

[0159] In some embodiments, the emulsion polymerization reaction can include the following steps: under the conditions of a first temperature, protection of inert gas, and stirring, the pre-emulsion is added dropwise into a reactor containing water, and after reacting for a first time, the temperature is raised to the heating temperature of the maturation stage for maturation reaction to obtain the silicon-containing organic resin particles.

[0160] In some embodiments, the first temperature can be 55°C-70°C.

[0161] In some embodiments, the first time can be 3h-6h.

[0162] The crosslinking agent forms, after polymerization with the monomer, a crosslinking structural unit of the silicon-containing organic crosslinked resin particles.

[0163] In some embodiments, the crosslinking agent can be a multifunctional crosslinking agent.

[0164] Optionally, the crosslinking agent can include one or more of divinylbenzene, diethylene glycol divinyl ether, triethylene glycol divinyl ether, maleic acid diallyl ester, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol trimethacrylate, tetraethylene glycol dimethacrylate, dipentaerythritol diacrylate, 2,2,4-trimethyladipic acid bis[2-ethylaziridine], 1,1-nonanedioic acid bis[2-methylaziridine], 1,1-(1,3-phenylenedicarbonyl)bis[2-methylaziridine], trimethylolpropane tris(2-methyl-1-aziridinyl propionate), trimethylolpropane-tris[3-(2-methylaziridinyl)propionate], pentaerythritol tris(3-aziridinyl)propionate.

[0165] Optionally, the crosslinking agent can include divinylbenzene.

[0166] Optionally, the crosslinking agent can include divinylbenzene and one or more of diethylene glycol divinyl ether, triethylene glycol divinyl ether, maleic acid diallyl ester, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol trimethacrylate, tetraethylene glycol dimethacrylate, dipentaerythritol diacrylate, 2,2,4-trimethyladipic acid bis[2-ethylaziridine], 1,1-nonanedioic acid bis[2-methylaziridine], 1,1-(1,3-phenylenedicarbonyl)bis[2-methylaziridine], trimethylolpropane tris(2-methyl-1-aziridinyl propionate), trimethylolpropane-tris[3-(2-methylaziridinyl)propionate], pentaerythritol tris(3-aziridinyl)propionate.

[0167] In some embodiments, the monomer can include a vinylsilane coupling agent and / or an acryloxy silane coupling agent.

[0168] Optionally, the monomer can include one or more of gamma-methacryloxypropyl tris(trimethylsiloxy)silane, (3-acryloyloxypropyl)tris(trimethylsiloxy)silane, 3-methacryloxypropyltrimethoxysilane, acryloyloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, acryloyloxypropyltriethoxysilane, gamma-methacryloxypropyltriisopropoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-methacryloxypropyltris(methoxyethoxy)silane, vinyltrimethoxysilane, 7-octenyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, tri-t-butoxyvinylsilane, vinyltris(beta-methoxyethoxy)silane, ethylene tris[(l-methylethenyl)oxy]silane, vinyltris-t-butylperoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxysilane, (3-acryloxy)dimethylmethoxysilane, 3-methacryloxypropyldimethylethoxysilane, diethylmethylvinylsilane, vinyl dimethyl ethoxysilane, methylvinyl diethoxysilane, vinylmethyl dimethoxysilane, vinylmethyl diethoxysilane, methylvinyl dimethoxysilane, 3-(methacryloxy)propylmethyldiethoxysilane.

[0169] In some embodiments, the mass fraction of the crosslinking agent can be 1.5%-18%, for example, can be 1.5%, 3%, 4%, 5%, 6%, 7%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, 15%, 16%, 17%, 18%, or a range consisting of any of the aforementioned values, based on 100% of the total mass of the monomer and the crosslinking agent. The mass fraction of the crosslinking agent in the above range can result in a silicon-containing organic resin particle with good heat resistance.

[0170] Optionally, the mass fraction of the crosslinking agent can be 4%-18%, 6%-18%, 8%-18%, 4%-16%, 6%-16%, 8%-16%, 4%-15%, 6%-15%, 8%-15%.

[0171] In some embodiments, the emulsifier can include, but is not limited to, one or more of alkyl sulfate, alkyl sulfonate, Tween emulsifier, fatty alcohol polyoxyethylene ether, fatty alcohol polyoxypropylene ether, cetyl stearyl alcohol polyether, oleyl ether. Optionally, the emulsifier includes one or more of sodium dodecyl sulfate, sodium dodecyl sulfonate, Tween 20, Tween 40, laureth-7, laureth-9, laureth-10, oleyl ether-10.

[0172] In some embodiments, the initiator can include, but is not limited to, one or more of sodium persulfate, potassium persulfate, ammonium persulfate, sodium sulfite, sodium bisulfite, azobisisobutyronitrile, azobisisobutyramidine hydrochloride, azobisisobutylimidazole hydrochloride, azobisisopropylimidazole.

[0173] In some embodiments, the mass fraction of the initiator can be 0.15%-2.5%, for example, can be 0.15%, 0.2%, 0.3%, 0.4%, 0.5%, 0.7%, 0.9%, 1.1%, 1.3%, 1.5%, 1.7%, 1.9%, 2.1%, 2.3%, 2.5%, or a range consisting of any of the above values, based on 100% of the total mass of the monomer and the crosslinking agent.

[0174] Alternatively, the mass fraction of the initiator can be 0.3%-2.1%, 0.3%-1.9%, 0.3%-1.7%, 0.3%-1.5%, 0.3%-1.3%.

[0175] In some embodiments, the pre-emulsion can further include a pH adjuster. Alternatively, the pH adjuster can include, but is not limited to, one or more of sodium bicarbonate, sodium hydroxide, ammonia water, and the like.

[0176] The embodiments of the present disclosure further provide a silicon-containing organic resin particle dispersion liquid, which includes the silicon-containing organic resin particles described above and a dispersant, or is obtained by the preparation method of the silicon-containing organic resin particles of the present disclosure.

[0177] The embodiments of the present disclosure further provide an isolation film.

[0178] The isolation film includes a porous base film and a porous coating layer located on at least one side of the porous base film, and the porous coating layer includes a binder and the silicon-containing organic resin particles of the present disclosure or the silicon-containing organic resin particles prepared by the method of the present disclosure.

[0179] Both the porous base film and the porous coating layer have a pore structure, so that the isolation film has good air permeability and facilitates the passage of ions. The silicon-containing organic resin particles in the porous coating layer are connected to each other and fixed by the binder, and the gaps between the silicon-containing organic resin particles can form a pore structure.

[0180] In some embodiments, the mass content of the silicon-containing organic resin particles in the porous coating layer can be 50%-99%, based on the total mass of the porous coating layer.

[0181] Optionally, the mass content of the silicon-containing organic resin particles in the porous coating layer can be 60%-99%, 70%-99%, 80%-99%, 85%-99%, 88%-99%, 80%-97%, 85%-97%, 88%-97%, 80%-95%, 85%-95%, 88%-95%.

[0182] In some embodiments, the binder in the porous coating layer can include, but is not limited to, one or more of polyacrylate binders, nitrile rubber binders, polyacrylic acid, polymethacrylic acid, sodium polyacrylate, polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), and carboxymethyl chitosan (CMCS).

[0183] In some embodiments, the porous coating layer can further include a dispersant, which can include, but is not limited to, polyacrylate dispersants or carboxymethyl cellulose dispersants. As an example, the dispersant can include, but is not limited to, one or more of sodium carboxymethyl cellulose, sodium polyacrylate, ammonium polyacrylate.

[0184] In some embodiments, the separator film can further include polymeric binder particles.

[0185] The "polymeric binder particles" in the porous coating layer of the separator film play a role in improving the adhesion of the separator film to the electrode sheet, and have substantially no high-temperature resistance.

[0186] In some embodiments, the polymeric binder particles can be embedded in the silicon-containing organic resin particles and form protrusions on the surface of the porous coating layer.

[0187] In other embodiments, the porous coating layer of the separator film includes a heat-resistant layer disposed on the porous base film and a bonding layer disposed on at least a portion of the surface of the heat-resistant layer away from the porous base film, the silicon-containing organic resin particles are disposed in the heat-resistant layer, and the polymeric binder particles are disposed in the bonding layer.

[0188] In yet other embodiments, the porous coating layer of the separator film includes a heat-resistant layer disposed on one side of the porous base film and a bonding layer disposed on at least a portion of the surface of the other side of the porous base film, the silicon-containing organic resin particles are disposed in the heat-resistant layer, and the polymeric binder particles are disposed in the bonding layer.

[0189] In some embodiments, the average particle size of the polymeric binder particles can be 6-18 μm.

[0190] In some embodiments, the polymeric binder particles can include vinylidene fluoride-based polymer particles, such as polyvinylidene fluoride (PVDF) particles and / or copolymer particles of a vinylidene fluoride monomer and a comonomer.

[0191] The comonomer can include at least one of an olefin monomer, a fluorine-containing olefin monomer, a chlorine-containing olefin monomer, an acrylate monomer, an acrylic monomer, and a fluorine ether monomer.

[0192] Optionally, the comonomer can include at least one of trifluoroethylene, trifluorochloroethylene, 1,2-difluoroethylene, tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl) ether (e.g., perfluoro(methyl vinyl) ether, perfluoro(ethyl vinyl) ether, perfluoro(propyl vinyl) ether), perfluoro(1,3-dioxolane), and perfluoro(2,2-dimethyl-1,3-dioxolane).

[0193] In some embodiments, the porous coating layer can have a thickness of 0.5 μm to 5 μm. The thickness of the porous coating layer refers to the thickness of the porous coating layer on one side of the porous base film. Optionally, the thickness of the porous coating layer can be 0.5 μm to 4 μm, 0.5 μm to 3 μm, 0.5 μm to 2 μm, 0.6 μm to 4 μm, 0.6 μm to 3 μm, 0.6 μm to 2 μm, 0.8 μm to 4 μm, 0.8 μm to 3 μm, 0.8 μm to 2 μm.

[0194] In some embodiments, the porous base film can include a film or nonwoven web selected from any one or at least two of polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyacetal, polyamide, polycarbonate, polyimide, polyether ether ketone, polyaryletherketone, polyetherimide, polyamideimide, polybenzimidazole, polyether sulfone, polyphenylene ether, cyclic olefin copolymer, polyphenylene sulfide, and polyvinyl naphthalene.

[0195] The porous base film can be a single-layer film or a multi-layer composite film. When the porous base film is a multi-layer composite film, the materials of the layers can be the same or different.

[0196] In some embodiments, the porous base film can have a thickness of 4 μm to 12 μm, optionally 4 μm to 9 μm.

[0197] In some embodiments, the porous base film can have a porosity of 25% to 60%, optionally 28% to 50%.

[0198] In some embodiments, the separator film can have a thickness of 5 μm to 14 μm, optionally 5 μm to 12 μm, 6 μm to 12 μm. This is advantageous for improving the energy density of the secondary battery cell.

[0199] In some embodiments, the separator film can have a longitudinal (MD) heat shrinkage of less than or equal to 1.5% when heated at 130°C for 1 h.

[0200] In some embodiments, the isolation film has a transverse direction (TD) heat shrinkage of less than or equal to 1.5% at 130°C for 1 hour.

[0201] It should be noted that the porous coating parameters of the isolation film described above are the porous coating parameters of one side of the porous base film. When the porous coating is arranged on both sides of the porous base film, as long as the porous coating parameters of any one side meet the present disclosure, it is considered to fall within the protection scope of the present disclosure.

[0202] The isolation film can be prepared according to methods known in the art.

[0203] In some embodiments, a slurry including silicon-containing organic resin particles and a binder can be coated on at least one side of the porous base film, and after drying, the isolation film is obtained.

[0204] In some embodiments, the slurry can further include polymer binder particles, and after drying of the slurry, the polymer binder particles are embedded in the silicon-containing organic resin particles and form protrusions on the surface of the porous coating.

[0205] In some embodiments, the method for preparing the isolation film can include: a step of coating a heat-resistant layer slurry including silicon-containing organic resin particles and a binder on at least one side of the porous base film, and after drying, forming a heat-resistant layer; and a step of coating an adhesive layer slurry including polymer binder particles and a binder on at least a part of the surface of the heat-resistant layer, and after drying, obtaining the isolation film.

[0206] In some embodiments, the method for preparing the isolation film can include: a step of coating a heat-resistant slurry including silicon-containing organic resin particles and a binder on one side of the porous base film, and a step of coating an adhesive layer slurry including polymer binder particles and a binder on at least a part of the surface of the other side of the porous base film, and after drying, obtaining the isolation film.

[0207] In some embodiments, the solvent of the slurry can be water, for example, deionized water.

[0208] In some embodiments, the slurry can further include other components, for example, can further include dispersants and / or wetting agents, etc.

[0209] The present disclosure also provides a secondary battery cell. The secondary battery cell includes the isolation film provided by the embodiments of the present disclosure.

[0210] The secondary battery cell further includes a positive electrode sheet, a negative electrode sheet, and an electrolyte, and the isolation film is arranged between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet, the isolation film, and the negative electrode sheet can form an electrode assembly through a rolling process and / or a stacking process.

[0211] The secondary battery cell provided by the present disclosure can include, but is not limited to, a lithium battery cell, a sodium battery cell, etc., and the type of the secondary battery cell is different, and the composition of the positive electrode sheet, the negative electrode sheet and the electrolyte will be different.

[0212] [Positive electrode sheet]

[0213] In some embodiments, the positive electrode sheet can include a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector and including a positive electrode active material. For example, the positive electrode current collector has two surfaces opposite in the thickness direction of itself, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.

[0214] For example, the positive electrode active material can include, but is not limited to, one or more of lithium transition metal oxides, lithium-containing phosphates, and their respective modified compounds. Examples of the lithium transition metal oxides can include, but are not limited to, one or more of lithium cobalt oxides, lithium nickel oxides, lithium manganese oxides, lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, lithium nickel cobalt manganese oxides, lithium nickel cobalt aluminum oxides, and their respective modified compounds. Examples of the lithium-containing phosphates can include, but are not limited to, one or more of lithium iron phosphate, a composite of lithium iron phosphate and carbon, lithium manganese phosphate, a composite of lithium manganese phosphate and carbon, lithium manganese iron phosphate, a composite of lithium manganese iron phosphate and carbon, and their respective modified compounds. In some embodiments, in order to further improve the energy density of the secondary battery cell, the positive electrode active material can include one or more of lithium transition metal oxides of the general formula Li a Ni b Co c M d O e A f 0.8≤a≤1.2, 0.5≤b<1, 0<c<1, 0<d<1, 1≤e≤2, 0≤f≤1, M includes but is not limited to one or more of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti and B, and A includes but is not limited to one or more of N, F, S and Cl.

[0215] For example, the positive electrode active material can include, but is not limited to, LiCoO2, LiNiO2, LiMnO2, LiMn2O4, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2(NCM523), LiNi 0.6 Co 0.2 Mn 0.2O2(NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2(NCM811), LiNi 0.85 Co 0.1 Al 0.05 O2, LiFePO4, LiMnPO4.

[0216] The secondary battery cell will be accompanied by Li de-intercalation and consumption during charging and discharging process, and the molar content of Li is different when the secondary battery cell is discharged to different states. In the enumeration of the positive electrode active material in this disclosure, the molar content of Li is the initial state of the material, that is, the state before feeding, and the positive electrode active material is applied to the secondary battery cell. After charging and discharging cycle, the molar content of Li will change. In the enumeration of the positive electrode active material in this disclosure, the molar content of O is only the theoretical state value, and the lattice oxygen release will cause the molar content of O to change, and the actual molar content of O will also appear floating.

[0217] Taking a sodium battery cell as an example, the positive electrode active material can include but is not limited to one or more of sodium-containing transition metal oxides, polyanion materials (such as phosphates, fluorophosphates, pyrophosphates, sulfates, etc.), prussian blue type materials. As an example, the positive electrode active material can include but is not limited to NaFeO2, NaCoO2, NaCrO2, NaMnO2, NaNiO2, NaNi 1 / 2 Ti 1 / 2 O2, NaNi 1 / 2 Mn 1 / 2 O2, Na 2 / 3 Fe 1 / 3 Mn 2 / 3 O2, NaNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2, NaFePO4, NaMnPO4, NaCoPO4, prussian blue type material, material of general formula X p M’ q (PO4) r O x Y 3-x , one or more of the materials. In the general formula X p M’ q (PO4) r O x Y 3-x , 0 + , Li + , Na + , K + and NH4 +M' is a transition metal cation, optionally including but not limited to one or more of V, Ti, Mn, Fe, Co, Ni, Cu, and Zn, Y is a halide anion, optionally one or more of F, Cl, and Br.

[0218] The modified compound of the positive electrode active material of each of the above lithium battery cell and sodium battery cell can be a doping modification and / or a surface coating modification to the positive electrode active material.

[0219] In some embodiments, the positive electrode film layer can further include a positive electrode conductive agent. As an example, the positive electrode conductive agent can include but is not limited to one or more of super P, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0220] In some embodiments, the positive electrode film layer can further include a positive electrode binder. As an example, the positive electrode binder can include but is not limited to one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, and a fluorine-containing acrylic resin.

[0221] In some embodiments, the positive electrode current collector can be a metal foil or a composite current collector. As an example of the metal foil, an aluminum foil can be used. The composite current collector can include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material can include but is not limited to one or more of aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver, and a silver alloy. As an example, the polymer material base layer can include but is not limited to one or more of polypropylene, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene, and polyethylene.

[0222] The positive electrode film layer is generally formed by coating a positive electrode slurry on the positive electrode current collector, drying, and cold-pressing. The positive electrode slurry is generally formed by dispersing and uniformly stirring the positive electrode active material, the positive electrode conductive agent, the positive electrode binder, and any other components in a solvent. The solvent can be N-methyl pyrrolidone (NMP), but is not limited thereto.

[0223] [Negative electrode tab]

[0224] In some embodiments, the negative electrode tab can include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector and including a negative electrode active material. For example, the negative electrode current collector has two surfaces opposite in the thickness direction thereof, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0225] The negative active material can employ materials known in the art that are useful for secondary battery cells. As an example, the negative active material can include, but is not limited to, one or more of natural graphite, artificial graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate. The silicon-based materials can include, but are not limited to, one or more of elemental silicon, silicon oxide, silicon-carbon composite, silicon-nitrogen composite, and silicon alloy materials. The tin-based materials can include, but are not limited to, one or more of elemental tin, tin oxide, and tin alloy materials.

[0226] In some embodiments, the negative electrode film layer can further include a negative electrode conductive agent. As an example, the negative electrode conductive agent can include, but is not limited to, one or more of super P, conductive graphite, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0227] In some embodiments, the negative electrode film layer can further include a negative electrode binder. As an example, the negative electrode binder can include, but is not limited to, one or more of styrene butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (e.g., polyacrylic acid PAA, polymethylacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), and carboxymethyl chitosan (CMCS).

[0228] In some embodiments, the negative electrode film layer can further include other auxiliary agents. As an example, the other auxiliary agents can include thickening agents, such as sodium carboxymethyl cellulose (CMC), PTC thermistor materials, and the like.

[0229] In some embodiments, the negative electrode current collector can employ a metal foil or a composite current collector. As an example of a metal foil, a copper foil can be employed. The composite current collector can include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material can include, but is not limited to, one or more of copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy. As an example, the polymer material base layer can include, but is not limited to, one or more of polypropylene, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene, and polyethylene.

[0230] The negative electrode film layer is typically formed by coating a negative electrode slurry on a negative electrode current collector, drying, and cold-pressing. The negative electrode slurry is typically formed by dispersing the negative active material, the negative electrode conductive agent, the negative electrode binder, and other optional auxiliary agents in a solvent and stirring uniformly. The solvent can be N-methyl pyrrolidone (NMP) or deionized water, but is not limited thereto.

[0231] The negative electrode tab does not exclude other additional functional layers in addition to the negative electrode film layer. For example, in some embodiments, the negative electrode tab also includes a conductive primer layer (e.g., composed of a conductive agent and a binder) sandwiched between the negative electrode current collector and the negative electrode film layer, disposed on the surface of the negative electrode current collector.

[0232] In some embodiments, the negative electrode tab can employ a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, foamed carbon, etc. When the foamed metal is used as the negative electrode tab, the surface of the foamed metal can not be provided with a negative electrode active material, and of course can be provided with a negative electrode active material.

[0233] [Electrolyte]

[0234] The electrolyte plays a role in conducting ions between the positive electrode tab and the negative electrode tab.

[0235] In some embodiments, the electrolyte employs an electrolyte solution, which includes an electrolyte salt and an organic solvent.

[0236] Taking a lithium battery cell as an example, the electrolyte salt can include but is not limited to one or more of lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4), lithium hexafluoroarsenate (LiAsF6), lithium bisfluorosulfonylimide (LiFSI), lithium bis-trifluoromethanesulfonylimide (LiTFSI), lithium trifluoromethanesulfonate (LiTFS), lithium difluorooxalate borate (LiDFOB), lithium difluorophosphate (LiPO2F2), lithium difluorodioxalate phosphate (LiDFOP), and lithium tetrafluorooxalate phosphate (LiTFOP).

[0237] Taking a sodium battery cell as an example, the electrolyte salt can include but is not limited to one or more of sodium hexafluorophosphate (NaPF6), sodium tetrafluoroborate (NaBF4), sodium perchlorate (NaClO4), sodium hexafluoroarsenate (NaAsF6), sodium bisfluorosulfonylimide (NaFSI), sodium bis-trifluoromethanesulfonylimide (NaTFSI), sodium trifluoromethanesulfonate (NaTFS), sodium difluorooxalate borate (NaDFOB), sodium difluorophosphate (NaPO2F2), sodium difluorodioxalate phosphate (NaDFOP), and sodium tetrafluorooxalate phosphate (NaTFOP).

[0238] In some embodiments, the organic solvent can include, but is not limited to, one or more of ethylene carbonate (EC), propylene carbonate (PC), methyl ethyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), butylene carbonate (BC), methyl formate (MF), methyl acetate (MA), ethyl acetate (EA), propyl acetate (PA), methyl propionate (MP), ethyl propionate (EP), propyl propionate (PP), methyl butyrate (MB), ethyl butyrate (EB), 1,4-butyrolactone (GBL), sulfolane (SF), dimethyl sulfone (MSM), methyl ethyl sulfone (EMS), diethyl sulfone (ESE), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, crown ether.

[0239] In some embodiments, an additive can also be included in the electrolyte. For example, the additive can include a negative electrode film-forming additive, can also include a positive electrode film-forming additive, and can also include an additive capable of improving certain performance of the secondary battery cell, such as an additive capable of improving overcharge performance, an additive capable of improving high-temperature performance, an additive capable of improving low-temperature performance, and the like.

[0240] Optionally, the additive can include one or more of fluoroethylene carbonate (FEC), vinylene carbonate (VC), 1,3-propane sultone (PS), and vinyl sulfate (DTD).

[0241] Methods for preparing secondary battery cells are well known. In some embodiments, a positive electrode sheet, a separator, a negative electrode sheet, and an electrolyte can be assembled to form a secondary battery cell. As an example, a positive electrode sheet, a separator, and a negative electrode sheet can be formed into an electrode assembly through a winding process and / or a stacking process, the electrode assembly can be placed in an outer package, an electrolyte described above can be injected after drying, and the secondary battery cell can be obtained through processes such as vacuum packaging, standing, and formation.

[0242] Embodiments

[0243] The following examples describe the present disclosure in more detail, which are merely illustrative and not intended to limit the scope of the present disclosure, as various modifications and variations are obvious to those skilled in the art. Unless otherwise stated, all parts, percentages, and ratios reported in the following examples are based on mass, and all reagents used in the examples are commercially available or synthesized according to conventional methods and used as received without further purification, and the instruments used in the examples are commercially available.

[0244] Example 1

[0245] Preparation of the separator film

[0246] A pre-emulsion was prepared by emulsifying 0.3 g of sodium persulfate, 0.3 g of sodium bicarbonate, 1.5 g of sodium dodecyl sulfate, 30 g of deionized water, 52 g of gamma-methacryloxypropyl triisopropoxy silane, 3 g of 3-methacryloxypropyl triethoxysilane and 5 g of divinyl benzene. A reactor was taken, 210 g of deionized water was added, and the temperature was raised to 70°C. The pre-emulsion was added dropwise under nitrogen protection and stirring. After 4 h of reaction, the temperature was raised to 84°C for 1.5 h of curing reaction. The product of the emulsion polymerization reaction was dried in a vacuum drying oven at 105°C for 8 h, and then transferred to a rotary furnace for baking at 180°C for 2 h under a nitrogen atmosphere to obtain a block solid. The block solid was naturally cooled in air, broken by an air flow crusher, mixed with water and wet ground to obtain a dispersion of silicon-containing organic resin particles 1#.

[0247] The dispersion, the binder polymethyl methacrylate and the dispersant sodium carboxymethyl cellulose were uniformly stirred in deionized water to obtain a heat-resistant layer slurry. The solid mass ratio of the silicon-containing organic resin particles, the dispersant sodium carboxymethyl cellulose and the binder polymethyl methacrylate in the heat-resistant layer slurry was 90:2:8.

[0248] Commercial polyvinylidene fluoride particles, a binder polymethyl methacrylate, a dispersant sodium carboxymethyl cellulose and an ether-based surfactant were uniformly stirred in deionized water at a solid mass ratio of 87:8:3:2 to obtain an adhesive layer slurry.

[0249] A commercially available polyethylene microporous film with a thickness of 7 μm was used as a porous base film. The heat-resistant layer slurry was coated on both surfaces of the porous base film by micro-gravure method, and after drying, the adhesive layer slurry was sprayed on the heat-resistant layer. After drying and slitting, the separator film was obtained.

[0250] Preparation of a secondary battery cell

[0251] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O2, a positive electrode binder polyvinylidene fluoride (PVDF) and a positive electrode conductive agent carbon black were mixed in N-methyl pyrrolidone (NMP) at a mass ratio of 97:2:1, and then uniformly stirred to prepare a positive electrode slurry. The positive electrode slurry was uniformly coated on a positive electrode current collector aluminum foil, and then dried, cold-pressed and slitted to obtain a positive electrode sheet.

[0252] The negative active material artificial graphite, the negative electrode conductive agent acetylene black, the negative electrode binder styrene butadiene rubber (SBR), and the thickening agent sodium carboxymethyl cellulose are added into deionized water according to a mass ratio of 96.0:1.5:1.5:1, and a negative electrode slurry is prepared after being fully stirred and mixed uniformly; the negative electrode slurry is uniformly coated on the negative electrode current collector copper foil, and then is subjected to drying, cold pressing, and slitting to obtain a negative electrode sheet.

[0253] Vinyl carbonate (EC) and methyl ethyl carbonate (EMC) are mixed according to a volume ratio of 3:7 to obtain a mixed solvent, and then LiPF6, vinylene carbonate (VC), and vinyl sulfate (DTD) are dissolved in the mixed solvent to obtain an electrolyte. The concentration of LiPF6 is 1 mol / L. The mass fraction of VC is 2%, and the mass fraction of DTD is 3%, based on the mass of the electrolyte.

[0254] The positive electrode sheet, the separator, and the negative electrode sheet are stacked in sequence and wound and hot-pressed to obtain an electrode assembly, and then the electrode assembly is loaded into a hard-shell outer package, and then the secondary battery monomer is obtained through processes such as electrolyte injection, standing, and formation.

[0255] Example 2

[0256] The preparation of the secondary battery monomer is the same as that in Example 1, except for the following differences.

[0257] Preparation of the separator

[0258] A pre-emulsion is prepared by emulsifying 0.3 g of sodium persulfate, 0.3 g of sodium bicarbonate, 1.5 g of sodium dodecyl sulfate, 30 g of deionized water, 52 g of γ-methacryloxypropyl triisopropoxy silane, 3 g of 3-methacryloxypropyl triethoxysilane, and 5 g of divinylbenzene. A reactor is taken, 210 g of deionized water is added, and the temperature is raised to 70°C. Under the conditions of nitrogen protection and stirring, the pre-emulsion is added dropwise, and after reaction for 4 h, the temperature is raised to 84°C for curing reaction for 1.5 h. The product obtained by emulsion polymerization is dried in a vacuum drying oven at 105°C for 8 h, and then transferred to a rotary furnace and baked at 200°C for 2 h under a nitrogen atmosphere to obtain a block solid. After natural cooling in air, the block solid is broken by an air flow crusher and wet ground with water to obtain a silicon-containing organic resin particle 2# dispersion.

[0259] The above dispersion, the binder polymethyl methacrylate, and the dispersant sodium carboxymethyl cellulose are uniformly stirred in deionized water to obtain a heat-resistant layer slurry. The solid mass ratio of the silicon-containing organic resin particles, the dispersant sodium carboxymethyl cellulose, and the binder polymethyl methacrylate in the heat-resistant layer slurry is 90:2:8.

[0260] The commercially available polyvinylidene fluoride particles, the binder polymethyl methacrylate, the dispersant sodium carboxymethyl cellulose and the ether-based surfactant were uniformly stirred in deionized water at a solid content mass ratio of 87:8:3:2 to obtain the adhesive layer slurry.

[0261] A commercially available polyethylene microporous film with a thickness of 7 μm was used as the porous base film. The heat-resistant layer slurry was coated on both surfaces of the porous base film by microgravure, and after drying, the adhesive layer slurry was sprayed on the heat-resistant layer. Then, through drying and slitting processes, the separator film was obtained.

[0262] Example 3

[0263] The preparation of the secondary battery cell was the same as that of Example 1, except for the following differences.

[0264] Preparation of the separator film

[0265] A pre-emulsion was prepared by emulsifying 0.3 g of sodium persulfate, 0.3 g of sodium bicarbonate, 1.5 g of sodium dodecyl sulfate, 30 g of deionized water, 52 g of γ-methacryloxypropyl triisopropoxy silane, 3 g of 3-methacryloxypropyl triethoxysilane and 5 g of divinyl benzene. A reactor was taken, 210 g of deionized water was added, and the temperature was raised to 70°C. Under the conditions of nitrogen protection and stirring, the above-mentioned pre-emulsion was added dropwise, and after reaction for 4 h, the temperature was raised to 84°C for curing reaction for 1.5 h. The product obtained by emulsion polymerization was dried in a vacuum drying oven at 105°C for 8 h, and then transferred to a rotary furnace for baking at 220°C for 2 h under a nitrogen atmosphere to obtain a block solid. After natural cooling in air, the block solid was broken by an air jet pulverizer and wet ground with water to obtain a silicon-containing organic resin particle 3# dispersion.

[0266] The above-mentioned dispersion, the binder polymethyl methacrylate and the dispersant sodium carboxymethyl cellulose were uniformly stirred in deionized water to obtain the heat-resistant layer slurry. The solid mass ratio of the silicon-containing organic resin particles, the dispersant sodium carboxymethyl cellulose and the binder polymethyl methacrylate in the heat-resistant layer slurry was 90:2:8.

[0267] The commercially available polyvinylidene fluoride particles, the binder polymethyl methacrylate, the dispersant sodium carboxymethyl cellulose and the ether-based surfactant were uniformly stirred in deionized water at a solid content mass ratio of 87:8:3:2 to obtain the adhesive layer slurry.

[0268] A commercially available polyethylene microporous film with a thickness of 7 μm was used as the porous base film. The heat-resistant layer slurry was coated on both surfaces of the porous base film by microgravure, and after drying, the adhesive layer slurry was sprayed on the heat-resistant layer. Then, through drying and slitting processes, the separator film was obtained.

[0269] Example 4

[0270] The preparation of the secondary battery cell was the same as that of Example 1, except for the following differences.

[0271] Preparation of the separator

[0272] A pre-emulsion was prepared by emulsifying 0.3 g of sodium persulfate, 0.3 g of sodium bicarbonate, 1.5 g of sodium dodecyl sulfate, 30 g of deionized water, 52 g of γ-methacryloxypropyl triisopropoxysilane, 3 g of 3-methacryloxypropyl triethoxysilane, and 5 g of divinyl benzene. A reactor was taken, 210 g of deionized water was added, and the temperature was raised to 70°C. The pre-emulsion was added dropwise under nitrogen protection and stirring. After 4 h of reaction, the temperature was raised to 84°C for 1.5 h of curing reaction. The product of the emulsion polymerization reaction was dried in a vacuum drying oven at 105°C for 8 h, and then transferred to a rotary furnace for baking at 240°C for 2 h under a nitrogen atmosphere to obtain a block solid. The block solid was naturally cooled in air, broken by an air flow crusher, and wet ground with water to obtain a dispersion of silicon-containing organic resin particles 4#.

[0273] The above dispersion, the binder polymethyl methacrylate, and the dispersant sodium carboxymethyl cellulose were uniformly stirred in deionized water to obtain a heat-resistant layer slurry. The solid mass ratio of the silicon-containing organic resin particles, the dispersant sodium carboxymethyl cellulose, and the binder polymethyl methacrylate in the heat-resistant layer slurry was 90:2:8.

[0274] Commercially available polyvinylidene fluoride particles, the binder polymethyl methacrylate, the dispersant sodium carboxymethyl cellulose, and the ether-based surfactant were uniformly stirred in deionized water at a solid mass ratio of 87:8:3:2 to obtain an adhesive layer slurry.

[0275] A commercially available polyethylene microporous film with a thickness of 7 μm was used as the porous base film. The heat-resistant layer slurry was coated on both surfaces of the porous base film by micro-gravure method, and after drying, the adhesive layer slurry was sprayed on the heat-resistant layer. After drying and slitting, the separator was obtained.

[0276] Comparative Example 1

[0277] The preparation of the secondary battery cell was the same as that of Example 1, except for the following differences.

[0278] Preparation of the separator

[0279] A pre-emulsion was prepared by emulsifying 0.3 g of sodium persulfate, 0.3 g of sodium bicarbonate, 1.5 g of sodium dodecyl sulfate, 30 g of deionized water, 52 g of γ-methacryloxypropyl triisopropoxysilane, 3 g of 3-methacryloxypropyl triethoxysilane, and 5 g of divinyl benzene. A reactor was taken, 210 g of deionized water was added, and the temperature was raised to 70°C. The pre-emulsion was added dropwise under nitrogen protection and stirring. After 4 h of reaction, the temperature was raised to 84°C for 1.5 h of curing reaction. The product of the emulsion polymerization reaction was dried in a vacuum drying oven at 105°C for 8 h, and then transferred to a rotary furnace for baking at 240°C for 2 h under a nitrogen atmosphere to obtain a block solid. The block solid was naturally cooled in air, broken by an air flow crusher, and wet ground with water to obtain a dispersion of silicon-containing organic resin particles 4#.

[0280] The above emulsion, the binder polymethyl methacrylate and the dispersant sodium carboxymethyl cellulose were stirred uniformly in deionized water to obtain a heat-resistant layer slurry. The solid mass ratio of the silicon-containing organic resin particles, the dispersant sodium carboxymethyl cellulose and the binder polymethyl methacrylate in the heat-resistant layer slurry was 90:2:8.

[0281] The commercially available polyvinylidene fluoride particles, the binder polymethyl methacrylate, the dispersant sodium carboxymethyl cellulose and the ether-based surfactant were stirred uniformly in deionized water at a solid content mass ratio of 87:8:3:2 to obtain an adhesive layer slurry.

[0282] A commercially available polyethylene microporous film with a thickness of 7 μm was used as a porous base film. The heat-resistant layer slurry was coated on both surfaces of the porous base film by microgravure coating, and after drying, the adhesive layer slurry was sprayed on the heat-resistant layer, and then dried and cut to obtain an isolation film.

[0283] The silicon-containing organic resin particles 1# to 4# prepared above meet the following characteristics: the silicon-containing organic resin particles form a network structure with carbon-carbon bonds as the main chain, and the side chains contain siloxane structures and benzene ring structures, and the silicon-containing organic resin particles have no melting point and no glass transition temperature T g .

[0284] Performance Test

[0285] (1) Initial thermal weight loss temperature T 3d Test

[0286] An appropriate amount of sample (e.g. 5-15 mg) was placed in an alumina crucible of a thermal gravimetric analyzer (TGA), leveled, and covered with a crucible cover; the parameters were set as follows: nitrogen atmosphere, purging gas 60 mL / min, protective gas 20 mL / min; temperature rising program: temperature rising rate 10 ℃ / min, temperature range 35-600 ℃; the temperature corresponding to the loss of 3% of the initial mass (i.e. 97% of the initial mass) of the sample from the test curve was obtained, which was the initial thermal weight loss temperature T 3d .

[0287] (2) Cyclic voltammetry test of silicon-containing organic resin particles

[0288] Take the silicon-containing organic resin particles, the binder polymethyl methacrylate, and the conductive agent conductive carbon black according to the solid content mass ratio 64:7:29 to dissolve in water to configure a slurry, coat the slurry on an aluminum foil as a positive electrode, take a lithium foil as a negative electrode, and assemble a button cell; perform a cyclic voltammetry (CV) test on the button cell, the scanning rate is 0.10 mV / s, the voltage range is 2.50V-5.00V, and the cycle is 3 cycles, and the voltage corresponding to the peak point of the first cycle of the cyclic voltammetry curve is taken as the oxidation peak potential. The electrolyte salt of the electrolyte used for the test is LiPF6, and the concentration is 1 mol / L. The solvent of the electrolyte is obtained by mixing ethylene carbonate (EC) and methyl ethyl carbonate (EMC) according to a volume ratio of 3:7.

[0289] (3) Heat shrinkage rate test of the separator film

[0290] The heat shrinkage rate test of the separator film can refer to GB / T 36363-2018.

[0291] The separator film is punched into a sample with a width of 50 mm and a length of 100 mm by a punch press, 5 parallel samples are placed on an A4 paper, and then the A4 paper containing the samples is placed on corrugated paper with a thickness of 1 mm to 5 mm.

[0292] The temperature of the air blowing oven is set to 130℃, after the temperature reaches the set temperature and stabilizes for 60 min, the A4 paper placed on the corrugated paper is put into the air blowing oven, the timing starts, and after the set time (1h in the present disclosure) is reached, the length and width of the separator film are measured, and the values are marked as a and b respectively.

[0293] Heat shrinkage rate calculation: longitudinal (MD) heat shrinkage rate = [(100-a) / 100]x100%, transverse (TD) heat shrinkage rate = [(50-b) / 50]x100%, and the average value of 3 parallel samples is taken as the test result.

[0294] (4) High temperature storage performance test of the secondary battery cell

[0295] The secondary battery cell was charged at 25℃ with a constant current of 1 / 3C to 4.25V, then charged at a constant voltage of 4.25V until the current was 0.05C, and then left for 5min, and then discharged at a constant current of 1 / 3C to 2.8V, and the obtained discharge capacity was recorded as the pre-storage capacity C0; then the secondary battery cell was charged at a constant current of 1 / 3C to 4.25V, and then charged at a constant voltage of 4.25V until the current was 0.05C, at which time the secondary battery cell was in a full charge state; the full charge state secondary battery cell was placed in a 60℃ constant temperature oven for storage for 30 days, after which the secondary battery cell was taken out, and when the temperature of the secondary battery cell dropped to 25℃, it was discharged at a constant current of 1 / 3C to 2.8V, and the obtained discharge capacity was recorded as the post-storage capacity C1. The capacity retention rate of the secondary battery cell stored at 60℃ for 30 days = post-storage capacity C1 / pre-storage capacity C0x100%.

[0296] Table 1

[0297] From the above test results, it can be seen that the silicon-containing organic resin particles with an initial thermal weight loss temperature T 3d The silicon-containing organic resin particles with an initial thermal weight loss temperature T

[0298] It should be noted that the present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and embodiments having substantially the same configuration and playing the same role and effects as the technical idea within the scope of the technical solutions of the present disclosure are all included within the technical scope of the present disclosure. Furthermore, within the scope of the main idea of the present disclosure, various modifications that can be thought of by those skilled in the art, and other modes constructed by combining part of the components of the embodiments, are also included within the scope of the present disclosure.

Claims

1. An isolation membrane comprising a porous base membrane and a porous coating on at least one side of the porous base membrane, wherein, The porous coating comprises silicon-containing organic resin particles having an initial thermal weight loss temperature T 3d of 290°C to 330°C.

2. The separator film according to claim 1, wherein The initial thermal weight loss temperature T of the silicon-containing organic resin particles 3d is 300°C to 330°C.

3. The separator according to claim 1 or 2, wherein the silicon-containing organic resin particles have no melting point; and / or the silicon-containing organic resin particles have no glass transition temperature below 300°C.

4. The separator according to any one of claims 1 to 3, wherein the silicon-containing organic resin particles have a dissolution rate of 3% or less when immersed in a mixed solvent of ethylene carbonate and methyl ethyl carbonate at a volume ratio of 3:7 at 60°C for 7 days; and / or the silicon-containing organic resin particles have a swelling degree of 3% or less when immersed in a mixed solvent of ethylene carbonate and methyl ethyl carbonate at a volume ratio of 3:7 at 60°C for 7 days; and / or the silicon-containing organic resin particles have no oxidation peak in a cyclic voltammogram for the first cycle in a voltage range of 2.50 V to 4.45 V.

5. The separator according to any one of claims 1 to 4, wherein The true density of the silicon-containing organic resin particles is 1.1 g / cm 3 -1.4 g / cm 3 ; and / or, the silicon-containing organic resin particles include agglomerates of primary particles; and / or the silicon-containing organic resin particles have a volume distribution particle size Dv50 of 300 nm to 800 nm.

6. The separator film according to claim 5, wherein the primary particles in the agglomerates have a particle size of 30 nm to 250 nm.

7. The separator film according to any one of claims 1 to 6, wherein the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic resin particles contain carbon-carbon bonds and siloxane structures.

8. The separator film according to any one of claims 1 to 7, wherein the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic resin particles are network structures formed with carbon-carbon bonds as a main chain, and side chains containing siloxane structures.

9. The separator film according to any one of claims 1 to 8, wherein the silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic crosslinked resin particles include crosslinking structure units, optionally, the crosslinking structure units include one or more of divinylbenzene structure units, diethylene glycol divinyl ether structure units, triethylene glycol divinyl ether structure units, diallyl maleate structure units, ethylene glycol dimethacrylate structure units, 1,4-butanediol diacrylate structure units, 1,6-hexanediol diacrylate structure units, 1,8-octanediol diacrylate structure units, trimethylolpropane triacrylate structure units, pentaerythritol trimethacrylate structure units, tetraethylene glycol dimethacrylate structure units, tripropylene glycol diacrylate structure units, 2,2,4-trimethyladipoyl bis[2-ethylaziridine] structure units, 1,1-sebacoyl bis[2-methylaziridine] structure units, 1,1-(1,3-phenylenedicarbonyl) bis[2-methylaziridine] structure units, trimethylolpropane tris(2-methyl-1-aziridinyl propionate) structure units, trimethylolpropane-tris[3-(2-methylaziridinyl)propionate] structure units, pentaerythritol tri(3-aziridinyl) propionate structure units.

10. The separator according to any one of claims 1 to 9, wherein the mass content of the silicon-containing organic resin particles in the porous coating layer is 50% to 99% based on the total mass of the porous coating layer; and / or the thickness of the porous coating layer is 0.5 μm to 5 μm.

11. The separator according to any one of claims 1 to 10, wherein The isolation film has a longitudinal heat shrinkage rate of less than or equal to 1.5% when heated at 130°C for 1 hour; and / or, The isolation film has a transverse heat shrinkage rate of less than or equal to 1.5% when heated at 130°C for 1 hour.

12. A silicon-containing organic resin particle, wherein, The initial thermal weight loss temperature T of the silicon-containing organic resin particles 3d is 290°C to 330°C.

13. The silicon-containing organic resin particles according to claim 12, wherein, The initial thermal weight loss temperature T of the silicon-containing organic resin particles 3d is 300°C to 330°C.

14. The silicon-containing organic resin particles according to claim 12 or 13, wherein, The silicon-containing organic resin particles have no melting point; and / or, The silicon-containing organic resin particles have no glass transition temperature below 300°C.

15. The silicon-containing organic resin particles according to any one of claims 12 to 14, wherein, The silicon-containing organic resin particles have a dissolution rate of less than or equal to 3% when soaked in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at 60°C for 7 days; and / or, The silicon-containing organic resin particles have a swelling degree of less than or equal to 3% when soaked in a mixed solvent of ethylene carbonate and methyl ethyl carbonate in a volume ratio of 3:7 at 60°C for 7 days; and / or, The silicon-containing organic resin particles have no oxidation peak in a voltage range of 2.50V to 4.45V in a cyclic voltammogram of the first cycle.

16. The silicon-containing organic resin particles according to any one of claims 12 to 15, wherein, The true density of the silicon-containing organic resin particles is 1.1 g / cm 3 -1.4 g / cm 3 ; and / or, The silicon-containing organic resin particles comprise agglomerates of primary particles; and / or, The silicon-containing organic resin particles have a volume distribution particle size Dv50 of 300nm to 800nm.

17. The silicon-containing organic resin particles according to claim 16, wherein, The primary particles in the agglomerates have a particle size of 30nm to 250nm.

18. The silicon-containing organic resin particles according to any one of claims 12-17, wherein, The silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic resin particles contain carbon-carbon bonds and siloxane structures.

19. The silicon-containing organic resin particles according to any one of claims 12-18, wherein, The silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic resin particles are network structures formed with carbon-carbon bonds as the main chain, and side chains containing siloxane structures.

20. The silicon-containing organic resin particles according to any one of claims 12-19, wherein, The silicon-containing organic resin particles are silicon-containing organic crosslinked resin particles, and the silicon-containing organic crosslinked resin particles comprise crosslinking structure units, Optionally, the crosslinking structure units comprise one or more of divinylbenzene structure units, diethylene glycol divinyl ether structure units, triethylene glycol divinyl ether structure units, diallyl maleate structure units, ethylene glycol dimethacrylate structure units, 1,4-butanediol diacrylate structure units, 1,6-hexanediol diacrylate structure units, 1,8-octanediol diacrylate structure units, trimethylolpropane triacrylate structure units, pentaerythritol trimethacrylate structure units, tetraethylene glycol dimethacrylate structure units, tripropylene glycol diacrylate structure units, 2,2,4-trimethylhexanedioyl bis[2-ethylaziridine] structure units, 1,1-nonanedioyl bis[2-methylaziridine] structure units, 1,1-(1,3-phenylenedicarbonyl)bis[2-methylaziridine] structure units, trimethylolpropane tris(2-methyl-1-aziridinyl propionate) structure units, trimethylolpropane-tris[3-(2-methylaziridinyl)propionate] structure units, pentaerythritol tris(3-aziridinyl)propionate structure units.

21. A method for preparing silicon-containing organic resin particles, comprising the steps of: providing a pre-emulsion comprising monomers, a crosslinking agent, an emulsifier, an initiator, water, the monomers comprising a silane coupling agent comprising an alkenyl group and / or an acryloxy group; performing an emulsion polymerization reaction under heating, inert gas protection, and stirring conditions; drying the product of the emulsion polymerization reaction; and then performing a baking process under an inert gas atmosphere, followed by a crushing process and a grinding process to obtain the silicon-containing organic resin particles.

22. The method of claim 21, wherein the temperature at which the product of the emulsion polymerization reaction is dried is 80°C to 150°C; and / or the time for which the product of the emulsion polymerization reaction is dried is 2h to 12h.

23. The method of claim 21 or 22, wherein the drying of the product of the emulsion polymerization reaction is performed by vacuum drying, spray drying, air blowing drying, microwave drying, or fluidized bed drying.

24. The method of any one of claims 21 to 23, wherein the temperature of the baking process is 160°C to 250°C; and / or the time of the baking process is 1h to 8h.

23. The method of claim 21 or 22, wherein, 25. The method of any one of claims 21 to 24, wherein the grinding process comprises the steps of: mixing the material from the crushing process with a solvent, a grinding medium, and optionally a dispersant to obtain a mixed slurry, and then performing a grinding process on the mixed slurry to obtain the silicon-containing organic resin particles.

26. The method of claim 25, wherein the grinding process satisfies at least one of the following conditions (1) to (6): (1) the solvent comprises one or more of water, methanol, and ethanol; (2) the dispersant comprises one or more of a polyacrylic acid type dispersant, a carboxymethyl cellulose type dispersant, polyethylene glycol, polyvinyl alcohol, and polyvinylpyrrolidone; 25. The method of any one of claims 21-24, wherein, (3) the grinding medium comprises one or more of zirconia balls, alumina balls, and silicon nitride balls; 26. The method of claim 25, wherein, (4) the average particle size of the grinding medium is 0.1mm to 2mm; (5) the filling rate of the grinding medium is 30% to 80%; and / or (6) the rotation speed of the grinding is 500rpm to 3000rpm.

27. The method of any one of claims 21 to 26, wherein the heating temperature of the maturation stage of the emulsion polymerization reaction is 70°C to 95°C; and / or the heating time of the maturation stage of the emulsion polymerization reaction is 1h to 5h; and / or the inert gas comprises one or more of nitrogen, argon, and helium.

28. The method of any one of claims 21 to 27, wherein the emulsion polymerization reaction comprises the steps of: dropping the pre-emulsion into a reactor containing water under a first temperature, inert gas protection, and stirring conditions, and then increasing the temperature to the heating temperature of the maturation stage to perform a maturation reaction for a first time to obtain the silicon-containing organic resin particles.

29. The method of claim 28, wherein the first temperature is 55°C to 70°C; and / or the first time is 3h to 6h.

30. The method of any one of claims 21 to 29, wherein the pre-emulsion is prepared by the steps of: mixing the monomers, the crosslinking agent, the emulsifier, and the initiator to obtain a mixture, and then performing a homogenization process on the mixture under heating, inert gas protection, and stirring conditions to obtain the pre-emulsion. ​ ​ ​ ​ 28. The method of any one of claims 21-27, wherein, ​ 29. The method of claim 28, wherein, ​ ​ one or more of gamma-methacryloxypropyl tris(trimethylsiloxy)silane, (3-acryloyloxypropyl)tris(trimethylsiloxy)silane, 3-methacryloxypropyltrimethoxysilane, acryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, acryloxypropyltriethoxysilane, gamma-methacryloxypropyltriisopropoxysilane, 3-(acryloxy)propyltrimethoxysilane, 3-methacryloxypropyltris(methoxyethoxy)silane, vinyltrimethoxysilane, 7-octenyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, tri-t-butoxyvinylsilane, vinyltris(beta-methoxyethoxy)silane, ethylene tris[(1-methylethenyl)oxy]silane, vinyltris-t-butylperoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxysilane, (3-acryloxy)dimethylmethoxysilane, 3-methacryloxypropyldimethylethoxysilane, diethylmethylvinylsilane, vinyl dimethyl ethoxysilane, methylvinyl diethoxysilane, vinylmethyl dimethoxysilane, vinylmethyl diethoxysilane, methylvinyl dimethoxysilane, 3-(methacryloxy)propylmethyldiethoxysilane; and / or, one or more of divinylbenzene, diethylene glycol divinyl ether, triethylene glycol divinyl ether, diallyl maleate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,8-octanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol trimethacrylate, tetraethylene glycol dimethacrylate, tripropylene glycol diacrylate, 2,2,4-trimethylhexanedioic acid bis[2-ethylaziridine], 1,1-nonanedioic acid bis[2-methylaziridine], 1,1-(1,3-phenylenedicarbonyl)bis[2-methylaziridine], trimethylolpropane tris(2-methyl-1-aziridinylpropionate), trimethylolpropane-tris[3-(2-methylaziridinyl)propionate], pentaerythritol tris(3-aziridinyl)propionate; and / or, a mass fraction of the crosslinking agent is 1.5% to 18% based on a total mass of the monomer and the crosslinking agent being 100%.

31. A dispersion liquid of silicon-containing organic resin particles, comprising the silicon-containing organic resin particles according to any one of claims 12 to 20 and a dispersant, or obtained by the method according to any one of claims 21 to 30.

32. A secondary battery cell comprising a positive electrode sheet, a negative electrode sheet, and the separator according to any one of claims 1 to 11, the separator being disposed between the positive electrode sheet and the negative electrode sheet.

33. A battery device comprising a plurality of the secondary battery cell according to claim 32.

34. An electric device comprising the secondary battery cell of claim 32 or the battery device of claim 33.

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