A method and system for preparing a surface-modified lithium battery separator

Abstract

This invention relates to the field of lithium-ion battery separator fabrication technology, and discloses a method and system for fabricating lithium-ion battery separators based on surface modification. The method includes: selecting a set of original glass fiber types based on the battery electrolyte to obtain a candidate glass fiber type set; acquiring multiple separator test datasets based on the candidate glass fiber type set and the candidate polymer fiber type set; obtaining separator fabrication data based on the multiple separator test datasets; performing wet web forming based on the separator fabrication data to obtain a target nonwoven fabric substrate; coating the target nonwoven fabric substrate with ceramic particles and a polymer binder to obtain a modified nonwoven fabric substrate; and heat-setting the modified nonwoven fabric substrate to obtain a composite nonwoven separator. This invention can improve the cycle life and thermal stability of lithium-ion battery separators and reduce the risk of performance degradation.

Description

Technical Field

[0001] This invention relates to the field of lithium battery separator preparation technology, and in particular to a method and system for preparing lithium battery separators based on surface modification. Background Technology

[0002] Lithium-ion battery separators are indispensable key components in batteries. Their core function is to physically isolate the positive and negative electrodes to prevent internal short circuits, while allowing lithium ions in the electrolyte to pass freely for charging and discharging. The performance of the separator, including its mechanical strength, pore structure, thermal stability, and compatibility with the electrolyte, directly determines the overall safety, energy density, and long-term cycle life of the battery. Therefore, developing high-performance lithium-ion battery separators is of paramount importance for improving battery reliability and efficiency.

[0003] Traditional technologies typically employ a one-time wet web formation and simple coating process to prepare the diaphragm. However, traditional methods suffer from drawbacks such as uneven fiber dispersion leading to insufficient mechanical strength of the diaphragm, poor compatibility with electrolyte causing chemical degradation, and low thermal stability increasing the risk of short circuits. Summary of the Invention

[0004] This invention provides a method for preparing a lithium battery separator based on surface modification and a computer-readable storage medium. Its main purpose is to improve the cycle life and thermal stability of the lithium battery separator and reduce the risk of performance degradation.

[0005] To achieve the above objectives, the present invention provides a method for preparing a lithium battery separator based on surface modification, comprising:

[0006] Receive the membrane preparation instruction, and determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction. The original glass fiber type set includes multiple original glass fiber types.

[0007] Based on the battery electrolyte, the original set of glass fiber types is selected to obtain a set of candidate glass fiber types;

[0008] A candidate set of polymer fiber types is set up, and membrane preparation tests are performed based on the candidate set of glass fiber types and the candidate set of polymer fiber types to obtain multiple membrane test datasets. The membrane test datasets include multiple membrane test data.

[0009] Response surface methodology was used to optimize the membrane preparation data based on multiple membrane test datasets. The membrane preparation data included: target glass fiber type, target polymer fiber type, and target glass fiber content.

[0010] Based on the diaphragm preparation data, wet web forming was performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate was then subjected to plasma treatment to obtain the target nonwoven fabric substrate.

[0011] Ceramic particles and polymer adhesives are obtained, and the target nonwoven fabric substrate is coated with ceramic particles and polymer adhesives to obtain a modified nonwoven fabric substrate, wherein the modified nonwoven fabric substrate includes a ceramic polymer functional coating.

[0012] The modified nonwoven fabric substrate is heat-set to obtain a composite nonwoven membrane. Based on the composite nonwoven membrane, a surface-modified lithium battery membrane is prepared.

[0013] Optionally, the selection of candidate glass fiber types based on the battery electrolyte from the original set of glass fiber types includes:

[0014] The original glass fiber types are extracted sequentially from the original glass fiber type set, and the original glass fiber samples are obtained based on the extracted original glass fiber types.

[0015] The original glass fiber samples were subjected to benchmark performance data collection to obtain a benchmark fiber performance set, which includes benchmark fiber strength and benchmark fiber mass.

[0016] The original glass fiber sample was immersed in battery electrolyte to test its stability, and the immersed glass fiber sample was obtained.

[0017] The immersion performance of the glass fiber samples was collected to obtain the immersion fiber performance group, which includes: immersion fiber strength and immersion fiber mass.

[0018] The performance retention rate group was calculated based on the baseline fiber performance group and the soaked fiber performance group. The chemical stability was obtained by summing the performance retention rate groups.

[0019] By summarizing the chemical stability data, a chemical stability set is obtained. Based on the preset chemical stability ratio and the chemical stability set, a candidate glass fiber type set is determined from the original glass fiber type set.

[0020] Optionally, the membrane preparation test is performed based on the candidate glass fiber type set and the candidate polymer fiber type set to obtain multiple membrane test datasets, including:

[0021] A set of reinforcing material components is constructed based on a set of candidate glass fiber types and a set of candidate polymer fiber types. The set of reinforcing material components includes multiple reinforcing material components, and each reinforcing material component contains one candidate glass fiber type and one candidate polymer fiber type.

[0022] For each reinforcing material component in the reinforcing material component set, the following operation is performed:

[0023] Set a glass fiber content range, test the reinforcing material components based on the glass fiber content range, and obtain the diaphragm test dataset;

[0024] By summing up the membrane test datasets corresponding to each reinforcing material component, multiple membrane test datasets are obtained.

[0025] Optionally, the test of the reinforcing material composition based on the glass fiber content range to obtain the diaphragm test dataset includes:

[0026] The glass fiber content range is divided to obtain the test glass fiber content set;

[0027] A set of test nonwoven membranes is prepared based on the set of test glass fiber content and the composition of reinforcing materials. The set of test nonwoven membranes includes multiple test nonwoven membranes, and each test nonwoven membrane corresponds to a test glass fiber content.

[0028] Composite membrane tests were performed on each nonwoven membrane in the test nonwoven membrane set to obtain the test battery cycle life set, which includes the cycle life of multiple test batteries.

[0029] The test battery cycle life set is matched with the test glass fiber content set to obtain the separator test dataset. The separator test dataset includes multiple separator test data, and each separator test data contains a test battery cycle life and a test glass fiber content.

[0030] By summing up the membrane test datasets corresponding to each reinforcing material component, multiple membrane test datasets are obtained.

[0031] Optionally, the composite separator test is performed on each nonwoven separator in the test nonwoven separator set to obtain the test battery cycle life set, including:

[0032] The following procedure was performed on each test nonwoven membrane in the test nonwoven membrane set:

[0033] The mechanical properties of the nonwoven membrane were tested using a pre-constructed mechanical testing device to obtain the tensile strength and puncture strength. The mechanical testing device included a tensile testing machine and a puncture testing machine.

[0034] Based on the test of nonwoven membrane, a porosity test sample was obtained, and the porosity of the porosity test sample was detected to obtain the test porosity.

[0035] Thermogravimetric analysis was performed on the tested nonwoven membrane to obtain its thermal stability.

[0036] The tensile strength, puncture strength, porosity, and thermal stability of the diaphragm were combined to obtain the diaphragm test performance group;

[0037] The cycle life of the test battery was calculated based on the diaphragm test performance group.

[0038] The cycle life of the test battery corresponding to each test nonwoven separator is summarized to obtain the test battery cycle life set.

[0039] Optionally, the step of performing porosity detection on the porosity test sample to obtain the test porosity includes:

[0040] Collect the sample mass and density of the porosity test sample;

[0041] The porosity test sample is immersed in the pre-obtained n-butanol reagent to obtain the wetting test sample;

[0042] The mass of the wetting test sample is measured, and the test porosity is calculated based on the mass of the wetting sample, the mass of the test sample, and the density of the test sample. The test porosity is expressed as:

[0043] ;

[0044] in, Indicates the test porosity. Indicates the quality of the test sample. Indicates the quality of the impregnated sample. Indicates the density of the test sample. This indicates the preset n-butanol density.

[0045] Optionally, calculating the cycle life of the test battery based on the separator test performance group includes:

[0046] Construct a battery cycle life correlation table, which includes multiple battery cycle life correlation data, and each battery cycle life correlation data includes: battery cycle life and associated separator performance group;

[0047] Perform the following operations on each battery life-related data in the battery cycle life association table:

[0048] Calculate the performance similarity based on the membrane test performance group and the associated membrane performance group in the battery life correlation data;

[0049] Summarize the performance similarity scores to obtain a performance similarity set, and identify the maximum similarity score within the performance similarity set;

[0050] The battery life correlation data corresponding to the highest similarity is recorded as the most similar correlation data, and the test battery cycle life is extracted from the most similar correlation data.

[0051] Optionally, the wet web forming based on diaphragm preparation data to obtain the composite nonwoven fabric substrate includes:

[0052] The target glass fiber raw material and the target polymer fiber raw material are obtained based on the target glass fiber type, target polymer fiber type and target glass fiber content in the membrane preparation data.

[0053] Based on the preset first dispersion concentration, the target glass fiber raw material and the target polymer fiber raw material are added to the pre-obtained deionized water to obtain mixed fibers;

[0054] Obtain a dispersant, add the dispersant to the mixed fibers, and pre-dissolve the mixed fibers after adding the dispersant according to the preset first dissolution intensity to obtain a preliminary dissolved fiber cluster;

[0055] Based on the preset second dispersion concentration, the initially disintegrated fiber clusters are diluted with water to obtain diluted disintegrated fiber clusters;

[0056] The diluted and disintegrated fiber clusters are subjected to high-intensity disintegration according to the preset second disintegration intensity to obtain the target fiber slurry.

[0057] The target fiber slurry is injected into a pre-constructed fiber generator to obtain a raw fiber wet web, and the raw fiber wet web is compacted to obtain a compacted fiber wet web.

[0058] The compacted fiber wet web is dried using a pre-designed blower drying oven to obtain a dried nonwoven fabric substrate;

[0059] Obtain the bonding fiber, and set the hot pressing temperature based on the bonding fiber, the target glass fiber raw material, and the target polymer fiber raw material;

[0060] A composite nonwoven fabric substrate is obtained by hot pressing a dry nonwoven fabric substrate using a hot pressing setting temperature, a pre-constructed hot press, and bonding fibers.

[0061] Optionally, setting the hot pressing temperature based on the bonding fiber, the target glass fiber raw material, and the target polymer fiber raw material includes:

[0062] The glass fiber decomposition temperature of the target glass fiber raw material and the polymer fiber decomposition temperature of the target polymer fiber raw material were obtained respectively.

[0063] Find the melting point temperature of the bonding fiber;

[0064] The hot pressing temperature range is constructed based on the melting point temperature of the bonding fiber, the decomposition temperature of the glass fiber, and the decomposition temperature of the polymer fiber.

[0065] The hot-pressing temperature range is divided to obtain multiple test hot-pressing temperatures;

[0066] The test hot-pressing temperature is extracted sequentially from multiple test hot-pressing temperatures, and the substrate is prepared based on the extracted test hot-pressing temperature to obtain the test nonwoven fabric substrate;

[0067] The strength of the nonwoven fabric substrate was tested to obtain the substrate strength.

[0068] By summing the strengths of the substrates, multiple substrate strengths are obtained.

[0069] The strength curves of multiple substrates are obtained by curve fitting based on multiple hot-pressing temperatures.

[0070] The hot pressing and shaping temperature is selected based on the substrate strength curve.

[0071] To achieve the above objectives, the present invention also provides a surface-modified lithium battery separator preparation system, comprising:

[0072] The glass fiber acquisition module is used to receive the membrane preparation instruction, determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction, wherein the original glass fiber type set includes multiple original glass fiber types, and selects the original glass fiber type set based on the battery electrolyte to obtain the candidate glass fiber type set;

[0073] The test data construction module is used to set up a candidate polymer fiber type set, and to conduct membrane preparation tests based on the candidate glass fiber type set and the candidate polymer fiber type set to obtain multiple membrane test datasets. The membrane test datasets include multiple membrane test data.

[0074] The nonwoven fabric substrate preparation module is used to perform response surface methodology optimization based on multiple diaphragm test datasets to obtain diaphragm preparation data. The diaphragm preparation data includes: target glass fiber type, target polymer fiber type, and target glass fiber content. Based on the diaphragm preparation data, wet web forming is performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate is then subjected to plasma treatment to obtain the target nonwoven fabric substrate.

[0075] A composite diaphragm shaping module is used to obtain ceramic particles and polymer adhesives, and to coat the target nonwoven fabric substrate with the ceramic particles and polymer adhesives to obtain a modified nonwoven fabric substrate. The modified nonwoven fabric substrate includes a ceramic polymer functional coating. The modified nonwoven fabric substrate is then heat-shaped to obtain a composite nonwoven fabric diaphragm.

[0076] To address the above problems, the present invention also provides an electronic device, the electronic device comprising:

[0077] Memory, storing at least one instruction;

[0078] The processor executes the instructions stored in the memory to implement the above-described method for preparing a lithium battery separator based on surface modification.

[0079] To address the aforementioned problems, the present invention also provides a computer-readable storage medium storing at least one instruction, which is executed by a processor in an electronic device to implement the above-described method for preparing a lithium battery separator based on surface modification.

[0080] To address the problems described in the background art, this invention first selects a set of candidate glass fiber types based on the battery electrolyte. This step, through chemical stability testing and selection, ensures the compatibility of the candidate glass fiber types with the electrolyte. Next, membrane preparation tests are conducted based on the candidate glass fiber type set and the candidate polymer fiber type set, resulting in multiple membrane test datasets. This step, by systematically constructing a set of reinforcing material components and conducting membrane preparation tests, comprehensively evaluates the impact of different combinations of glass fibers and polymer fibers on battery cycle life. Compared to existing technologies that rely on empirical selection, this method uses a data-driven approach to optimize fiber ratios, improving the accuracy of membrane performance prediction and preparation efficiency. Then, this scheme optimizes multiple membrane test datasets using response surface methodology to obtain membrane preparation data. This step, utilizing response surface methodology to optimize multiple membrane test datasets, can quickly and accurately find the optimal combination of membrane preparation parameters. Compared to traditional trial-and-error methods, this method reduces experimental complexity through mathematical models and enhances the scientific rigor and reliability of separator performance optimization. Furthermore, based on separator preparation data, wet web forming is performed to obtain a composite nonwoven fabric substrate. This substrate is then subjected to plasma treatment to obtain the target nonwoven fabric substrate. This step employs a staged wet web forming and plasma treatment process. The staged loosening strategy, through pre-loosening followed by high-intensity loosening, improves fiber dispersion uniformity and reduces energy consumption. Plasma treatment enhances the surface activity of the substrate. Compared to the fiber damage that may result from a single high-intensity loosening in existing technologies, this method improves preparation efficiency and quality consistency while ensuring substrate strength. Finally, ceramic particles and polymer binders are obtained and used to coat the target nonwoven fabric substrate, resulting in a modified nonwoven fabric substrate. This step, by coating with ceramic particles and polymer binders to form a functional coating, endows the separator with excellent thermal stability and mechanical strength. Therefore, this invention can improve the cycle life and thermal stability of lithium battery separators and reduce the risk of performance degradation. Attached Figure Description

[0081] Figure 1 This is a schematic flowchart of a method for preparing a surface-modified lithium battery separator according to an embodiment of the present invention.

[0082] Figure 2This is a functional block diagram of a surface-modified lithium battery separator fabrication system provided in an embodiment of the present invention;

[0083] Figure 3 This is a schematic diagram of the structure of an electronic device that implements the surface-modified lithium battery separator preparation method according to an embodiment of the present invention.

[0084] Explanation of reference numerals in the attached figures:

[0085] 10. Electronic device; 11. Processor; 12. Memory; 13. Bus.

[0086] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0087] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0088] This application provides a method for preparing a lithium-ion battery separator based on surface modification. The execution entity of the surface-modified lithium-ion battery separator preparation method includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the method provided in this application: a server, a terminal, etc. In other words, the surface-modified lithium-ion battery separator preparation method can be executed by software or hardware installed on a terminal device or a server device, and the software can be a blockchain platform. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster.

[0089] Reference Figure 1 The diagram shown is a schematic flow chart of a surface-modified lithium battery separator preparation method according to an embodiment of the present invention. In this embodiment, the surface-modified lithium battery separator preparation method includes:

[0090] S1. Receive the membrane preparation instruction, and determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction. The original glass fiber type set includes multiple original glass fiber types.

[0091] Understandably, the membrane preparation instruction refers to a manually initiated instruction to prepare the membrane. The original glass fiber type set refers to the collection of various glass fiber types included in the membrane preparation instruction that can be used for membrane preparation, such as electronic-grade glass fiber, high-strength glass fiber, and low-dielectric glass fiber. The battery electrolyte refers to the electrolyte included in the membrane preparation instruction and used in the subsequent battery, such as lithium hexafluorophosphate / ethylene carbonate, diethyl carbonate, and dimethyl carbonate.

[0092] S2. Based on the battery electrolyte, select the original glass fiber type set to obtain the candidate glass fiber type set.

[0093] It is clear that the candidate glass fiber type set refers to a collection of multiple original glass fiber types that have high chemical stability in the battery electrolyte after selection.

[0094] In detail, the selection of the original glass fiber type set based on the battery electrolyte to obtain the candidate glass fiber type set includes:

[0095] The original glass fiber types are extracted sequentially from the original glass fiber type set, and the original glass fiber samples are obtained based on the extracted original glass fiber types.

[0096] The original glass fiber samples were subjected to benchmark performance data collection to obtain a benchmark fiber performance set, which includes benchmark fiber strength and benchmark fiber mass.

[0097] The original glass fiber sample was immersed in battery electrolyte to test its stability, and the immersed glass fiber sample was obtained.

[0098] The immersion performance of the glass fiber samples was collected to obtain the immersion fiber performance group, which includes: immersion fiber strength and immersion fiber mass.

[0099] The performance retention rate group was calculated based on the baseline fiber performance group and the soaked fiber performance group. The chemical stability was obtained by summing the performance retention rate groups.

[0100] By summarizing the chemical stability data, a chemical stability set is obtained. Based on the preset chemical stability ratio and the chemical stability set, a candidate glass fiber type set is determined from the original glass fiber type set.

[0101] It should be explained that the "original glass fiber sample" refers to the physical fiber material obtained from the extracted original glass fiber type and used for subsequent benchmark and immersion tests. The "benchmark fiber performance set" refers to the set of parameters representing the performance of the original glass fiber sample, where the benchmark fiber strength refers to the maximum tensile strength of the original glass fiber sample, and the benchmark fiber mass refers to the mass of the original glass fiber sample. The "immersion glass fiber sample" refers to the original glass fiber sample after undergoing an immersion stability test. The immersion stability test using battery electrolyte involves immersing the original glass fiber sample in a battery electrolyte environment at a specific temperature (e.g., 60°C) for a preset time (e.g., 72 hours) to simulate the long-term operating conditions of a battery. This immersion stability test can evaluate the chemical stability of the original glass fiber type in the battery electrolyte, thereby screening out original glass fiber types with good compatibility with the battery electrolyte. The "immersion fiber performance set" refers to the set of parameters representing the performance of the immersion glass fiber sample, where the immersion fiber strength refers to the maximum tensile strength of the immersion glass fiber sample, and the immersion fiber mass refers to the mass of the immersion glass fiber sample.

[0102] Furthermore, the performance retention rate group refers to a set of multiple performance retention rates. The performance retention rate indicates the degree to which a certain property of the original glass fiber sample is damaged after immersion in the battery electrolyte. A higher performance retention rate indicates a smaller degree of damage to the corresponding property. The performance retention rate is calculated by dividing the immersion fiber property by the corresponding baseline fiber property; for example, the strength retention rate is the ratio of the immersion fiber strength to the baseline fiber strength. The chemical stability refers to the overall stability of the candidate glass fiber type in the battery electrolyte, which is the sum of all performance retention rates in the performance retention rate group. The chemical stability ratio is a manually set proportional constant, for example, 20%. The step of determining the candidate glass fiber type set in the original glass fiber type set according to the preset chemical stability ratio and chemical stability set refers to: numerically sorting the chemical stability set to obtain a chemical stability sequence, wherein the larger the chemical stability value, the higher it is ranked in the chemical stability sequence; then selecting multiple candidate stability values ​​that are ranked in the first 'a' in the chemical stability sequence, where 'a' represents the product of the chemical stability ratio and the total number of original glass fiber types; and then recording the set of original glass fiber types corresponding to multiple candidate stability values ​​as the candidate glass fiber type set.

[0103] S3. Set up a candidate polymer fiber type set, and conduct membrane preparation tests based on the candidate glass fiber type set and the candidate polymer fiber type set to obtain multiple membrane test datasets. The membrane test datasets include multiple membrane test data.

[0104] It is clear that the candidate polymer fiber type set refers to a collection of multiple candidate polymer fiber types. These candidate polymer fiber types refer to types of polymer fibers that can be used in subsequent diaphragm preparation, such as: polyethylene, polypropylene, polyimide, polyetheretherketone, polyurethane, polyacrylonitrile, polylactic acid, and other organic polymers commonly used in nonwoven fabric systems. The diaphragm test dataset refers to a collection of multiple diaphragm test data obtained after diaphragm preparation and testing.

[0105] In detail, the membrane preparation test is performed based on the candidate glass fiber type set and the candidate polymer fiber type set to obtain multiple membrane test datasets, including:

[0106] A set of reinforcing material components is constructed based on a set of candidate glass fiber types and a set of candidate polymer fiber types. The set of reinforcing material components includes multiple reinforcing material components, and each reinforcing material component contains one candidate glass fiber type and one candidate polymer fiber type.

[0107] For each reinforcing material component in the reinforcing material component set, the following operation is performed:

[0108] Set a glass fiber content range, test the reinforcing material components based on the glass fiber content range, and obtain the diaphragm test dataset;

[0109] By summing up the membrane test datasets corresponding to each reinforcing material component, multiple membrane test datasets are obtained.

[0110] Understandably, the reinforcing material component set refers to a collection of multiple reinforcing material components. Each reinforcing material component is a set composed of a candidate glass fiber type and a candidate polymer fiber type. This reinforcing material component set is constructed by pairing the candidate glass fiber type set and the candidate polymer fiber type set one by one to obtain multiple reinforcing material components. For example, if the candidate glass fiber type set is {A1, A2} and the candidate polymer fiber type set is {B1, B2}, then the reinforcing material component set contains the following multiple reinforcing material components: {A1, B1}, {A1, B2}, {A2, B1}, and {A2, B2}. The glass fiber content range refers to the artificially set mass ratio of glass fiber to the raw materials used in the subsequent membrane preparation (e.g., the mass ratio of the target glass fiber raw material to the total mass of the target glass fiber raw material and the target polymer fiber raw material). This glass fiber content range can be set based on previous preparation experience.

[0111] Specifically, the test of the reinforcing material composition based on the glass fiber content range to obtain the diaphragm test dataset includes:

[0112] The glass fiber content range is divided to obtain the test glass fiber content set;

[0113] A set of test nonwoven membranes is prepared based on the set of test glass fiber content and the composition of reinforcing materials. The set of test nonwoven membranes includes multiple test nonwoven membranes, and each test nonwoven membrane corresponds to a test glass fiber content.

[0114] Composite membrane tests were performed on each nonwoven membrane in the test nonwoven membrane set to obtain the test battery cycle life set, which includes the cycle life of multiple test batteries.

[0115] The test battery cycle life set is matched with the test glass fiber content set to obtain the separator test dataset. The separator test dataset includes multiple separator test data, and each separator test data contains a test battery cycle life and a test glass fiber content.

[0116] By summing up the membrane test datasets corresponding to each reinforcing material component, multiple membrane test datasets are obtained.

[0117] It should be explained that the "test glass fiber content set" refers to a collection of multiple test glass fiber contents obtained by dividing the glass fiber content range. Dividing the glass fiber content range means selecting multiple discrete content values ​​within a preset glass fiber content range using experimental design methods such as equidistant sampling, Latin hypercube sampling, or uniform design. These discrete content values ​​are the test glass fiber contents. The "test nonwoven fabric separator set" refers to a collection of multiple test nonwoven fabric separators. The test nonwoven fabric separator refers to a nonwoven fabric separator prepared according to a specific test glass fiber content and reinforcing material composition. The preparation method of this test nonwoven fabric separator is the same as that of the subsequent composite nonwoven fabric separator, and will not be repeated here. The "test battery cycle life set" refers to the collection of cycle lives of separator batteries prepared from all the test nonwoven fabric separators in the test nonwoven fabric separator set. The separator battery refers to a test battery assembled using the test nonwoven fabric separator as the battery separator. The matching of the test battery cycle life set with the test glass fiber content set means that the test battery cycle life is combined with the corresponding test glass fiber content, and the resulting data set is a separator test data set. The set of separator test data corresponding to all test battery cycle life is the separator test dataset.

[0118] In detail, the composite separator test is performed on each nonwoven separator in the test nonwoven separator set to obtain the test battery cycle life set, including:

[0119] The following procedure was performed on each test nonwoven membrane in the test nonwoven membrane set:

[0120] The mechanical properties of the nonwoven membrane were tested using a pre-constructed mechanical testing device to obtain the tensile strength and puncture strength. The mechanical testing device included a tensile testing machine and a puncture testing machine.

[0121] Based on the test of nonwoven membrane, a porosity test sample was obtained, and the porosity of the porosity test sample was detected to obtain the test porosity.

[0122] Thermogravimetric analysis was performed on the tested nonwoven membrane to obtain its thermal stability.

[0123] The tensile strength, puncture strength, porosity, and thermal stability of the diaphragm were combined to obtain the diaphragm test performance group;

[0124] The cycle life of the test battery was calculated based on the diaphragm test performance group.

[0125] The cycle life of the test battery corresponding to each test nonwoven separator is summarized to obtain the test battery cycle life set.

[0126] Understandably, the mechanical testing device refers to equipment capable of testing the mechanical properties of the nonwoven membrane. Specifically, a tensile testing machine is an instrument used to measure the mechanical properties of the nonwoven membrane under axial tensile load, such as an electronic universal testing machine; a puncture testing machine is a specialized instrument used to measure the membrane's resistance to puncture by a sharp object, such as a spherical or needle-shaped puncture strength tester. The tensile strength test refers to the maximum tensile force of the nonwoven membrane obtained after mechanical property testing. This tensile strength is obtained by stretching the nonwoven membrane using a tensile testing machine; when the membrane breaks, the tensile force recorded by the tensile testing machine is recorded as the tensile strength test. The puncture strength test refers to the maximum force value of the nonwoven membrane resisting puncture damage obtained after mechanical property testing. This puncture strength test is obtained by puncturing the nonwoven membrane using a puncture testing machine; when the membrane is punctured, the maximum force value recorded by the puncture testing machine is recorded as the puncture strength test. The porosity test sample refers to the nonwoven fabric separator used for porosity detection. The test porosity refers to the percentage of pore volume within the test nonwoven fabric separator to its total volume. The separator's thermal stability refers to its ability to retain mass at high temperatures after thermogravimetric analysis (TGA). TGA involves measuring the mass change of the test nonwoven fabric separator with temperature under programmed temperature control (e.g., heating from room temperature to 600°C at a certain rate) and a specific atmosphere (e.g., nitrogen or air), thereby obtaining relevant thermal stability values ​​to characterize the separator's thermal stability. These relevant thermal stability values ​​include parameters such as thermal decomposition initiation temperature and maximum weight loss rate temperature. The specific method for obtaining the cycle life of the aforementioned test battery will be given in subsequent embodiments.

[0127] Specifically, the porosity detection of the porosity test sample to obtain the test porosity includes:

[0128] Collect the sample mass and density of the porosity test sample;

[0129] The porosity test sample is immersed in the pre-obtained n-butanol reagent to obtain the wetting test sample;

[0130] The mass of the wetting test sample is measured, and the test porosity is calculated based on the mass of the wetting sample, the mass of the test sample, and the density of the test sample. The test porosity is expressed as:

[0131] ;

[0132] in, Indicates the test porosity. Indicates the quality of the test sample. Indicates the quality of the impregnated sample. Indicates the density of the test sample. This indicates the preset n-butanol density.

[0133] Understandably, the test sample mass refers to the mass of the porosity test sample. The test sample density refers to the density of the porosity test sample. The n-butanol reagent refers to the organic solvent used to soak the porosity test sample to measure its porosity. The wetting test sample refers to the porosity test sample after wetting. The wetting sample mass refers to the mass of the wetting test sample. The principle of the above porosity measurement is as follows: after the porosity test sample is immersed in n-butanol, its internal pores will be completely filled by n-butanol. By measuring the change in mass of the porosity test sample before and after immersion (i.e., the change in mass before and after immersion), the porosity can be measured. The volume of n-butanol entering the pores of the porosity test sample can be calculated, and this volume is related to the total volume of the porosity test sample (i.e., The ratio of 1 / 2 to 1 / 2 is the test porosity.

[0134] In detail, the calculation of the test battery cycle life based on the separator test performance group includes:

[0135] Construct a battery cycle life correlation table, which includes multiple battery cycle life correlation data, and each battery cycle life correlation data includes: battery cycle life and associated separator performance group;

[0136] Perform the following operations on each battery life-related data in the battery cycle life association table:

[0137] Calculate the performance similarity based on the membrane test performance group and the associated membrane performance group in the battery life correlation data;

[0138] Summarize the performance similarity scores to obtain a performance similarity set, and identify the maximum similarity score within the performance similarity set;

[0139] The battery life correlation data corresponding to the highest similarity is recorded as the most similar correlation data, and the test battery cycle life is extracted from the most similar correlation data.

[0140] It should be explained that the battery cycle life correlation table refers to a data set composed of multiple battery cycle life correlation data, where each battery cycle life correlation data refers to a set of battery cycle life and a set of associated separator performance data. The battery cycle life correlation table is constructed as follows: Multiple historical batteries prepared in previous periods or under laboratory conditions are obtained. The battery cycle life of these historical batteries is queried, or the historical batteries are tested to obtain their cycle life. The testing involves repeatedly charging and discharging the historical battery under standard test conditions (e.g., constant temperature such as 25°C, specific charge / discharge rate such as 1C) until the discharge capacity of the historical battery decays to 80% of its initial capacity. The number of charge / discharge cycles completed at this point is the battery cycle life of the historical battery. The separator test performance group (i.e., associated separator performance group) of the battery separator used to prepare the historical battery is queried. The battery cycle life of the historical battery and the associated separator performance group are paired, and the resulting data set is one battery cycle life correlation data. This process is repeated to obtain multiple battery cycle life correlation data, thus forming the battery cycle life correlation table.

[0141] Furthermore, the performance similarity refers to the numerical value of the degree of similarity between the diaphragm test performance group and the associated diaphragm performance group, and the specific calculation method is as follows: ,in, Indicates performance similarity. This indicates the number of diaphragm test performance parameters in the diaphragm test performance group. Indicating the first in the diaphragm test performance group Each diaphragm was tested for performance. Indicates the first in the associated membrane performance group The performance of the associated membrane is defined as follows. The maximum similarity refers to the performance similarity with the highest numerical value within the set of performance similarities. Extracting the test battery cycle life from the most similar associated data means: recording the battery cycle life from the most similar associated data as the test battery cycle life.

[0142] S4. Response surface methodology optimization is performed based on multiple diaphragm test datasets to obtain diaphragm preparation data, which includes: target glass fiber type, target polymer fiber type, and target glass fiber content.

[0143] Furthermore, the steps of the response surface methodology optimization based on multiple separator test datasets are as follows: Different reinforcing material components and their corresponding glass fiber contents are used as independent variables, and the measured battery cycle life is used as the dependent variable (i.e., the response value). A multinomial model (such as a quadratic model) is used to fit the multiple separator test datasets, thereby constructing a mathematical model (i.e., the response surface) that describes the relationship between the independent and dependent variables. Then, by analyzing the contour plots and three-dimensional surface plots of this response surface, or by using mathematical optimization algorithms (such as the steepest descent method), the optimal parameter combination that maximizes the battery cycle life response value is found. This optimal parameter combination is the data combination of the target glass fiber type, the target polymer fiber type, and the target glass fiber content. Through the above response surface methodology optimization, candidate glass fiber types, candidate polymer fiber types, and test glass fiber contents with optimal test battery cycle life can be obtained (corresponding to the target glass fiber type, target polymer fiber type, and target glass fiber content, respectively).

[0144] S5. Based on the diaphragm preparation data, wet web forming is performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate is then subjected to plasma treatment to obtain the target nonwoven fabric substrate.

[0145] It is clear that the composite nonwoven fabric substrate refers to a base material with a three-dimensional network structure prepared based on diaphragm preparation data. The target nonwoven fabric substrate refers to the composite nonwoven fabric substrate after plasma treatment. Plasma treatment of the composite nonwoven fabric substrate refers to: placing the composite nonwoven fabric substrate in a plasma generator and treating it under a specific gas atmosphere (such as air, oxygen, nitrogen, or argon) and a specific power, using highly active particles in the plasma to physically bombard and chemically modify the surface of the substrate.

[0146] Specifically, the process of wet-laid fabrication based on diaphragm preparation data to obtain a composite nonwoven fabric substrate includes:

[0147] The target glass fiber raw material and the target polymer fiber raw material are obtained based on the target glass fiber type, target polymer fiber type and target glass fiber content in the membrane preparation data.

[0148] Based on the preset first dispersion concentration, the target glass fiber raw material and the target polymer fiber raw material are added to the pre-obtained deionized water to obtain mixed fibers;

[0149] Obtain a dispersant, add the dispersant to the mixed fibers, and pre-dissolve the mixed fibers after adding the dispersant according to the preset first dissolution intensity to obtain a preliminary dissolved fiber cluster;

[0150] Based on the preset second dispersion concentration, the initially disintegrated fiber clusters are diluted with water to obtain diluted disintegrated fiber clusters;

[0151] The diluted and disintegrated fiber clusters are subjected to high-intensity disintegration according to the preset second disintegration intensity to obtain the target fiber slurry.

[0152] The target fiber slurry is injected into a pre-constructed fiber generator to obtain a raw fiber wet web, and the raw fiber wet web is compacted to obtain a compacted fiber wet web.

[0153] The compacted fiber wet web is dried using a pre-designed blower drying oven to obtain a dried nonwoven fabric substrate;

[0154] Obtain the bonding fiber, and set the hot pressing temperature based on the bonding fiber, the target glass fiber raw material, and the target polymer fiber raw material;

[0155] A composite nonwoven fabric substrate is obtained by hot pressing a dry nonwoven fabric substrate using a hot pressing setting temperature, a pre-constructed hot press, and bonding fibers.

[0156] It is clear that the target glass fiber raw material refers to glass fiber composed of the target glass fiber type and having a content equal to the target glass fiber content. The target polymer fiber raw material refers to polymer fiber composed of the target polymer fiber type and having a content equal to the polymer content (1 minus the target glass fiber content). The first dispersion concentration and the second dispersion concentration refer to the percentage concentration (wt%) of the main fiber mass (i.e., the total mass of the target glass fiber raw material and the target polymer fiber raw material) in the fiber slurry (such as mixed fiber, diluted and disintegrated fiber clumps, etc.) to the total mass of the fiber slurry. Optionally, the first dispersion concentration and the second dispersion concentration are 2.0wt% and 0.5wt%, respectively. By setting different dispersion concentrations, the dispersion effect of the target glass fiber raw material and the target polymer fiber raw material can be optimized in stages. The first dispersion concentration is higher because: in the initial stage of dispersion, deionized water is used to ensure that the mixed fiber and the dispersant are in full contact, and large fiber clumps are initially broken up through pre-disintegration. Deionized water can avoid the interference of metal ions such as calcium and magnesium in the water on the dispersion process. Then, it is diluted to the second dispersion concentration, which can quickly reduce the slurry concentration of the initially disintegrated fiber clumps, reduce the mutual entanglement between fibers, create conditions for subsequent high-strength disintegration, and ensure that the shear force in high-strength disintegration can effectively act on individual fibers, thereby achieving highly uniform dispersion.

[0157] Furthermore, the mixed fiber refers to a slurry composed of target glass fiber raw material and target polymer fiber raw material mixed in deionized water, with the fiber concentration of the mixed fiber being a first dispersion concentration. The dispersant refers to a water-soluble polymer, optionally polyethylene oxide (PEO) or polyvinylpyrrolidone (PVP), etc., as the dispersant. Since the target glass fiber raw material and the target polymer fiber raw material lack hydrophilic groups on their surfaces, they are prone to flocculation and agglomeration in water; therefore, the dispersant needs to be added. This dispersant can adsorb onto the fiber surface and prevent fiber re-agglomeration through electrostatic repulsion or steric hindrance, thereby ensuring the formation of a uniform and stable fiber suspension, i.e., preliminary fiber clump disintegration. The pre-disintegration of the added mixed fiber according to a preset first disintegration intensity refers to: using a disintegration machine (such as a Valley pulper) and according to the first disintegration intensity and a preset running time to disperse the mixed fiber; the dispersed mixed fiber is the pre-disintegrated fiber clump. The subsequent high-intensity disintegration steps are the same as the pre-disintegration steps. The pre-disintegrated fiber clump refers to the mixed fiber after pre-disintegration. The diluted and decomposed fiber clumps refer to the initially decomposed fiber clumps after dilution with water, and the fiber concentration in the diluted and decomposed fiber clumps is the second dispersion concentration. The target fiber slurry refers to the diluted and decomposed fiber clumps after high-strength decomposition.

[0158] It should be explained that the first and second de-disintegration intensities refer to the rotational speed of the de-disintegrating machine per unit time, which is set manually. The second de-disintegration intensity is greater than the first de-disintegration intensity. The first de-disintegration intensity can be half of the minimum de-disintegration in the previous preparation process, and the second de-disintegration intensity can be three or four times that of the first de-disintegration intensity. Optionally, the first de-disintegration intensity and the second de-disintegration intensity are 10,000 rpm and 40,000 rpm, respectively. This scheme adopts a distributed de-disintegration strategy, that is, a pre-de-disintegration with a lower intensity is performed first. This pre-de-disintegration can initially break down the fiber clumps in the mixed fibers at a higher concentration (first dispersion concentration), laying the foundation for the subsequent high-intensity de-disintegration. Then, water is added for dilution, thereby reducing the fiber concentration in the diluted de-disintegrated fiber clumps and reducing the interaction and entanglement between fibers in the diluted de-disintegrated fiber clumps, creating a low-interference environment for high-intensity de-disintegration. Finally, the high shear force of high-intensity de-disintegration is used to act on individual fibers, thereby completing fiber dispersion. The diluted de-disintegrated fiber clumps after fiber dispersion are the target fiber slurry. Compared to traditional one-time high-intensity dispersal, the distributed dispersal strategy adopted in this solution has the advantages of lower energy consumption and higher efficiency, and can avoid problems such as uneven dispersal and equipment overload caused by excessively high initial dispersion concentration.

[0159] Understandably, the raw fiber wet web refers to the wet fiber network structure formed by the target fiber slurry on the forming web of the sheeter, with randomly arranged fibers. The compacted fiber wet web refers to the raw fiber wet web after compaction, which can be performed by a press roller. The forced-air drying oven refers to a device that dries wet materials (such as compacted fiber wet web) by forced circulation of hot air. The dried nonwoven fabric substrate refers to the dried compacted fiber wet web. The bonding fiber refers to a thermoplastic fiber with a low melting point that can be melted by heat during hot pressing. After melting, it flows and wets the contact points of the main fibers (i.e., the fibers corresponding to the target glass fiber raw material and the target polymer fiber raw material). After cooling and solidification at the contact points, a strong bonding point is formed, thereby improving the mechanical strength and structural integrity of the nonwoven fabric substrate. For example, copolyester fibers with a melting point between 110°C and 130°C are used as bonding fibers. The hot-pressing setting temperature refers to the temperature during the subsequent hot-pressing process. This temperature is set precisely to be above the melting point of the bonding fibers but below the decomposition temperature of the main fibers (i.e., the minimum of the subsequent glass fiber and polymer fiber decomposition temperatures) to ensure effective melting and bonding of the bonding fibers while preventing degradation of the main fibers. The hot-pressing of the dried nonwoven fabric substrate using the hot-pressing setting temperature, a hot press, and bonding fibers refers to: feeding the dried nonwoven fabric substrate into a hot press and pressing it at the hot-pressing setting temperature, under specific pressure and for a specified time, allowing the bonding fibers mixed in the dried nonwoven fabric substrate to fully melt, flow, and bond with the main fibers, forming a structurally stable composite nonwoven fabric substrate with sufficient strength after cooling.

[0160] Specifically, the setting of the hot pressing and shaping temperature based on the bonding fiber, the target glass fiber raw material, and the target polymer fiber raw material includes:

[0161] The glass fiber decomposition temperature of the target glass fiber raw material and the polymer fiber decomposition temperature of the target polymer fiber raw material were obtained respectively.

[0162] Find the melting point temperature of the bonding fiber;

[0163] The hot pressing temperature range is constructed based on the melting point temperature of the bonding fiber, the decomposition temperature of the glass fiber, and the decomposition temperature of the polymer fiber.

[0164] The hot-pressing temperature range is divided to obtain multiple test hot-pressing temperatures;

[0165] The test hot-pressing temperature is extracted sequentially from multiple test hot-pressing temperatures, and the substrate is prepared based on the extracted test hot-pressing temperature to obtain the test nonwoven fabric substrate;

[0166] The strength of the nonwoven fabric substrate was tested to obtain the substrate strength.

[0167] By summing the strengths of the substrates, multiple substrate strengths are obtained.

[0168] The strength curves of multiple substrates are obtained by curve fitting based on multiple hot-pressing temperatures.

[0169] The hot pressing and shaping temperature is selected based on the substrate strength curve.

[0170] It is clear that the glass fiber decomposition temperature refers to the temperature at which the target glass fiber raw material decomposes. The polymer fiber decomposition temperature refers to the temperature at which the target polymer fiber raw material decomposes. The bonding fiber melting point temperature refers to the melting point temperature of the bonding fiber. The hot-pressing temperature range refers to the temperature range formed by the minimum value among the bonding fiber melting point temperature, the glass fiber decomposition temperature, and the polymer fiber decomposition temperature, where the minimum value of the hot-pressing temperature range is the bonding fiber melting point temperature, and the maximum value is the minimum value among the glass fiber decomposition temperature and the polymer fiber decomposition temperature. The test hot-pressing temperature refers to a discrete temperature within the hot-pressing temperature range, where dividing the hot-pressing temperature range means dividing the hot-pressing temperature range into multiple test hot-pressing temperatures according to a preset temperature interval. The test nonwoven fabric substrate refers to the composite nonwoven fabric substrate obtained by hot-pressing at the test hot-pressing temperature. The substrate strength refers to the maximum tensile force at which the test nonwoven fabric substrate breaks during a tensile test. The substrate strength curve refers to the curve showing the change between the test hot-pressing temperature and the substrate strength, where the horizontal axis and vertical axis of the substrate strength curve represent the test hot-pressing temperature and the substrate strength, respectively. The above selection of hot-pressing setting temperature based on the substrate strength curve refers to: determining the curve point corresponding to the maximum strength of the substrate in the substrate strength curve, and recording the test hot-pressing temperature corresponding to this curve point as the hot-pressing setting temperature.

[0171] S6. Obtain ceramic particles and polymer adhesive, and use the ceramic particles and polymer adhesive to coat the target nonwoven fabric substrate to obtain a modified nonwoven fabric substrate, wherein the modified nonwoven fabric substrate includes a ceramic polymer functional coating.

[0172] Understandably, the ceramic particles refer to inorganic non-metallic micron-sized particles with high melting point, high hardness, and excellent chemical stability. These ceramic particles are used to impart excellent thermal stability and mechanical strength to the target nonwoven fabric substrate, such as alumina and silica. The polymer adhesive refers to a polymer compound solution capable of firmly bonding the ceramic particles to the target nonwoven fabric substrate, such as polyvinylidene fluoride and sodium carboxymethyl cellulose. The modified nonwoven fabric substrate refers to the target nonwoven fabric substrate after coating. The coating of the target nonwoven fabric substrate using ceramic particles and polymer adhesive involves: first, mixing the ceramic particles and polymer adhesive in a certain proportion in a solvent (such as N-methylpyrrolidone NMP or water) to prepare a stable ceramic slurry; then, uniformly applying the ceramic slurry to both sides of the target nonwoven fabric substrate by means of blade coating, dip coating, or spraying; and finally, removing the solvent from the surface of the target nonwoven fabric substrate through a drying process, thereby forming a composite coating firmly attached to the substrate. This composite coating is the ceramic polymer functional coating. The ceramic polymer functional coating refers to a thin layer composed of ceramic particles and polymer binders, which covers the surface of the target nonwoven fabric substrate.

[0173] S7. Heat-set the modified nonwoven fabric substrate to obtain a composite nonwoven membrane. Based on the composite nonwoven membrane, complete the preparation of a surface-modified lithium battery membrane.

[0174] It should be explained that the composite nonwoven membrane refers to the modified nonwoven substrate after heat setting.

[0175] To address the problems described in the background art, this invention first selects a set of candidate glass fiber types based on the battery electrolyte. This step, through chemical stability testing and selection, ensures the compatibility of the candidate glass fiber types with the electrolyte. Next, membrane preparation tests are conducted based on the candidate glass fiber type set and the candidate polymer fiber type set, resulting in multiple membrane test datasets. This step, by systematically constructing a set of reinforcing material components and conducting membrane preparation tests, comprehensively evaluates the impact of different combinations of glass fibers and polymer fibers on battery cycle life. Compared to existing technologies that rely on empirical selection, this method uses a data-driven approach to optimize fiber ratios, improving the accuracy of membrane performance prediction and preparation efficiency. Then, this scheme optimizes multiple membrane test datasets using response surface methodology to obtain membrane preparation data. This step, utilizing response surface methodology to optimize multiple membrane test datasets, can quickly and accurately find the optimal combination of membrane preparation parameters. Compared to traditional trial-and-error methods, this method reduces experimental complexity through mathematical models and enhances the scientific rigor and reliability of separator performance optimization. Furthermore, based on separator preparation data, wet web forming is performed to obtain a composite nonwoven fabric substrate. This substrate is then subjected to plasma treatment to obtain the target nonwoven fabric substrate. This step employs a staged wet web forming and plasma treatment process. The staged loosening strategy, through pre-loosening followed by high-intensity loosening, improves fiber dispersion uniformity and reduces energy consumption. Plasma treatment enhances the surface activity of the substrate. Compared to the fiber damage that may result from a single high-intensity loosening in existing technologies, this method improves preparation efficiency and quality consistency while ensuring substrate strength. Finally, ceramic particles and polymer binders are obtained and used to coat the target nonwoven fabric substrate, resulting in a modified nonwoven fabric substrate. This step, by coating with ceramic particles and polymer binders to form a functional coating, endows the separator with excellent thermal stability and mechanical strength. Therefore, this invention can improve the cycle life and thermal stability of lithium battery separators and reduce the risk of performance degradation.

[0176] like Figure 2 The diagram shown is a functional block diagram of a surface-modified lithium battery separator preparation system provided in an embodiment of the present invention.

[0177] The surface-modified lithium battery separator preparation system 100 of the present invention can be installed in an electronic device. Depending on the functions implemented, the surface-modified lithium battery separator preparation system 100 may include a glass fiber acquisition module 101, a test data construction module 102, a non-woven fabric substrate preparation module 103, and a composite separator shaping module 104. The module described in this invention can also be called a unit, which refers to a series of computer program segments that can be executed by the processor of an electronic device and can perform a fixed function, and which are stored in the memory of the electronic device.

[0178] The glass fiber acquisition module 101 is used to receive the membrane preparation instruction, determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction, wherein the original glass fiber type set includes multiple original glass fiber types, and the original glass fiber type set is selected based on the battery electrolyte to obtain the candidate glass fiber type set;

[0179] The test data construction module 102 is used to set a candidate polymer fiber type set, and to perform diaphragm preparation tests based on the candidate glass fiber type set and the candidate polymer fiber type set to obtain multiple diaphragm test datasets, wherein the diaphragm test datasets include multiple diaphragm test data.

[0180] The nonwoven fabric substrate preparation module 103 is used to perform response surface methodology optimization based on multiple diaphragm test datasets to obtain diaphragm preparation data. The diaphragm preparation data includes: target glass fiber type, target polymer fiber type and target glass fiber content. Based on the diaphragm preparation data, wet web forming is performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate is then subjected to plasma treatment to obtain the target nonwoven fabric substrate.

[0181] The composite diaphragm shaping module 104 is used to obtain ceramic particles and polymer adhesive, and to coat the target nonwoven fabric substrate with the ceramic particles and polymer adhesive to obtain a modified nonwoven fabric substrate. The modified nonwoven fabric substrate includes a ceramic polymer functional coating. The modified nonwoven fabric substrate is then heat-shaped to obtain a composite nonwoven fabric diaphragm.

[0182] In detail, the modules in the surface-modified lithium battery separator fabrication system 100 described in this embodiment of the invention employ the same methods as described above during use. Figure 1 The same technical means are used in the preparation method of lithium battery separator based on surface modification described in the article, and the same technical effect can be produced, so it will not be repeated here.

[0183] like Figure 3 The diagram shown is a schematic representation of an electronic device that implements a method for preparing a lithium battery separator based on surface modification, according to an embodiment of the present invention.

[0184] The electronic device 1 may include a processor 10, a memory 11 and a bus 12, and may also include a computer program stored in the memory 11 and executable on the processor 10, such as a method program for preparing a lithium battery separator based on surface modification.

[0185] The memory 11 includes at least one type of readable storage medium, such as flash memory, portable hard drive, multimedia card, card-type memory (e.g., SD or DX memory), magnetic memory, disk, optical disk, etc. In some embodiments, the memory 11 can be an internal storage unit of the electronic device 1, such as a portable hard drive. In other embodiments, the memory 11 can be an external storage device of the electronic device 1, such as a plug-in portable hard drive, smart media card (SMC), secure digital card (SD), flash card, etc., equipped on the electronic device 1. Furthermore, the memory 11 includes both internal storage units and external storage devices of the electronic device 1. The memory 11 can be used not only to store application software and various types of data installed on the electronic device 1, such as code for a method of preparing a surface-modified lithium battery separator, but also to temporarily store data that has been output or will be output.

[0186] In some embodiments, the processor 10 may be composed of integrated circuits, such as a single packaged integrated circuit or multiple integrated circuits with the same or different functions, including combinations of one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and various control chips. The processor 10 is the control unit of the electronic device, connecting various components of the entire electronic device through various interfaces and lines. It executes programs or modules stored in the memory 11 (e.g., a method for preparing a lithium battery separator based on surface modification), and calls data stored in the memory 11 to perform various functions of the electronic device 1 and process data.

[0187] The bus 12 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus 12 can be divided into an address bus, a data bus, a control bus, etc. The bus 12 is configured to realize the connection and communication between the memory 11 and at least one processor 10, etc.

[0188] Figure 3 Only electronic devices with components are shown; it will be understood by those skilled in the art that... Figure 3The structure shown does not constitute a limitation on the electronic device 1, and may include fewer or more components than shown, or combine certain components, or have different component arrangements.

[0189] For example, although not shown, the electronic device 1 may also include a power supply (such as a battery) to power the various components. Preferably, the power supply can be logically connected to the at least one processor 10 through a power management device, thereby enabling functions such as charging management, discharging management, and power consumption management. The power supply may also include one or more DC or AC power supplies, recharging devices, power fault detection circuits, power converters or inverters, power status indicators, and other arbitrary components. The electronic device 1 may also include various sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be described in detail here.

[0190] Furthermore, the electronic device 1 may also include a network interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a Wi-Fi interface, a Bluetooth interface, etc.), which is typically used to establish communication connections between the electronic device 1 and other electronic devices.

[0191] Optionally, the electronic device 1 may further include a user interface, which may be a display, an input unit (such as a keyboard), and optionally, a standard wired interface or a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen, etc. The display may also be appropriately referred to as a screen or display unit, used to display information processed in the electronic device 1 and to display a visual user interface.

[0192] The lithium battery separator preparation method program based on surface modification stored in the memory 11 of the electronic device 1 is a combination of multiple instructions. When run in the processor 10, it can achieve the following:

[0193] Receive the membrane preparation instruction, and determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction. The original glass fiber type set includes multiple original glass fiber types.

[0194] Based on the battery electrolyte, the original set of glass fiber types is selected to obtain a set of candidate glass fiber types;

[0195] A candidate set of polymer fiber types is set up, and membrane preparation tests are performed based on the candidate set of glass fiber types and the candidate set of polymer fiber types to obtain multiple membrane test datasets. The membrane test datasets include multiple membrane test data.

[0196] Response surface methodology was used to optimize the membrane preparation data based on multiple membrane test datasets. The membrane preparation data included: target glass fiber type, target polymer fiber type, and target glass fiber content.

[0197] Based on the diaphragm preparation data, wet web forming was performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate was then subjected to plasma treatment to obtain the target nonwoven fabric substrate.

[0198] Ceramic particles and polymer adhesives are obtained, and the target nonwoven fabric substrate is coated with ceramic particles and polymer adhesives to obtain a modified nonwoven fabric substrate, wherein the modified nonwoven fabric substrate includes a ceramic polymer functional coating.

[0199] The modified nonwoven fabric substrate is heat-set to obtain a composite nonwoven membrane. Based on the composite nonwoven membrane, a surface-modified lithium battery membrane is prepared.

[0200] Specifically, the processor 10's implementation method for the above instructions can be found in [reference needed]. Figures 1 to 3 The descriptions of the relevant steps in the corresponding embodiments are not repeated here.

[0201] Furthermore, if the modules / units integrated in the electronic device 1 are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. The computer-readable storage medium can be volatile or non-volatile. For example, the computer-readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, or a read-only memory (ROM).

[0202] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor of an electronic device, can perform the following:

[0203] Receive the membrane preparation instruction, and determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction. The original glass fiber type set includes multiple original glass fiber types.

[0204] Based on the battery electrolyte, the original set of glass fiber types is selected to obtain a set of candidate glass fiber types;

[0205] A candidate set of polymer fiber types is set up, and membrane preparation tests are performed based on the candidate set of glass fiber types and the candidate set of polymer fiber types to obtain multiple membrane test datasets. The membrane test datasets include multiple membrane test data.

[0206] Response surface methodology was used to optimize the membrane preparation data based on multiple membrane test datasets. The membrane preparation data included: target glass fiber type, target polymer fiber type, and target glass fiber content.

[0207] Based on the diaphragm preparation data, wet web forming was performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate was then subjected to plasma treatment to obtain the target nonwoven fabric substrate.

[0208] Ceramic particles and polymer adhesives are obtained, and the target nonwoven fabric substrate is coated with ceramic particles and polymer adhesives to obtain a modified nonwoven fabric substrate, wherein the modified nonwoven fabric substrate includes a ceramic polymer functional coating.

[0209] The modified nonwoven fabric substrate is heat-set to obtain a composite nonwoven membrane. Based on the composite nonwoven membrane, a surface-modified lithium battery membrane is prepared.

[0210] In the embodiments provided by this invention, it should be understood that the disclosed devices, systems, and methods can be implemented in other ways. For example, the system embodiments described above are merely illustrative, and actual implementations may have other classification methods.

[0211] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0212] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0213] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0214] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a lithium battery separator based on surface modification, characterized in that, The method includes: Receive the membrane preparation instruction, and determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction. The original glass fiber type set includes multiple original glass fiber types. Based on the battery electrolyte, the original set of glass fiber types is selected to obtain a set of candidate glass fiber types; A candidate set of polymer fiber types is set up, and membrane preparation tests are performed based on the candidate set of glass fiber types and the candidate set of polymer fiber types to obtain multiple membrane test datasets. The membrane test datasets include multiple membrane test data. Response surface methodology was used to optimize the membrane preparation data based on multiple membrane test datasets. The membrane preparation data included: target glass fiber type, target polymer fiber type, and target glass fiber content. Based on the diaphragm preparation data, wet web forming was performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate was then subjected to plasma treatment to obtain the target nonwoven fabric substrate. Ceramic particles and polymer adhesives are obtained, and the target nonwoven fabric substrate is coated with ceramic particles and polymer adhesives to obtain a modified nonwoven fabric substrate, wherein the modified nonwoven fabric substrate includes a ceramic polymer functional coating. The modified nonwoven fabric substrate is heat-set to obtain a composite nonwoven membrane. Based on the composite nonwoven membrane, a surface-modified lithium battery membrane is prepared.

2. The method for preparing a lithium battery separator based on surface modification as described in claim 1, characterized in that, The selection of candidate glass fiber types based on the battery electrolyte from the original glass fiber type set includes: The original glass fiber types are extracted sequentially from the original glass fiber type set, and the original glass fiber samples are obtained based on the extracted original glass fiber types. The original glass fiber samples were subjected to benchmark performance data collection to obtain a benchmark fiber performance set, which includes benchmark fiber strength and benchmark fiber mass. The original glass fiber sample was immersed in battery electrolyte to test its stability, and the immersed glass fiber sample was obtained. The immersion performance of the glass fiber samples was collected to obtain the immersion fiber performance group, which includes: immersion fiber strength and immersion fiber mass. The performance retention rate group was calculated based on the baseline fiber performance group and the soaked fiber performance group. The chemical stability was obtained by summing the performance retention rate groups. By summarizing the chemical stability data, a chemical stability set is obtained. Based on the preset chemical stability ratio and the chemical stability set, a candidate glass fiber type set is determined from the original glass fiber type set.

3. The method for preparing a lithium battery separator based on surface modification as described in claim 2, characterized in that, The process involves testing the membrane preparation based on candidate glass fiber type sets and candidate polymer fiber type sets, resulting in multiple membrane test datasets, including: A set of reinforcing material components is constructed based on a set of candidate glass fiber types and a set of candidate polymer fiber types. The set of reinforcing material components includes multiple reinforcing material components, and each reinforcing material component contains one candidate glass fiber type and one candidate polymer fiber type. For each reinforcing material component in the reinforcing material component set, the following operation is performed: Set a glass fiber content range, test the reinforcing material components based on the glass fiber content range, and obtain the diaphragm test dataset; By summing up the membrane test datasets corresponding to each reinforcing material component, multiple membrane test datasets are obtained.

4. The method for preparing a lithium battery separator based on surface modification as described in claim 3, characterized in that, The test of the reinforcing material composition based on the glass fiber content range yields a membrane test dataset, including: The glass fiber content range is divided to obtain the test glass fiber content set; A set of test nonwoven membranes is prepared based on the set of test glass fiber content and the composition of reinforcing materials. The set of test nonwoven membranes includes multiple test nonwoven membranes, and each test nonwoven membrane corresponds to a test glass fiber content. Composite membrane tests were performed on each nonwoven membrane in the test nonwoven membrane set to obtain the test battery cycle life set, which includes the cycle life of multiple test batteries. The test battery cycle life set is matched with the test glass fiber content set to obtain the separator test dataset. The separator test dataset includes multiple separator test data, and each separator test data contains a test battery cycle life and a test glass fiber content. By summing up the membrane test datasets corresponding to each reinforcing material component, multiple membrane test datasets are obtained.

5. The method for preparing a lithium battery separator based on surface modification as described in claim 4, characterized in that, The method involves performing composite membrane testing on each nonwoven membrane in the test nonwoven membrane set to obtain a test battery cycle life set, including: The following procedure was performed on each test nonwoven membrane in the test nonwoven membrane set: The mechanical properties of the nonwoven membrane were tested using a pre-constructed mechanical testing device to obtain the tensile strength and puncture strength. The mechanical testing device included a tensile testing machine and a puncture testing machine. Based on the test of nonwoven membrane, a porosity test sample was obtained, and the porosity of the porosity test sample was detected to obtain the test porosity. Thermogravimetric analysis was performed on the tested nonwoven membrane to obtain its thermal stability. The tensile strength, puncture strength, porosity, and thermal stability of the diaphragm were combined to obtain the diaphragm test performance group; The cycle life of the test battery was calculated based on the diaphragm test performance group. The cycle life of the test battery corresponding to each test nonwoven separator is summarized to obtain the test battery cycle life set.

6. The method for preparing a lithium battery separator based on surface modification as described in claim 5, characterized in that, The process of performing porosity testing on the porosity test sample to obtain the test porosity includes: Collect the sample mass and density of the porosity test sample; The porosity test sample is immersed in the pre-obtained n-butanol reagent to obtain the wetting test sample; The mass of the wetting test sample is measured, and the test porosity is calculated based on the mass of the wetting sample, the mass of the test sample, and the density of the test sample. The test porosity is expressed as: ； in, Indicates the test porosity. Indicates the quality of the test sample. Indicates the quality of the impregnated sample. Indicates the density of the test sample. This indicates the preset n-butanol density.

7. The method for preparing a lithium battery separator based on surface modification as described in claim 6, characterized in that, The calculation of the test battery cycle life based on the diaphragm test performance group includes: Construct a battery cycle life correlation table, which includes multiple battery cycle life correlation data, and each battery cycle life correlation data includes: battery cycle life and associated separator performance group; Perform the following operations on each battery life-related data in the battery cycle life association table: Calculate the performance similarity based on the membrane test performance group and the associated membrane performance group in the battery life correlation data; Summarize the performance similarity scores to obtain a performance similarity set, and identify the maximum similarity score within the performance similarity set; The battery life correlation data corresponding to the highest similarity is recorded as the most similar correlation data, and the test battery cycle life is extracted from the most similar correlation data.

8. The method for preparing a lithium battery separator based on surface modification as described in claim 7, characterized in that, The process of wet web formation based on diaphragm preparation data to obtain a composite nonwoven fabric substrate includes: The target glass fiber raw material and the target polymer fiber raw material are obtained based on the target glass fiber type, target polymer fiber type and target glass fiber content in the membrane preparation data. Based on the preset first dispersion concentration, the target glass fiber raw material and the target polymer fiber raw material are added to the pre-obtained deionized water to obtain mixed fibers; Obtain a dispersant, add the dispersant to the mixed fibers, and pre-dissolve the mixed fibers after adding the dispersant according to the preset first dissolution intensity to obtain a preliminary dissolved fiber cluster; Based on the preset second dispersion concentration, the initially disintegrated fiber clusters are diluted with water to obtain diluted disintegrated fiber clusters; The diluted and disintegrated fiber clusters are subjected to high-intensity disintegration according to the preset second disintegration intensity to obtain the target fiber slurry. The target fiber slurry is injected into a pre-constructed fiber generator to obtain a raw fiber wet web, and the raw fiber wet web is compacted to obtain a compacted fiber wet web. The compacted fiber wet web is dried using a pre-designed blower drying oven to obtain a dried nonwoven fabric substrate; Obtain the bonding fiber, and set the hot pressing temperature based on the bonding fiber, the target glass fiber raw material, and the target polymer fiber raw material; A composite nonwoven fabric substrate is obtained by hot pressing a dry nonwoven fabric substrate using a hot pressing setting temperature, a pre-constructed hot press, and bonding fibers.

9. The method for preparing a lithium battery separator based on surface modification as described in claim 8, characterized in that, The setting of the hot pressing and shaping temperature based on the bonding fiber, the target glass fiber raw material, and the target polymer fiber raw material includes: The glass fiber decomposition temperature of the target glass fiber raw material and the polymer fiber decomposition temperature of the target polymer fiber raw material were obtained respectively. Find the melting point temperature of the bonding fiber; The hot pressing temperature range is constructed based on the melting point temperature of the bonding fiber, the decomposition temperature of the glass fiber, and the decomposition temperature of the polymer fiber. The hot-pressing temperature range is divided to obtain multiple test hot-pressing temperatures; The test hot-pressing temperature is extracted sequentially from multiple test hot-pressing temperatures, and the substrate is prepared based on the extracted test hot-pressing temperature to obtain the test nonwoven fabric substrate; The strength of the nonwoven fabric substrate was tested to obtain the substrate strength. By summing the strengths of the substrates, multiple substrate strengths are obtained. The strength curves of multiple substrates are obtained by curve fitting based on multiple hot-pressing temperatures. The hot pressing and shaping temperature is selected based on the substrate strength curve.

10. A lithium battery separator preparation system based on surface modification, characterized in that, The system includes: The glass fiber acquisition module is used to receive the membrane preparation instruction, determine the original glass fiber type set and battery electrolyte based on the membrane preparation instruction, wherein the original glass fiber type set includes multiple original glass fiber types, and selects the original glass fiber type set based on the battery electrolyte to obtain the candidate glass fiber type set; The test data construction module is used to set up a candidate polymer fiber type set, and to conduct membrane preparation tests based on the candidate glass fiber type set and the candidate polymer fiber type set to obtain multiple membrane test datasets. The membrane test datasets include multiple membrane test data. The nonwoven fabric substrate preparation module is used to perform response surface methodology optimization based on multiple diaphragm test datasets to obtain diaphragm preparation data. The diaphragm preparation data includes: target glass fiber type, target polymer fiber type, and target glass fiber content. Based on the diaphragm preparation data, wet web forming is performed to obtain a composite nonwoven fabric substrate. The composite nonwoven fabric substrate is then subjected to plasma treatment to obtain the target nonwoven fabric substrate. A composite diaphragm shaping module is used to obtain ceramic particles and polymer adhesives, and to coat the target nonwoven fabric substrate with the ceramic particles and polymer adhesives to obtain a modified nonwoven fabric substrate. The modified nonwoven fabric substrate includes a ceramic polymer functional coating. The modified nonwoven fabric substrate is then heat-shaped to obtain a composite nonwoven fabric diaphragm.

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