A conductive hydrophobic modified material and a preparation method and application thereof

Abstract

The application relates to a conductive hydrophobic modified material and a preparation method and application thereof. The preparation method comprises the following steps: adding a silicate compound into an alkaline system catalytic solution, stirring for 1-5 h, then increasing the temperature to 40-80 DEG C, adding a hydrophobic agent, stirring for 2-5 h, adding an oxide solid electrolyte containing Ti elements after standing, and continuously stirring for 3-18 h; washing the stirred suspension and obtaining a solid product through centrifugal separation; drying the solid product to obtain a powder material; adding the powder material into an organic solvent for ultrasonic dispersion, spraying or coating a liquid obtained through ultrasonic dispersion on the surface of a solid electrolyte to be modified, and drying to form a solid electrolyte material with a conductive hydrophobic coating, namely the conductive hydrophobic modified material. The application constructs a silicon-oxygen network structure with a hydrophobic alkyl group and bonds with Ti ions, prepares a material with excellent hydrophobicity and conductivity, effectively improves the stability of halide / sulfide solid electrolytes, and has a good capacity retention rate.

Description

Technical Field

[0001] This invention relates to the field of new energy materials technology, and in particular to a conductive hydrophobic modified material, its preparation method, and its application. Background Technology

[0002] Lithium-ion batteries have been widely used in various industries due to their high charge-discharge efficiency, long lifespan, and high specific energy. However, with rapid socio-economic development, the requirements for the energy density, safety, and environmental adaptability of lithium-ion batteries are becoming increasingly stringent. Currently, lithium-ion batteries face limitations in energy density growth and potential safety issues with liquid electrolytes; these shortcomings have become bottlenecks restricting their further development.

[0003] In recent years, all-solid-state lithium batteries have attracted much attention due to their potential for high safety, high energy density, and better compatibility with cathode materials, as they use solid electrolytes instead of traditional liquid electrolytes. As a crucial component of all-solid-state lithium batteries, the performance of the solid electrolyte directly determines the battery's electrochemical characteristics and application environment. However, many solid electrolytes (such as sulfide electrolytes and halide electrolytes) are currently very sensitive to environmental conditions and are prone to chemical reactions upon contact with moisture. For example, halide electrolytes undergo hydrolysis when they absorb moisture or come into contact with water, leading to electrolyte structure damage and decreased conductivity, thus severely affecting the battery's specific capacity and lifespan. This not only limits the battery's stability and reliability but also imposes stringent requirements for anhydrous or inert environments for its production, storage, transportation, and assembly, significantly increasing costs.

[0004] In the prior art, the modification methods for halide / sulfide solid electrolytes mainly include:

[0005] 1. Metal Oxide Coating: The electrolyte is coated with an oxide shell formed by doping with metal oxides (such as zinc oxide) and then oxidizing them. Although this method can improve the water resistance of the electrolyte to some extent, the modified electrolyte is still sensitive to environmental humidity and can only be used in a dry environment with humidity <3%, which is far from meeting the requirements of actual application scenarios.

[0006] 2. Organic polymer modification: Introducing organic polymers (such as glycidyl methacrylate or polystyrene) to coat the surface of the electrolyte. While this method can improve the hydrophobicity of the material, it will significantly reduce the ionic conductivity of the electrolyte, thus affecting the overall performance of the battery.

[0007] Therefore, there is an urgent need for an innovative material that combines high hydrophobicity and high conductivity to effectively solve the humidity sensitivity problem of halide / sulfide electrolytes, while meeting the high performance requirements of solid-state batteries in practical applications. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of existing technologies by providing a conductive hydrophobic modified material, its preparation method, and its applications. By constructing a silicon-oxygen network structure with hydrophobic alkyl groups and bonding it with Ti ions, a material with both excellent hydrophobicity and conductivity is prepared, effectively improving the stability and capacity retention of halide / sulfide electrolytes in solid-state batteries.

[0009] To achieve the above objectives, in a first aspect, the present invention provides a method for preparing a conductive hydrophobic modified material, comprising:

[0010] Add silicate compounds to an alkaline catalytic solution and stir for 1-5 hours. Then heat to 40-80°C, add a hydrophobic agent, stir for 2-5 hours, let stand, add a Ti-containing oxide solid electrolyte and continue stirring for 3-18 hours.

[0011] The stirred suspension was washed and then centrifuged to obtain a solid product. The solid product was then dried to obtain a powder material.

[0012] The powder material is added to an organic solvent and ultrasonically dispersed. The ultrasonically dispersed liquid is sprayed or coated onto the surface of the solid electrolyte to be modified. After drying, a solid electrolyte material with a conductive and hydrophobic coating is formed, which is the conductive and hydrophobic modified material.

[0013] In this process, the silicate ester compounds undergo hydrolysis and condensation in the alkaline catalytic solution. The alkoxy groups in the silicate ester compounds are replaced by hydroxyl groups to form Si-OH. A portion of these Si-OH undergoes dehydration and self-polymerization to form a Si-O-Si network structure, while another portion of the Si-OH provides active sites for further reactions. The hydrophobic agent comprises a hydrophobic alkyl group R and an active group. The hydrophobic agent undergoes a condensation reaction with the Si-OH through the active group, causing the hydrophobic alkyl group R to stably attach to the silicon-oxygen network, forming R-Si-O-Si bonds to provide the material's hydrophobic properties. The Ti in the Ti-containing oxide solid electrolyte reacts with the oxygen in the Si-OH to form stable Si-OTi bonds, thereby improving the material's conductivity.

[0014] Preferably, the silicate compound includes one or more of tetraethyl orthosilicate (TEOS), methyl silicate, and propyl silicate.

[0015] The alkaline catalytic solution comprises: a mixture of alcohol solvent, ammonia water, and deionized water;

[0016] The hydrophobic agent includes one or more of the following: polydimethylsiloxane (PDMS), methyltriethoxysilane (MTES), trimethylchlorosilane, tridecafluorooctyltriethoxysilane (POTS), octadecylsilane (OTS), or hexadecyltrimethylsilane (HDTMS).

[0017] The Ti-containing oxide solid electrolyte is a nanoparticle material with a particle size ≤800nm, including one or more of lithium lanthanum zirconium oxide LLTO, lithium lanthanum zirconium oxide LLZO, lithium titanium phosphate LTP, and lithium titanate LTO.

[0018] The solid electrolyte to be modified includes: sulfide solid electrolyte or halide solid electrolyte.

[0019] Preferably, the mass ratio of the silicate ester compound, the hydrophobic agent, and the Ti-containing oxide solid electrolyte is 1-4:1-4:1.

[0020] Preferably, the stirring includes magnetic stirring;

[0021] The centrifugal separation specifically involves using a centrifuge with a speed of 800-3000 rpm and a centrifugation time of 10-60 min.

[0022] The drying of the solid product specifically involves drying it in a vacuum drying oven at a temperature of 80-140°C for 12-24 hours.

[0023] Preferably, the organic solvent includes one or more of n-hexane, cyclohexane, styrene, and tetrahydrofuran;

[0024] The ultrasonic dispersion time is 30-120 min.

[0025] Preferably, the step of spraying or coating the ultrasonically dispersed liquid onto the surface of the solid electrolyte to be modified, and then drying it to form a solid electrolyte material with a conductive and hydrophobic coating specifically includes:

[0026] The ultrasonically dispersed liquid is loaded into a spray gun and sprayed onto the surface of the solid electrolyte to be modified. It is then placed in a vacuum drying oven to dry, forming a solid electrolyte material with a conductive and hydrophobic coating; or...

[0027] The ultrasonically dispersed liquid is coated onto the surface of the solid electrolyte to be modified, and then dried in a vacuum drying oven to form a solid electrolyte material with a conductive hydrophobic coating; or;

[0028] The ultrasonically dispersed liquid is sprayed onto the surface of the solid electrolyte to be modified using a spray drying method to form a solid electrolyte material with a conductive and hydrophobic coating.

[0029] Secondly, embodiments of the present invention provide a conductive hydrophobic modified material prepared by the method described in the first aspect above.

[0030] Thirdly, embodiments of the present invention provide a solid electrolyte membrane comprising the conductive and hydrophobic modified material described in the second aspect above.

[0031] Fourthly, embodiments of the present invention provide an interface modification material disposed between an electrode and an electrolyte, the interface modification material including the conductive hydrophobic modified material described in the second aspect above.

[0032] Fifthly, embodiments of the present invention provide a solid-state battery comprising the conductive hydrophobic modified material described in the second aspect above.

[0033] The method for preparing conductive hydrophobic modified materials provided in this invention involves the partial dehydration and polymerization of Si-OH groups formed by the hydrolysis and condensation of silicate compounds in an alkaline system to generate a Si-O-Si network. Simultaneously, some Si-OH groups are retained as active sites, which condense with active groups in a hydrophobic agent to stably introduce hydrophobic alkyl groups (R), constructing a silicon-oxygen network structure with significant hydrophobic properties. Furthermore, the Si-OH groups in the silicon-oxygen network can react with Ti-containing oxide solid electrolytes to form Si-O-Ti bonds, allowing the oxide solid electrolyte to be uniformly integrated into the material structure. This novel material possesses both excellent hydrophobic and conductive properties, effectively improving the stability and moisture resistance of halide / sulfide electrolytes in solid-state batteries, and significantly enhancing their capacity retention and electrochemical performance. This method is simple, highly controllable, and provides a new technical path for the development of high-performance solid electrolyte materials. Attached Figure Description

[0034] Figure 1 A flowchart illustrating the preparation method of the conductive hydrophobic modified material provided in this embodiment of the invention. Detailed Implementation

[0035] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0036] This invention provides a method for preparing a conductive hydrophobic modified material, which is used to prepare a solid electrolyte with both excellent hydrophobic and conductive properties, especially a halide or sulfide electrolyte.

[0037] Figure 1 This is a flowchart of the preparation method of the conductive hydrophobic modified material provided in the embodiments of the present invention. The following is in conjunction with... Figure 1 The technical solution of the present invention will be described below.

[0038] The preparation method of the present invention includes:

[0039] Step 110: Add silicate ester compounds to the alkaline catalytic solution and stir for 1-5 hours. Then raise the temperature to 40-80°C, add a hydrophobic agent, stir for 2-5 hours, let stand, add a Ti-containing oxide solid electrolyte and continue stirring for 3-18 hours.

[0040] Specifically, silicate compounds include one or more of tetraethyl orthosilicate (TEOS), methyl silicate, and propyl silicate.

[0041] The alkaline catalytic solution includes a mixture of alcohol solvents, ammonia, and deionized water; wherein, the alcohol solvents may include methanol, ethanol, isopropanol, diethanol, etc.

[0042] Hydrophobic agents include one or more of the following: polydimethylsiloxane (PDMS), methyltriethoxysilane (MTES), trimethylchlorosilane, tridecafluorooctyltriethoxysilane (POTS), octadecylsilane (OTS), or hexadecyltrimethylsilane (HDTMS).

[0043] The Ti-containing oxide solid electrolyte is a nanoparticle material with a particle size ≤800nm, including one or more of lithium lanthanum zirconium oxide (LLTO), lithium lanthanum zirconium oxide (LLZO), lithium titanium phosphate (LTP), and lithium titanate (LTO).

[0044] The mass ratio of the added silicate ester compound, hydrophobic agent, and Ti-containing oxide solid electrolyte is 1-4:1-4:1. The purity of the silicate ester compound, hydrophobic agent, and Ti-containing oxide solid electrolyte is ≥99%.

[0045] In this step, the silicate compounds first undergo hydrolysis in an alkaline catalytic solution. The alkoxy groups in the silicate compounds are replaced by hydroxyl groups to form Si-OH bonds. Subsequently, some of these undergo dehydration and self-polymerization, i.e., condensation, to form a Si-O-Si network structure, while the remaining Si-OH bonds provide active sites for further reactions. The degree of polymerization is controlled by the reaction temperature and time.

[0046] In the Si-O-Si network structure, the number of repeating units of the Si-O backbone in a polymer monomer is preferably 5-10. That is, silicon atoms in a polymer monomer are connected by Si-O-Si to form a network structure, and each polymer monomer (based on silicon) consists of 5 to 10 silicon atoms. The resulting network structure may be linear chain-like, branched, or a three-dimensional network structure.

[0047] The general formula for hydrophobic agents can be expressed as R x Si(OR') 4-xIn this expression, R is a hydrophobic alkyl group, and R' is a reactive active group. Methyltriethoxysilane (MTES), trimethylchlorosilane, tridecafluorooctyltriethoxysilane (POTS), octadecylsilane (OTS), or hexadecyltrimethylsilane (HDTMS) all conform to the above expression. Polydimethylsiloxane (PDMS) is a special case; the basic structure of PDMS consists of repeating dimethylsiloxane units (-Si(CH3)2O-), where each silicon atom is connected to two methyl groups (-CH3) and one oxygen atom. In other words, each silicon atom in PDMS is connected by two methyl groups and one oxygen atom, forming an alternating silicon-oxygen framework structure. The active group in the hydrophobic agent undergoes a condensation reaction with Si-OH, causing the hydrophobic alkyl group R to be stably attached to the silicon-oxygen network, forming R-Si-O-Si bonds, thereby providing the material with hydrophobic properties.

[0048] In other words, the hydrophobic alkyl groups in the hydrophobic agent do not directly participate in the chemical reaction. Instead, they undergo a condensation reaction with Si-OH through active groups, causing the hydrophobic groups to attach to the silicon-oxygen network. These groups reduce the surface energy, preventing water molecules from interacting further with the coating surface and giving the material excellent hydrophobic properties.

[0049] More preferably, the hydrophobic alkyl group in the hydrophobic agent is a long-chain alkyl group or a long-chain fluorinated alkyl group. More preferably, the hydrophobic agent includes one of tridecafluorooctyltriethoxysilane (POTS), octadecylsilane (OTS), or hexadecyltrimethylsilane (HDTMS).

[0050] In oxide solid electrolytes containing Ti, Ti can form stable Si-OTi bonds with oxygen in Si-OH, thereby improving the conductivity of the material.

[0051] Ti ions have a strong affinity for oxygen and readily form covalent or coordinate bonds with oxygen in Si-O, generating stable Si-O-Ti bonds. The bonding of Ti-O may involve both covalent and coordinate bonds simultaneously. When the oxidation state of Ti is low (e.g., TiO2), the bonding may be further strengthened. 4+ In this case, the unpaired electrons of O and the empty orbitals of Ti may form covalent bonds through sharing. When Ti has a strong affinity for oxygen (e.g., Ti...),... 3+ If the electrons in the Si-O-Ti bond are not fully covalent, they may accept lone pairs of electrons from O, forming weaker coordinate bonds. Therefore, in practice, the Si-O-Ti bond may exhibit a mixture of covalent and coordinate characteristics. This bonding enhances electron cloud overlap in the oxide network, reducing the lithium-ion migration barrier and thus improving conductivity. Furthermore, the formation of the Si-O-Ti bond strengthens the network's mechanical properties, preventing structural breakage during cycling. The stable framework helps maintain long-term ion migration channels, ensuring stable high conductivity.

[0052] In this mixing step, the temperature for adding the hydrophobic agent and the Ti-containing oxide solid electrolyte is set at 40-80℃. This means that both the temperature for adding the hydrophobic agent and the temperature for adding the Ti-containing oxide solid electrolyte are 40-80℃, but the two temperatures can be the same or different. For example, the temperature for adding the hydrophobic agent is 50℃, and the temperature for adding the Ti-containing oxide solid electrolyte is 60℃. That is, the temperature for adding the hydrophobic agent is lower than the temperature for adding the Ti-containing oxide solid electrolyte, or the temperature for adding the hydrophobic agent is higher than the temperature for adding the Ti-containing oxide solid electrolyte. Using this temperature range is to appropriately improve the mixing environment to provide sufficient energy to promote the chemical reaction.

[0053] Step 120: Wash the stirred suspension and separate it by centrifugation to obtain a solid product. Dry the solid product to obtain a powder material.

[0054] Specifically, magnetic stirring is the preferred method for mixing.

[0055] Centrifugal separation specifically involves using a centrifuge with a speed of 800-3000 rpm and a centrifugation time of 10-60 minutes.

[0056] Drying is carried out in a vacuum drying oven at a temperature of 80-140℃ for 12-24 hours.

[0057] Step 130: Add the powder material to an organic solvent for ultrasonic dispersion, spray or coat the ultrasonically dispersed liquid onto the surface of the solid electrolyte to be modified, and dry to form a solid electrolyte material with a conductive hydrophobic coating, which is the conductive hydrophobic modified material.

[0058] Specifically, organic solvents include one or more of n-hexane, cyclohexane, styrene, and tetrahydrofuran.

[0059] The ultrasonic dispersion time is 30-120 min.

[0060] The solid electrolyte to be modified preferably includes sulfide solid electrolytes or halide solid electrolytes. Halide electrolytes may include one of LiZrCl5, Li2ZrCl6, LiYCl6, LiPSCCl5, LiSnCl6, and LiInCl5; sulfide solid electrolytes may include Li3PS4, Li7P3S... 11 Li 10 GeP2S 12 Li4SiS4, Li 10 GeP2S 12 (LGPS), Li4SnS4, etc.

[0061] The specific methods for spraying or coating and drying include: spraying with a spray gun followed by drying, direct coating followed by drying, and spray drying.

[0062] Drying after spraying can be done as follows: the ultrasonically dispersed liquid is loaded into the spray gun, sprayed onto the surface of the solid electrolyte to be modified, and then placed in a vacuum drying oven to dry, forming a solid electrolyte material with a conductive and hydrophobic coating; the spray gun uses one of argon, nitrogen or a nitrogen-argon mixture, the spray gun pressure is 20-80 ps i, and the distance between the spray gun and the surface of the solid electrolyte to be modified is 2-10 cm.

[0063] Direct coating followed by drying can be achieved by coating the ultrasonically dispersed liquid onto the surface of the solid electrolyte to be modified, and then drying it in a vacuum drying oven to form a solid electrolyte material with a conductive and hydrophobic coating.

[0064] Spray drying can be achieved by spraying ultrasonically dispersed liquid onto the surface of a solid electrolyte to be modified, forming a solid electrolyte material with a conductive and hydrophobic coating.

[0065] The methods described above are already commonly used techniques in this field. Those skilled in the art can set specific process parameters according to actual needs, which will not be elaborated here.

[0066] The conductive hydrophobic modified material prepared by this invention can be used in solid electrolyte membranes or as an interface modification material between electrodes and electrolytes, and can be applied in solid batteries, especially solid batteries containing sulfide electrolytes or halide electrolytes.

[0067] The method for preparing conductive hydrophobic modified materials provided in this invention involves the partial dehydration and polymerization of Si-OH groups formed by the hydrolysis and condensation of silicate compounds in an alkaline system to generate a Si-OSi network. Simultaneously, some Si-OH groups are retained as active sites, which condense with active groups in a hydrophobic agent to stably introduce hydrophobic alkyl groups (R), constructing a silicon-oxygen network structure with significant hydrophobic properties. Furthermore, the Si-OH groups in the silicon-oxygen network can react with Ti-containing oxide solid electrolytes to form Si-OTi bonds, allowing the oxide solid electrolyte to be uniformly integrated into the material structure. This novel material possesses both excellent hydrophobic and conductive properties, effectively improving the stability and moisture resistance of halide / sulfide electrolytes in solid-state batteries, and significantly enhancing their capacity retention and electrochemical performance. This method is simple, highly controllable, and provides a new technical path for the development of high-performance solid electrolyte materials.

[0068] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0069] Example 1

[0070] Weigh out 10g of tetraethyl orthosilicate (TEOS), 10g of octadecylsilane (OTS), and 10g of LLTO nanoparticles in a mass ratio of 1:1:1.

[0071] Tetraethyl orthosilicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol, and deionized water, and stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, and octadecylsilane (OTS) was added, while stirring for 3 h while maintaining a magnetic stirring speed of 500 rpm. LLTO nanoparticles were then added, and stirring was maintained at a magnetic stirring speed of 500 rpm for 3 h.

[0072] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0073] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0074] Example 2

[0075] Weigh out 18.4g of propyl silicate, 9.2g of polydimethylsiloxane (PDMS), and 9.2g of LATP nanoparticles according to a mass ratio of 2:1:1.

[0076] Propylene silicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol and deionized water, and stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, polydimethylsiloxane (PDMS) was added, and the mixture was stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, and the mixture was stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm.

[0077] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0078] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0079] Example 3

[0080] Weigh out 6.5g of tetraethyl orthosilicate (TEOS), 13g of hexadecyltrimethylsilane (HDTMS), and 6.5g of LATP nanoparticles in a mass ratio of 1:2:1.

[0081] Tetraethyl orthosilicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol, and deionized water, and stirred for 3 h at a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, and hexadecyltrimethylsilane (HDTMS) was added, and stirred for 3 h at a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, and stirred for 3 h at a magnetic stirring speed of 500 rpm.

[0082] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0083] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0084] Example 4

[0085] Weigh out 6.5g of methyl silicate, 13g of hexadecyltrimethylsilane (HDTMS), and 6.5g of LATP nanoparticles in a mass ratio of 1:2:1.

[0086] Methyl silicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol, and deionized water, and stirred for 3 h at a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, and hexadecyltrimethylsilane (HDTMS) was added, and stirred for 3 h at a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, and stirred for 3 h at a magnetic stirring speed of 500 rpm.

[0087] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0088] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0089] Example 5

[0090] Weigh out 6.5g of methyl silicate, 13g of trimethylchlorosilane, and 6.5g of LATP nanoparticles according to a mass ratio of 1:2:1.

[0091] Methyl silicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol and deionized water, and stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, and trimethylchlorosilane was added, while stirring for 3 h while maintaining a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, while stirring for 3 h while maintaining a magnetic stirring speed of 500 rpm.

[0092] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0093] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0094] Example 6

[0095] Weigh out 6.5g of tetraethyl orthosilicate (TEOS), 13g of methyltriethoxysilane, and 6.5g of LATP nanoparticles in a mass ratio of 1:2:1.

[0096] Tetraethyl orthosilicate (TEOS) was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol, and deionized water, and stirred for 3 h at a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, methyltriethoxysilane was added, and the mixture was stirred for 3 h at a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, and the mixture was stirred for 3 h at a magnetic stirring speed of 500 rpm.

[0097] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0098] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0099] Example 7

[0100] Weigh out 6.5g of propyl silicate, 13g of octadecylsilane (OTS), and 6.5g of LATP nanoparticles in a mass ratio of 1:2:1.

[0101] Propyl silicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol and deionized water, and stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, and octadecylsilane (OTS) was added, while stirring for 3 h while maintaining a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, and stirring was maintained for 3 h while maintaining a magnetic stirring speed of 500 rpm.

[0102] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0103] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0104] Example 8

[0105] Weigh out 6.5g of propyl silicate, 13g of hexadecyltrimethylsilane (HDTMS), and 6.5g of LATP nanoparticles in a mass ratio of 1:2:1.

[0106] Propyl silicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol, and deionized water, and stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, and hexadecyltrimethylsilane (HDTMS) was added, while stirring for 3 h while maintaining a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, and stirring was maintained for 3 h while maintaining a magnetic stirring speed of 500 rpm.

[0107] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0108] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain a conductive hydrophobic modified halide electrolyte material with an oxide hydrophobic coating.

[0109] Comparative Example 1

[0110] Weigh out 13g of tetraethyl orthosilicate (TEOS) and 13g of hexadecyltrimethylsilane (HDTMS) in a mass ratio of 1:1.

[0111] Tetraethyl orthosilicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol and deionized water, and stirred for 3 h while maintaining a magnetic stirrer speed of 500 rpm. The temperature was then raised to 50 °C, and hexadecyltrimethylsilane (HDTMS) was added, while stirring for 3 h while maintaining a magnetic stirrer speed of 500 rpm.

[0112] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0113] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain the modified halide electrolyte material.

[0114] Comparative Example 2

[0115] Weigh out 10g of tetraethyl orthosilicate (TEOS) and 10g of LATP nanoparticles at a mass ratio of 1:1.

[0116] Tetraethyl orthosilicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol and deionized water, and stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. The temperature was then raised to 50 °C, LATP nanoparticles were added, and the mixture was stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm.

[0117] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0118] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain the modified halide electrolyte material.

[0119] Comparative Example 3

[0120] Weigh out 10g of hexadecyltrimethylsilane (HDTMS) and 10g of LATP nanoparticles at a mass ratio of 1:1.

[0121] A 300 mL solution was prepared by mixing ammonia, anhydrous ethanol, and deionized water in equal proportions. The solution was heated to 50 °C, and hexadecyltrimethylsilane was added. The mixture was stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm. LATP nanoparticles were then added, and the mixture was stirred for 3 h while maintaining a magnetic stirring speed of 500 rpm.

[0122] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0123] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain the modified halide electrolyte material.

[0124] Comparative Example 4

[0125] Weigh out 10g of tetraethyl orthosilicate (TEOS), 10g of octadecylsilane (OTS), and 10g of LLTO nanoparticles in a mass ratio of 1:1:1.

[0126] Tetraethyl orthosilicate was slowly added to a 300 mL solution of equal parts ammonia, anhydrous ethanol, and deionized water, and stirred for 0.5 h while maintaining a magnetic stirrer speed of 500 rpm. The temperature was then raised to 50 °C, octadecylsilane was added, and the mixture was stirred for 3 h while maintaining a magnetic stirrer speed of 500 rpm. Finally, LLTO nanoparticles were added, and the mixture was stirred for 3 h while maintaining a magnetic stirrer speed of 500 rpm.

[0127] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0128] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain the modified halide electrolyte material.

[0129] Comparative Example 5

[0130] Weigh out 10g of tetraethyl orthosilicate (TEOS), 10g of perfluorodecyltriethoxysilane (PFDTES), and 10g of LLTO nanoparticles in a mass ratio of 1:1:1.

[0131] Tetraethyl orthosilicate (TEOS), perfluorodecyltriethoxysilane (PFDTES), and LLTO nanoparticles were slowly added together to a 300 mL solution of equal parts ammonia, anhydrous ethanol, and deionized water. The magnetic stirring speed was maintained at 500 rpm for 3 h.

[0132] The stirred solution was placed in a centrifuge, the centrifuge speed was set to 1000 rpm and the centrifugation time was 20 min. The solid product obtained by centrifugation was washed three times with ethanol. The washed product was placed in a vacuum drying oven, the drying temperature was set to 60℃ and the drying time was 12 h.

[0133] The dried powder material was taken out and ultrasonically dispersed in hexane solvent for 30 minutes. The dispersed liquid was then loaded into a spray gun and sprayed onto LiZrCl5 under argon pressure of 20 ps i. The material was then placed in a vacuum drying oven at 80°C for 30 minutes to obtain the modified halide electrolyte material.

[0134] The above embodiments and comparative examples are designed to illustrate the role of each key technical feature in the technical solution of the present invention. Although the above embodiments do not cover all endpoint values ​​of the parameters of the present invention or all possible material selections for realizing the present invention, this does not mean that the materials, processes, parameters, etc., that can realize the technical solution of the present invention are limited by the above embodiments. Those skilled in the art will understand from the description of the range of material selections and process conditions in the invention content and specific embodiments that materials, processes, and parameters within the above-described range can all realize the technical solution of the present invention. It is also understood that the technical solution of the present invention can also be applied to the modification of sulfide electrolyte materials.

[0135] The above embodiments and comparative examples were tested.

[0136] 1. Contact Angle (SCA) Test

[0137] The contact angle is the angle between the liquid-solid contact point and the tangent of the liquid surface tension when the droplet is in static equilibrium on a solid surface. It is used to characterize the wetting behavior of a liquid on a material surface.

[0138] The contact angle (SCA) of water droplets on the samples was measured using an automatic contact angle meter. Three different points were tested on each sample to obtain the average SCA. The results are recorded in Table 1.

[0139] 2. Electrochemical testing

[0140] Mixed cathode LiNi 0.8 Mn 0.1 Co 0.1 2 mg of O2 powder and 2.5 mg of mixed Li-In alloy anode powder were evenly coated on both sides of the electrolyte materials prepared in each example and comparative example, and pressed under a pressure of 600 MPa. Afterwards, the materials, along with the mold, were placed in a biochemical incubator and subjected to electrochemical charge-discharge cycles at 70% RH.

[0141] The battery is charged in constant current and constant voltage mode. After charging to the upper limit voltage of 4V at a current of 0.5C, the constant voltage is maintained and charging continues until the current drops to 0.05C. Then, it is discharged at a constant current of 0.5C until the termination voltage of 0.01V is reached. After resting for 30 minutes, the next cycle begins. One cycle consists of one charge and one discharge. The capacity retention rate is calculated every 50 cycles, and the capacity retention rate is finally tested after 200 cycles.

[0142] SCA / ° Capacity retention rate / 200 cycles Example 1 160.7±0.3 83％ Example 2 164.6±0.2 85％ Example 3 165.9±0.1 89％ Example 4 166.3±0.5 86％ Example 5 167.3±0.6 84％ Example 6 166.4±0.4 81％ Example 7 165.9±0.2 83％ Example 8 165.8±0.1 80％ Comparative Example 1 161.8±0.4 4％ Comparative Example 2 116.3±0.3 11％ Comparative Example 3 118.0±0.5 30％ Comparative Example 4 155.8±0.2 61％ Comparative Example 5 148.4±0.1 58％

[0143] Table 1

[0144] The comparison of the SCA tests of the examples with those of Comparative Examples 2 and 3 shows that:

[0145] In Comparative Example 2, no hydrophobic agent was added, and the contact angle was significantly smaller than that of the examples in which hydrophobic agent was added. The hydrophobicity of the material was significantly worse than that of the examples.

[0146] In Comparative Example 3, no silicate compounds were added, resulting in a lack of sufficient chemically active sites (Si-OH groups) on the surface of the LATP particles. This made it difficult for the hydrophobic agent to bind evenly to the surface, thus significantly reducing the hydrophobicity of the coating.

[0147] It is evident that, under the combined action of silicate compounds, catalysts, and hydrophobic agents, the surface of oxide electrolyte materials is successfully coated with hydrophobic materials, resulting in a significant improvement in the contact angle test results and thus a marked improvement in the hydrophobic properties of solid electrolyte materials.

[0148] The electrochemical tests of the examples and comparative examples 1, 4, and 5 show that:

[0149] In Comparative Example 1, no oxide electrolyte particles were added, resulting in very low capacity retention. In the examples, the addition of oxide electrolytes not only isolated moisture but also maintained normal lithium-ion transport, enabling the halide electrolyte to maintain good capacity retention in high-moisture environments.

[0150] In Comparative Example 4, the short self-polymerization time of the silicate ester resulted in the inability to form a stable and effective self-polymer structure, hindering the formation of uniform crosslinks with the siloxane and thus affecting the capacity retention rate. This is because the sufficiency of the initial hydrolysis reaction and the formation of siloxane bonds after TEOS is added to the solution directly affects the directional adhesion and uniform distribution of OTS. Insufficient stirring time (0.5 hours in Comparative Example 4) causes some TEOS to only partially hydrolyze or remain in an oligomeric state, resulting in an unstable siloxane network and thus affecting the cycling capacity retention rate of the material.

[0151] In Comparative Example 5, the simultaneous addition of silicate ester, siloxane and nanoelectrolyte resulted in the inability to uniformly disperse the electrolyte, which in turn affected the capacity retention rate.

[0152] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a conductive hydrophobic modified material, characterized in that, The preparation method includes: Add silicate compounds to an alkaline catalytic solution and stir for 1-5 hours. Then heat to 40-80℃, add a hydrophobic agent, stir for 2-5 hours, let stand, add a Ti-containing oxide solid electrolyte and continue stirring for 3-18 hours. The stirred suspension was washed and then centrifuged to obtain a solid product. The solid product was then dried to obtain a powder material. The powder material is added to an organic solvent and ultrasonically dispersed. The ultrasonically dispersed liquid is sprayed or coated onto the surface of the solid electrolyte to be modified. After drying, a solid electrolyte material with a conductive and hydrophobic coating is formed, which is the conductive and hydrophobic modified material. In this process, the silicate ester compounds undergo hydrolysis and condensation in the alkaline catalytic solution. The alkoxy groups in the silicate ester compounds are replaced by hydroxyl groups to form Si-OH. A portion of these Si-OH undergoes dehydration and self-polymerization to form a Si-O-Si network structure, while another portion of the Si-OH provides active sites for further reactions. The hydrophobic agent comprises a hydrophobic alkyl group R and an active group. The hydrophobic agent undergoes a condensation reaction with the Si-OH through the active group, causing the hydrophobic alkyl group R to stably attach to the silicon-oxygen network, forming R-Si-O-Si bonds to provide the material's hydrophobic properties. The Ti in the Ti-containing oxide solid electrolyte reacts with the oxygen in the Si-OH to form stable Si-O-Ti bonds, thereby improving the material's conductivity.

2. The preparation method according to claim 1, characterized in that, The silicate compounds include one or more of tetraethyl orthosilicate (TEOS), methyl silicate, and propyl silicate. The alkaline catalytic solution comprises: a mixture of alcohol solvent, ammonia water, and deionized water; The hydrophobic agent includes one or more of the following: polydimethylsiloxane (PDMS), methyltriethoxysilane (MTES), trimethylchlorosilane, tridecafluorooctyltriethoxysilane (POTS), octadecylsilane (OTS), or hexadecyltrimethylsilane (HDTMS). The Ti-containing oxide solid electrolyte is a nanoparticle material with a particle size ≤800nm, including one or more of lithium lanthanum zirconium oxide LLTO, lithium lanthanum zirconium oxide LLZO, lithium titanium phosphate LTP, and lithium titanate LTO. The solid electrolyte to be modified includes: sulfide solid electrolyte or halide solid electrolyte.

3. The preparation method according to claim 1, characterized in that, The mass ratio of the silicate ester compound, the hydrophobic agent, and the Ti-containing oxide solid electrolyte is 1-4:1-4:

1.

4. The preparation method according to claim 1, characterized in that, The stirring includes magnetic stirring; The centrifugal separation specifically involves using a centrifuge with a speed of 800-3000 rpm and a centrifugation time of 10-60 min. The drying of the solid product specifically involves drying it in a vacuum drying oven at a temperature of 80-140°C for 12-24 hours.

5. The preparation method according to claim 1, characterized in that, The organic solvent includes one or more of n-hexane, cyclohexane, styrene, and tetrahydrofuran; The ultrasonic dispersion time is 30-120 min.

6. The preparation method according to claim 1, characterized in that, The process of spraying or coating the ultrasonically dispersed liquid onto the surface of the solid electrolyte to be modified, and then drying it to form a solid electrolyte material with a conductive and hydrophobic coating, specifically includes: The ultrasonically dispersed liquid is loaded into a spray gun and sprayed onto the surface of the solid electrolyte to be modified. It is then placed in a vacuum drying oven to dry, forming a solid electrolyte material with a conductive and hydrophobic coating; or... The ultrasonically dispersed liquid is coated onto the surface of the solid electrolyte to be modified, and then dried in a vacuum drying oven to form a solid electrolyte material with a conductive hydrophobic coating; or; The ultrasonically dispersed liquid is sprayed onto the surface of the solid electrolyte to be modified using a spray drying method to form a solid electrolyte material with a conductive and hydrophobic coating.

7. A conductive hydrophobic modified material prepared by a method according to any one of claims 1-6.

8. A solid electrolyte membrane, characterized in that, The solid electrolyte membrane comprises the conductive hydrophobic modified material described in claim 7.

9. An interface modification material, characterized in that, The interface modification material is disposed between the electrode and the electrolyte, and the interface modification material includes the conductive hydrophobic modified material as described in claim 7.

10. A solid-state battery, characterized in that, The solid-state battery includes the conductive hydrophobic modified material described in claim 7.

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