Anode material based on hierarchical cooperative dynamic reversible buffer layer and preparation method thereof
By constructing a hierarchical synergistic dynamic reversible buffer layer on the surface of silicon-based materials, the inner layer of metal oxide/hydroxide provides support, the middle layer of flexible alkyl backbone buffers, and the outer layer of Si-OB dynamic covalent network realizes stress dissipation and self-repair, the structural instability problem caused by volume changes in silicon-based materials is solved, and the cycle stability and electrochemical performance of lithium-ion batteries are improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HARBIN INST OF TECH
- Filing Date
- 2026-06-11
- Publication Date
- 2026-07-31
AI Technical Summary
Silicon-based anode materials in lithium-ion batteries suffer from pulverization, material shedding, and electrolyte consumption due to volume changes, leading to battery capacity decay and shortened cycle life. Existing coating strategies are unable to effectively absorb stress and lack self-healing capabilities.
A hierarchical, synergistic, dynamic, and reversible buffer layer is constructed on the surface of a silicon-based material. The inner layer is a metal oxide/hydroxide layer that provides structural support, the middle layer is a flexible alkyl backbone buffer, and the outer layer is a Si-OB dynamic covalent network, thereby achieving stress dissipation and self-healing.
It effectively alleviates the structural instability of silicon-based materials caused by volume changes, and improves the cycle stability and electrochemical performance of lithium-ion batteries.
Smart Images
Figure CN122494631A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery materials technology, specifically to a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer and its preparation method. Background Technology
[0002] As the mainstream energy storage device, the performance improvement of lithium-ion batteries is crucial for the development of industries such as electric vehicles and consumer electronics. Silicon anode materials are considered an ideal choice for high-energy-density batteries due to their theoretical specific capacity of up to 4200 mAh / g. However, silicon undergoes a huge volume change (over 300%) during lithium insertion / extraction, leading to material pulverization, detachment from the current collector, and continuous consumption of electrolyte to form an unstable solid-electrolyte interface (SEI). Ultimately, this results in a sharp decline in battery capacity and a shortened cycle life, severely restricting its commercial application.
[0003] To alleviate these problems, researchers have developed various surface modification strategies, including carbon coating, metal oxide coating, and polymer coating. However, traditional carbon coatings lack mechanical flexibility and cannot withstand the repeated volume expansion of silicon-based materials; rigid metal oxide coatings, while providing some structural support, are prone to cracking or even detachment due to stress concentration during long-term cycling; and polymer coatings often suffer from poor conductivity and insufficient high-temperature stability. Furthermore, the interfacial connections formed by traditional coating strategies are mostly physical adsorption or irreversible covalent bonding. Once the coating is damaged or cracked during cycling, it lacks self-repair capabilities, leading to the re-exposure of the silicon-based material to the electrolyte, triggering continuous side reactions and capacity decay.
[0004] Therefore, constructing a buffer layer that can effectively absorb and release stress, maintain the integrity of the material structure, and has self-healing function is of great significance for improving the cycle stability of silicon-based anodes. Summary of the Invention
[0005] This invention addresses the shortcomings of existing technologies by providing a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer and its preparation method. The invention forms a hierarchical synergistic dynamic reversible buffer layer on the surface of a silicon-based material. The bottom metal oxide / hydroxide interface layer provides a stable coordination anchoring foundation for the upper structure and also provides structural rigidity. The flexible alkyl backbone connecting the active functional groups and silicon atoms in the middle extends outwards, buffering volume stress through conformational changes in flexible C / O single bonds. The outermost Si-OB dynamic covalent crosslinking network dissipates energy and provides self-healing function through reversible fracture and recombination under stress overload. This three-layer hierarchical synergy fundamentally solves the cycling instability problem caused by drastic volume changes in silicon-based materials.
[0006] To address the aforementioned technical problems, the first aspect of this invention provides a method for preparing a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer, comprising the following steps:
[0007] S1. Deposit metal oxides or hydroxides in situ on the surface of silicon-based materials to obtain precursor materials;
[0008] S2. The precursor material is mixed with a silane coupling agent containing functional groups in an organic solvent. The functional groups coordinate with the metal atoms on the surface of the precursor material to form an elastic siloxane end base layer, thereby obtaining an intermediate material. In the elastic siloxane end base layer, the flexible alkyl backbone connecting the functional groups and silicon atoms extends outward to form an elastic siloxane end base layer with an inverted structure. The C-C single bonds in the alkyl backbone are in a free rotation state, providing the material with intrinsic flexibility and elastic response.
[0009] S3. The intermediate material and the boron-containing compound are mixed in a mixed solvent of water and organic solvent to carry out hydrolysis and dehydration condensation reaction; wherein, the alkoxy group of the silane coupling agent is hydrolyzed and reacts with the boron-containing compound to form a Si-OB dynamic crosslinking network layer with Si-OB dynamic covalent bonds as the core at the end of the freely extended alkyl main chain, thereby obtaining the negative electrode material based on the hierarchical synergistic dynamic reversible buffer layer.
[0010] Furthermore, in S1, metal oxides or hydroxides are deposited by atomic layer deposition, chemical bath deposition, hydrothermal deposition, sol-gel deposition, or hydrolysis deposition.
[0011] Furthermore, the oxide or hydroxide of the metal is 0.1-50% of the mass of the silicon-based material.
[0012] Furthermore, in S2, the functional group is selected from one or more of amino, mercapto, epoxy, and urea groups.
[0013] Furthermore, in S2, the silane coupling agent is selected from one or more of 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylenediamine, 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, and ureapropyltriethoxysilane.
[0014] Furthermore, in S2, the organic solvent is selected from one or more of methanol, ethanol, isopropanol, benzene, toluene, p-xylene, m-xylene, acetonitrile, N,N-dimethylformamide, and dimethyl sulfoxide.
[0015] Furthermore, in S2, the silane coupling agent accounts for 0.1-50% of the precursor material mass.
[0016] Furthermore, in S3, the boron-containing compound is selected from one or more of boric acid, borax, phenylboronic acid, 1,3-phenyldiboronic acid, 1,4-phenyldiboronic acid, trimethyl borate, and tributyl borate.
[0017] Furthermore, in S3, the organic solvent is selected from one or more of methanol, ethanol, isopropanol, ethylene glycol, and glycerol.
[0018] Furthermore, in S3, the boron-containing compound accounts for 0.1-10% of the mass of the intermediate material.
[0019] Furthermore, in S1, the silicon-based material is selected from one or more of silicon, silicon suboxide, and silicon-carbon composite materials.
[0020] Furthermore, in S1, the metal is selected from one or more of magnesium, aluminum, titanium, iron, cobalt, nickel, copper, zinc, gallium, germanium, zirconium, silver, indium, tin, and antimony.
[0021] Furthermore, in S2, the reaction temperature is 25-100°C.
[0022] Furthermore, in S3, the temperature of the hydrolysis and dehydration condensation reaction is 25-200℃.
[0023] The second aspect of the present invention provides a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer prepared by the preparation method described in the first aspect.
[0024] A third aspect of the present invention provides a lithium-ion battery comprising the negative electrode material described in the second aspect.
[0025] The beneficial effects of this invention are:
[0026] This invention constructs a hierarchical, synergistic, dynamic, and reversible buffer layer on the surface of a silicon-based material. The inner layer is a metal oxide / hydroxide layer serving as an inner coordination support layer. On the one hand, it provides a strong coordination anchor point for the inverted siloxane end base layer; on the other hand, it has a certain lithium-ion conductivity and structural rigidity, synergistically suppressing volume expansion. The middle layer is a flexible alkyl backbone layer formed by the outward extension of the flexible alkyl backbone of the silane coupling agent. Through conformational changes of the C-C single bonds, it achieves first-level stress absorption at the molecular scale, providing rapid and reversible elastic buffering for the volume expansion / contraction of the silicon-based material. The outer layer is a Si-OB dynamic covalent bond network formed by the siloxane end groups of the silane coupling agent and boron-containing compounds. When the stress exceeds the buffer threshold of the alkyl backbone, it achieves second-level stress dissipation through reversible fracture. After stress removal, it self-repairs and reconstructs. The synergistic effect of the two mechanisms fundamentally alleviates the stress concentration problem while avoiding permanent damage to the buffer layer.
[0027] This invention can precisely control the composition, crosslinking density, and thickness of the buffer layer by adjusting parameters such as the type and thickness of the metal oxide / hydroxide, the type and amount of the silane coupling agent, the type and concentration of the boride, and the reaction temperature and time, thereby adapting to the modification requirements of different silicon-based anode materials.
[0028] The negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer prepared by this invention has made significant progress in improving the electrochemical performance of lithium-ion batteries, while also exhibiting excellent stability. Attached Figure Description
[0029] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0030] Figure 1 This is a schematic diagram of the negative electrode material based on the hierarchical synergistic dynamic reversible buffer layer of the present invention;
[0031] Figure 2 The Fourier transform infrared spectrum of the negative electrode material based on the hierarchical synergistic dynamic reversible buffer layer obtained in Embodiment 1 of the present invention;
[0032] Figure 3 The SEM image and corresponding EDS image of the precursor obtained in step (1) of Example 2 are shown.
[0033] Figure 4 This is a graph showing the first charge-discharge curves of the battery assembled with the negative electrode material in Example 1;
[0034] Figure 5The graph shows the cycling performance of the battery assembled with the negative electrode material in Example 1 at a current density of 0.5 A / g.
[0035] Figure 6 The graph shows the cycling performance of the battery assembled with the negative electrode material in Example 2 at a current density of 0.5 A / g.
[0036] Figure 7 The graph shows the cycling performance of the battery assembled with the negative electrode material of Comparative Example 1 at a current density of 0.5 A / g.
[0037] Figure 8 The graph shows the cycling performance of the battery assembled with the negative electrode material of Comparative Example 2 at a current density of 0.5 A / g. Detailed Implementation
[0038] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0039] This embodiment relates to a method for preparing a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer, including the following steps:
[0040] S1. Deposit metal oxides or hydroxides in situ on the surface of silicon-based materials to obtain precursor materials;
[0041] S2. The precursor material is mixed with a silane coupling agent containing functional groups in an organic solvent. The functional groups coordinate with the metal atoms on the surface of the precursor material to form an elastic siloxane end base layer, thereby obtaining an intermediate material. In the elastic siloxane end base layer, the flexible alkyl backbone connecting the functional groups and silicon atoms extends outward to form an elastic siloxane end base layer with an inverted structure. The C-C single bonds in the alkyl backbone are in a free rotation state, providing the material with intrinsic flexibility and elastic response.
[0042] S3. The intermediate material and the boron-containing compound are mixed in a mixed solvent of water and organic solvent to undergo hydrolysis and dehydration condensation reactions; wherein, the alkoxy groups of the silane coupling agent are hydrolyzed and react with the boron-containing compound to form a Si-OB dynamic crosslinking network layer with Si-OB dynamic covalent bonds as the core at the ends of the freely extending alkyl backbone, thus obtaining the negative electrode material based on the hierarchical synergistic dynamic reversible buffer layer, such as... Figure 1 As shown, it includes a core silicon-based material, an inner metal oxide / hydroxide layer, an intermediate alkyl backbone, and an outer Si-OB dynamic cross-linked network layer.
[0043] In a preferred embodiment, in S1, the oxide or hydroxide of the metal is deposited by atomic layer deposition, chemical bath deposition, hydrothermal deposition, sol-gel deposition, or hydrolytic deposition; the oxide or hydroxide of the metal is 0.1-50% of the mass of the silicon-based material; the silicon-based material is selected from one or more of silicon, silicon suboxide, and silicon-carbon composite materials; the metal is selected from one or more of magnesium, aluminum, titanium, iron, cobalt, nickel, copper, zinc, gallium, germanium, zirconium, silver, indium, tin, and antimony.
[0044] In a preferred embodiment, in S2, the functional group is selected from one or more of amino, mercapto, epoxy, and urea groups; preferably, the silane coupling agent is selected from one or more of 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylenediamine, 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, and ureapropyltriethoxysilane; the organic solvent is selected from one or more of methanol, ethanol, isopropanol, benzene, toluene, p-xylene, m-xylene, acetonitrile, N,N-dimethylformamide, and dimethyl sulfoxide; the silane coupling agent accounts for 0.1-50% of the precursor material mass.
[0045] In a preferred embodiment, in S3, the boron-containing compound is selected from one or more of boric acid, borax, phenylboronic acid, 1,3-phenyldiboronic acid, 1,4-phenyldiboronic acid, trimethyl borate, and tributyl borate; the organic solvent is selected from one or more of methanol, ethanol, isopropanol, ethylene glycol, and glycerol; and the boron-containing compound is 0.1-10% of the mass of the intermediate material.
[0046] In a preferred embodiment, in S2, the reaction temperature is 25-100℃; in S3, the temperature of the hydrolysis and dehydration condensation reaction is 25-200℃.
[0047] Another embodiment provides a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer prepared by the preparation method described in the above embodiments.
[0048] Another embodiment provides a lithium-ion battery comprising the negative electrode material described in the above embodiments.
[0049] Example 1
[0050] This embodiment relates to a method for preparing a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer, including the following steps:
[0051] (2) 2 g of silica was dispersed in a mixture containing 200 mL of anhydrous ethanol and 1 mL of ammonia (28 wt%), and 5 mL of tetrabutyl titanate was slowly added dropwise. After stirring evenly, the mixture was transferred to a round-bottom flask and reacted at room temperature for 24 hours. After the reaction was completed, the mixture was centrifuged, washed several times with deionized water and ethanol, and dried under vacuum at 80 °C to obtain a silica precursor with titanium dioxide deposited on its surface. The titanium dioxide loading was approximately 5 wt%.
[0052] (2) The precursor obtained in step (1) was ultrasonically dispersed in 100 mL of anhydrous p-xylene, and 0.5 mL of 3-aminopropyltriethoxysilane was added. The mixture was reacted at 80 °C for 10 h. After the reaction was completed, the mixture was centrifuged and washed three times with anhydrous p-xylene to obtain the intermediate material with the inverted silane layer.
[0053] (3) The intermediate material obtained in step (2) was dispersed in a mixture of 80 mL isopropanol and 2 mL deionized water, and 0.2 g of 1,4-phenylenediboric acid was added. The mixture was reacted at 80 °C for 12 h. After the reaction was completed, the mixture was centrifuged, washed with ethanol, and dried under vacuum at 80 °C to obtain the anode material based on the hierarchical synergistic dynamic reversible buffer layer.
[0054] Example 2
[0055] This embodiment relates to a method for preparing a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer, including the following steps:
[0056] (1) 2g of silicon suboxide was dispersed in 200mL of deionized water, 0.7g of tin tetrachloride pentahydrate and 0.1g of sodium hydroxide were added, stirred evenly and then transferred to a round-bottom flask and reacted at 80℃ for 6h. After the reaction was completed, the mixture was centrifuged, washed several times with deionized water and ethanol, and dried under vacuum at 80℃ to obtain a silicon suboxide precursor with tin hydroxide deposited on its surface, with a tin hydroxide loading of about 12wt%.
[0057] (2) The precursor obtained in step (1) was ultrasonically dispersed in 100 mL of anhydrous toluene, and 0.5 mL of 3-mercaptopropyltrimethoxysilane was added. The mixture was reacted at 60 °C for 4 h under nitrogen protection. After the reaction was completed, the mixture was centrifuged and washed three times with anhydrous toluene to obtain the inverted silane layer intermediate material.
[0058] (3) The intermediate material obtained in step (2) was dispersed in a mixture of 45 mL ethanol and 5 mL deionized water, and 0.1 g boric acid was added. The mixture was reacted at 60 °C for 12 h under nitrogen protection. After the reaction was completed, the mixture was centrifuged, washed with ethanol, and dried under vacuum at 80 °C to obtain the anode material based on the hierarchical synergistic dynamic reversible buffer layer.
[0059] Comparative Example 1
[0060] The difference between this comparative example and Example 2 is that steps (2)-(3) are omitted to obtain a silicon suboxide anode material with tin hydroxide deposited on the surface.
[0061] Comparative Example 2
[0062] The difference between this comparative example and Example 2 is that steps (1) and (2) remain unchanged, but step (3) is replaced with:
[0063] (3) The intermediate material obtained in step (2) was dispersed in a mixture of 45 mL ethanol and 5 mL deionized water and reacted at 60 °C for 12 h under nitrogen protection. After the reaction was completed, the mixture was centrifuged, washed with ethanol, and dried under vacuum at 80 °C to obtain a silicon suboxide anode material with an inner layer coated with tin hydroxide and an outer layer coated with 3-mercaptopropyltrimethoxysilane.
[0064] The anode material based on the hierarchical synergistic dynamic reversible buffer layer obtained in Example 1 was subjected to Fourier transform infrared spectroscopy. The resulting spectrum is shown in the figure below. Figure 2 As shown, in the range of 1300~1400 cm -1 The absorption peaks within the range are attributed to BO bonds, proving that the boron source has been successfully introduced into the buffer layer.
[0065] Figure 3 The SEM image and corresponding EDS image of the precursor obtained in step (1) of Example 2 show that tin hydroxide is uniformly deposited on the surface of silicon suboxide particles, and the three elements Si, O and Sn are evenly distributed.
[0066] Application examples
[0067] The electrochemical performance of the silicon-based composite anode material obtained was tested using coin cells. Using the silicon anode materials prepared in the examples and comparative examples as the active material, PAA (polyacrylic acid) was used as a binder, and conductive agent Super P (conductive carbon black) was added in a mass ratio of active material:PAA:super P = 8:1:1. The mixture was then thoroughly stirred to form an anode slurry. The slurry was then uniformly coated onto copper foil, placed in an oven at 80°C for 10 hours, and then rolled and pressed to obtain the anode sheet.
[0068] The prepared negative electrode sheet was used as the negative electrode of a lithium-ion battery, with metallic lithium as the positive electrode material. A polypropylene microporous membrane was used as the separator, and the electrolyte was a 1 mol / L LiPF6 solution of EC (ethylene carbonate) + DEC (diethyl carbonate) in a 1:1 volume ratio. The batteries were assembled into coin cells in an argon-filled glove box, and charge-discharge cycle tests were performed. The batteries were first activated at a current density of 0.1 A / g for 3 cycles before subsequent tests.
[0069] Figure 4The first charge-discharge curve of the battery assembled with the negative electrode material in Example 1 is shown. The first charge specific capacity is 1481.32 mAh / g, the first coulombic efficiency is 70.29%, the electrochemical test charging cutoff voltage is 1.50V, and the discharge cutoff voltage is 0.01V. Figure 5 The graph shows the cycling performance of the battery assembled with the negative electrode material in Example 1 at a current density of 0.5 A / g.
[0070] Figure 6 The graph shows the cycling performance of the battery assembled with the negative electrode material in Example 2 at a current density of 0.5 A / g. The reversible specific capacities after 100 and 200 cycles are 1273.47 mAh / g and 1256.93 mAh / g, respectively, with capacity retention rates of 96.31% and 95.06%, respectively.
[0071] Figure 7 The graph shows the cycling performance of the battery assembled with the negative electrode material in Comparative Example 1 at a current density of 0.5 A / g. After 200 cycles, the capacity retention rate is only 64.26%.
[0072] Figure 8 The graph shows the cycling performance of the battery assembled with the negative electrode material in Comparative Example 2 at a current density of 0.5 A / g. The capacity retention rate after 200 cycles is 81.35%.
[0073] In summary, the silicon-based anode material obtained in this invention exhibits excellent electrochemical performance and stability when applied to lithium-ion batteries. This is due to the construction of a hierarchical synergistic dynamic reversible buffer layer on the surface of the silicon-based material. The inner layer consists of a metal oxide / hydroxide layer as an inner coordination support layer, which provides a strong coordination anchor point for the inverted siloxane end base layer and possesses certain lithium-ion conductivity and structural rigidity, synergistically suppressing volume expansion. The middle layer is a flexible alkyl backbone layer formed by the outward extension of the flexible alkyl backbone of the silane coupling agent. Through conformational changes of the CC single bonds, it achieves first-level stress absorption at the molecular scale, providing rapid and reversible elastic buffering for the volume expansion / contraction of the silicon-based material. The outer layer is a Si-OB dynamic covalent bond network formed by the siloxane end groups of the silane coupling agent and boron-containing compounds. When the stress exceeds the buffer threshold of the alkyl backbone, it achieves second-level stress dissipation through reversible fracture. After stress removal, it self-repairs and rebuilds. The synergistic effect of these two mechanisms fundamentally alleviates the stress concentration problem and avoids permanent damage to the buffer layer.
[0074] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.
Claims
1. A method for preparing a negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer, characterized in that, Includes the following steps: S1. Deposit metal oxides or hydroxides in situ on the surface of silicon-based materials to obtain precursor materials; S2. The precursor material is mixed with a silane coupling agent containing functional groups in an organic solvent. The functional groups undergo a coordination reaction with the metal atoms on the surface of the precursor material to form an elastic siloxane end base layer, thereby obtaining an intermediate material. S3. The intermediate material and the boron-containing compound are mixed in a mixed solvent of water and organic solvent to carry out hydrolysis and dehydration condensation reaction; wherein, the alkoxy group of the silane coupling agent is hydrolyzed and reacts with the boron-containing compound to form a Si-OB dynamic crosslinking network layer, thereby obtaining the negative electrode material based on the hierarchical synergistic dynamic reversible buffer layer.
2. The method for preparing the negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer as described in claim 1, characterized in that, In S2, the functional group is selected from one or more of amino, mercapto, epoxy, and urea groups.
3. The method for preparing the negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer as described in claim 2, characterized in that, In S2, the silane coupling agent is selected from one or more of 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-[3-(trimethoxysilyl)propyl]ethylenediamine, 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, and ureapropyltriethoxysilane.
4. The method for preparing the negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer as described in claim 1, characterized in that, In S3, the boron-containing compound is selected from one or more of boric acid, borax, phenylboronic acid, 1,3-phenyldiboronic acid, 1,4-phenyldiboronic acid, trimethyl borate, and tributyl borate.
5. The method for preparing the negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer as described in claim 1, characterized in that, In S1, the silicon-based material is selected from one or more of silicon, silicon suboxide, and silicon-carbon composite materials.
6. The method for preparing the negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer as described in claim 1, characterized in that, In S1, the metal is selected from one or more of magnesium, aluminum, titanium, iron, cobalt, nickel, copper, zinc, gallium, germanium, zirconium, silver, indium, tin, and antimony.
7. The method for preparing the negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer as described in claim 1, characterized in that, In S2, the reaction temperature is 25-100℃.
8. The method for preparing the negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer as described in claim 1, characterized in that, In S3, the temperature of the hydrolysis and dehydration condensation reaction is 25-200℃.
9. A negative electrode material based on a hierarchical synergistic dynamic reversible buffer layer prepared by the preparation method according to any one of claims 1-8.
10. A lithium-ion battery, characterized in that, Includes the negative electrode material as described in claim 9.