Ion-electron mixed conductor coated silicon-carbon composite material for solid-state battery
By coating silicon-carbon composite materials with ion-electron hybrid conductors, a stable electron conduction network and fast ion channels are constructed, solving the problem of electrode structure collapse caused by the volume expansion of silicon-based materials, and achieving high-efficiency battery performance and long life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG JIAXING XINGHAN NANO TECH CO LTD
- Filing Date
- 2025-12-08
- Publication Date
- 2026-04-28
AI Technical Summary
The theoretical specific capacity of existing commercial graphite anode materials is insufficient. The volume expansion of silicon-based materials during charging and discharging leads to the collapse of the electrode structure and interfacial side reactions, which seriously shortens the cycle life of the battery.
A silicon-carbon composite material is coated with an ion-electron hybrid conductor. A continuous electron conduction network is constructed by carbon, carbon-based materials, conductive polymers, magnesium powder, and zinc nanoparticles. Lithium silicate and organic lithium compounds are combined to form a fast ion channel. The flexible porous structure buffers volume expansion and optimizes interface stability.
Effectively controlling the volume expansion rate ensures the stability of the electrode structure, improves electron and ion conduction efficiency, extends battery cycle life, reduces costs, and meets industrialization needs.
Smart Images
Figure CN121938862A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of lithium battery material preparation technology, specifically to a silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries. Background Technology
[0002] With the rapid development of the new energy industry, solid-state batteries have become the core development direction of next-generation power batteries due to their advantages such as high energy density, good safety, and long cycle life. As a key component of solid-state batteries, the performance of anode materials directly determines the overall efficiency of the battery. Currently, commercially available anode materials are mainly graphite, but its theoretical specific capacity is only 372 mAh / g, which is insufficient to meet the high energy density requirements of solid-state batteries. Therefore, the development of high-capacity anode materials has become a research hotspot in the industry. Silicon-based materials are considered the most promising high-capacity anode candidates due to their theoretical specific capacity of up to 4200 mAh / g (more than 10 times that of graphite) and good intercalation / deintercalation characteristics with lithium ions. However, silicon-based materials experience a 300%-400% volume expansion during charge and discharge, leading to electrode structure collapse and active material shedding. At the same time, an unstable solid electrolyte interphase (SEI) film easily forms on the silicon surface, triggering continuous interfacial side reactions and severely shortening the battery cycle life. To address this, we propose a silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries. Summary of the Invention
[0003] To address the aforementioned technical problems, a silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries is provided. This technical solution solves the problems mentioned above.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a silicon-carbon composite material for solid-state batteries with ion-electron hybrid conductor coating, wherein the silicon-carbon composite material is prepared from the following materials in parts: 10-500 parts silicon, 10-600 parts carbon, 1-450 parts carbon-based material, 10-300 parts conductive polymer, 100-300 parts magnesium powder, 100-400 parts nano zinc powder, 1-120 parts lithium silicate and 1-200 parts organic lithium compound.
[0005] Preferably, the silicon is either nano-silicon powder or porous silicon particles with a particle size of 50-500 nm, the carbon is either amorphous carbon or graphitic carbon, and the carbon-based material is either nitrogen-doped carbon, oxygen-doped carbon, or phosphorus-doped carbon.
[0006] Preferably, the conductive polymer is one of polypyrrole, polyaniline, and polythiophene, with a conductivity of 1-100 S / cm; the magnesium powder is one of spherical magnesium powder, flake magnesium powder, and irregular magnesium powder.
[0007] Preferably, the nano zinc powder is one of spherical nano zinc powder, flake nano zinc powder, and porous nano zinc powder; the lithium silicate is one of lithium monosilicate, lithium disilicate, and lithium orthosilicate; and the organolithium compound is one of lithium bis(oxalato)borate and lithium tetrafluoroborate.
[0008] Preferably, the preparation steps of the composite material are as follows: S1. Preparation of silicon-carbon core layer: Silicon, carbon, and carbon-based materials are added to anhydrous ethanol in a certain proportion and dispersed by ultrasonication to form a suspension; the suspension is transferred to a spray dryer for drying to obtain silicon-carbon composite particles; the silicon-carbon composite particles are calcined at 800-1000℃ for 2-4 hours under an inert gas and cooled to room temperature to obtain silicon-carbon core layer. S2. Preparation of conductive polymer coating layer: The obtained silicon-carbon core layer is added to deionized water and stirred to form a slurry; conductive polymer and oxidant are added and reacted at 25-50℃ for 4-8 h to polymerize the conductive polymer in situ and coat the surface of the silicon-carbon core layer. After filtration, washing and vacuum drying, polymer-coated silicon-carbon particles are obtained. S3. Metal hybrid conductor layer coating: Add the obtained polymer-coated silicon carbon particles to isopropanol and ultrasonically disperse for 20-40 min; add magnesium powder and nano zinc powder, stir under inert gas and then heat to 60-80℃ and keep warm for 2-3 h to obtain metal-coated particles; S4. Ion conductor layer coating: Lithium silicate and organic lithium compound are dissolved in a certain ratio and stirred to form a coating solution; metal coating particles are added to the coating solution and stirred for 1-2 hours; the coating solution is uniformly deposited on the surface of the metal coating particles by atomization deposition method to form an ion conductor coating layer. S5. Anneal the coating layer under an inert gas at 200-300℃ for 1-2 h to remove residual solvent and optimize the crystallinity of the coating layer. After cooling, sieve to obtain the ion-electron hybrid conductor coated silicon-carbon composite material.
[0009] Preferably, in step S1, the ultrasonic power is 300-500W, the ultrasonic time is 30-60min, the ratio of the total mass of silicon, carbon and carbon-based materials to anhydrous ethanol is controlled at 1:5-1:10; the inlet temperature of the dryer is 180℃-220℃, the outlet temperature is 80℃-100℃, and the feeding rate is 5-15mL / min.
[0010] Preferably, in step S1, the atomization pressure of the desiccant drying is 0.2-0.4 MPa, and the inert gas is high-purity nitrogen.
[0011] Preferably, in step S2, the slurry is stirred at a speed of 300-500 rpm for 30-60 min, filtered by vacuum filtration, the filter medium is a 0.22-0.24 μm microporous membrane, and the drying temperature is 60-80℃.
[0012] Preferably, in step S3, the ultrasonic power is 200-300W, the inert gas is argon, and after the ultrasonication is completed, the inert gas is introduced into the reaction vessel for replacement 3-5 times, with a gas flow rate of 100-150 mL / min each time, and the flow rate is maintained at 50-80 mL / min after the replacement is completed.
[0013] Preferably, in step S4, the total mass ratio of lithium silicate and organolithium compound to solvent is 10%-20%, the stirring speed is set to 600-800 rpm, and the mass ratio of metal-coated particles to coating liquid is 1:3-1:5.
[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes the synergistic effect of magnesium powder and conductive polymers to control the volume expansion rate below 50%, ensuring the stability of the electrode structure. Carbon, carbon-based materials, and nano-zinc powder construct an electron conduction network, while lithium silicate and organic lithium compounds form ion conduction channels. The rational proportions and processes solve the compatibility problem of multiple components. Low-activity metals are used to replace high-activity lithium, improving the safety of preparation. Moreover, the raw materials are conventional industrial materials, the process is mature, and it balances performance and cost, meeting the needs of industrialization. Attached Figure Description
[0015] Figure 1 This is a flowchart illustrating the preparation process of the composite material of this invention. Detailed Implementation
[0016] The following description is intended to disclose the invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.
[0017] A silicon-carbon composite material for solid-state batteries with ion-electron hybrid conductor coating, wherein the silicon-carbon composite material is prepared from the following materials in parts: 10-500 parts silicon, 10-600 parts carbon, 1-450 parts carbon-based material, 10-300 parts conductive polymer, 100-300 parts magnesium powder, 100-400 parts nano zinc powder, 1-120 parts lithium silicate, and 1-200 parts organic lithium compound.
[0018] This application constructs a continuous electron conduction network using carbon, carbon-based materials, conductive polymers, and magnesium and zinc powders, combined with lithium silicate and organic lithium compounds to provide fast ion channels, achieving high conductivity for both ions and electrons. The flexible porous structure of carbon-based materials and conductive polymers buffers silicon, and the outer coating layer provides constraint, maintaining the integrity of the electrode structure to improve cycle stability. Lithium ions are released using lithium silicate and organic lithium compounds, and the interface is optimized with magnesium and zinc powders to compensate for lithium loss in solid-state batteries, improving the first coulombic efficiency. Simultaneously, using silicon as a high-capacity base, the silicon content can be adjusted to meet specific needs, and the use of carbon and magnesium powders reduces costs, balancing performance and practicality, thus contributing to the development of solid-state batteries.
[0019] Silicon is one of nano-silicon powder and porous silicon particles; its particle size is 50-500nm. Carbon is one of amorphous carbon and graphitic carbon. Carbon-based materials are one of nitrogen-doped carbon, oxygen-doped carbon and phosphorus-doped carbon.
[0020] The nano-silicon powder in this application disperses volume expansion stress through the small size effect, avoiding cracking caused by excessively large single particles; the porous silicon particles directly buffer expansion through their own pore structure, while increasing the contact area with the conductive network; the particle size range of 50-500nm is key, which retains the stress dispersion advantage of nanomaterials, avoids particle agglomeration caused by excessive fineness, and balances dispersibility and stability.
[0021] The conductive polymer is one of polypyrrole, polyaniline, and polythiophene, with a conductivity of 1-100 S / cm; the magnesium powder is one of spherical magnesium powder, flake magnesium powder, and irregular magnesium powder.
[0022] The nano zinc powder is one of spherical nano zinc powder, flake nano zinc powder, and porous nano zinc powder; the lithium silicate is one of lithium monosilicate, lithium disilicate, and lithium orthosilicate; the organolithium compound is one of lithium bis(oxalato)borate and lithium tetrafluoroborate.
[0023] The preparation steps of the composite material are as follows: S1. Preparation of silicon-carbon core layer: Silicon, carbon, and carbon-based materials are added to anhydrous ethanol in a certain proportion and dispersed by ultrasonication to form a suspension; the suspension is transferred to a spray dryer for drying to obtain silicon-carbon composite particles; the silicon-carbon composite particles are calcined at 800-1000℃ for 2-4 hours under an inert gas and cooled to room temperature to obtain silicon-carbon core layer. S2. Preparation of conductive polymer coating layer: The obtained silicon-carbon core layer is added to deionized water and stirred to form a slurry; conductive polymer and oxidant are added and reacted at 25-50℃ for 4-8 h to polymerize the conductive polymer in situ and coat the surface of the silicon-carbon core layer. After filtration, washing and vacuum drying, polymer-coated silicon-carbon particles are obtained. S3. Metal hybrid conductor layer coating: Add the obtained polymer-coated silicon carbon particles to isopropanol and ultrasonically disperse for 20-40 min; add magnesium powder and nano zinc powder, stir under inert gas and then heat to 60-80℃ and keep warm for 2-3 h to obtain metal-coated particles; S4. Ion conductor layer coating: Lithium silicate and organic lithium compound are dissolved in a certain ratio and stirred to form a coating solution; metal coating particles are added to the coating solution and stirred for 1-2 hours; the coating solution is uniformly deposited on the surface of the metal coating particles by atomization deposition method to form an ion conductor coating layer. S5. Anneal the coating layer under an inert gas at 200-300℃ for 1-2 h to remove residual solvent and optimize the crystallinity of the coating layer. After cooling, sieve to obtain the ion-electron hybrid conductor coated silicon-carbon composite material.
[0024] In step S1, the ultrasonic power is 300-500W, the ultrasonic time is 30-60min, and the ratio of the total mass of silicon, carbon and carbon-based materials to anhydrous ethanol is controlled at 1:5-1:10. The inlet temperature of the dryer is 180℃-220℃, the outlet temperature is 80℃-100℃, and the feed rate is 5-15mL / min.
[0025] In step S1, the atomization pressure of the desiccant is 0.2-0.4 MPa, and the inert gas is high-purity nitrogen.
[0026] In step S2, the slurry is stirred at a speed of 300-500 rpm for 30-60 min. The filtration method is vacuum filtration, with a 0.22-0.24 μm microporous membrane as the filter medium. The drying temperature is 60-80℃.
[0027] In step S3, the ultrasonic power is 200-300W, and the inert gas is argon. After ultrasonication, inert gas is introduced into the reaction vessel for 3-5 replacements, with a gas flow rate of 100-150 mL / min each time. After replacement, the flow rate is maintained at 50-80 mL / min for continuous gas supply.
[0028] In step S4, the total mass ratio of lithium silicate and organolithium compounds to solvent is 10%-20%, the stirring speed is set to 600-800 rpm, and the mass ratio of metal-coated particles to coating liquid is 1:3-1:5. Example 1:
[0029] Prepare the following materials in the following quantities: 500 parts silicon, 400 parts carbon, 450 parts carbon-based materials, 300 parts conductive polymer, 300 parts magnesium powder, 400 parts nano zinc powder, 120 parts lithium silicate, and 200 parts organic lithium compound. The preparation steps of the composite material are as follows: S1. Preparation of silicon-carbon core layer: Silicon, carbon, and carbon-based materials are added to anhydrous ethanol in a certain proportion and dispersed by ultrasonication to form a suspension; the suspension is transferred to a spray dryer for drying to obtain silicon-carbon composite particles; the silicon-carbon composite particles are calcined at 800℃ for 2 hours under an inert gas and cooled to room temperature to obtain a silicon-carbon core layer; S2. Preparation of conductive polymer coating layer: The obtained silicon-carbon core layer is added to deionized water and stirred to form a slurry; a conductive polymer and an oxidant are added and reacted at 50℃ for 4 hours to polymerize the conductive polymer in situ and coat the surface of the silicon-carbon core layer; after filtration, washing, and vacuum drying, polymer-coated silicon-carbon particles are obtained; S3. Metal hybrid conductor layer coating: The obtained polymer-coated silicon carbon particles are added to isopropanol and ultrasonically dispersed for 20 min; magnesium powder and nano zinc powder are added, stirred under inert gas, and then heated to 60℃ and kept at that temperature for 2 h to obtain metal-coated particles; S4. Ion conductor layer coating: Lithium silicate and organic lithium compound are dissolved in a certain ratio and stirred to form a coating solution; metal coating particles are added to the coating solution and stirred for 1 hour; the coating solution is uniformly deposited on the surface of the metal coating particles by atomization deposition method to form an ion conductor coating layer. S5. Anneal the coating layer at 200°C for 1 hour under an inert gas to remove residual solvent and optimize the crystallinity of the coating layer. After cooling, sieve to obtain the ion-electron hybrid conductor coated silicon-carbon composite material. Example 2:
[0030] Prepare the following materials in the following quantities: 400 parts silicon, 300 parts carbon, 250 parts carbon-based materials, 100 parts conductive polymer, 150 parts magnesium powder, 120 parts nano zinc powder, 90 parts lithium silicate, and 90 parts organic lithium compound. The preparation steps of the composite material are as follows: S1. Preparation of silicon-carbon core layer: Silicon, carbon, and carbon-based materials are added to anhydrous ethanol in a certain proportion and dispersed by ultrasonication to form a suspension; the suspension is transferred to a spray dryer for drying to obtain silicon-carbon composite particles; the silicon-carbon composite particles are calcined at 1000℃ for 4 hours under an inert gas and cooled to room temperature to obtain silicon-carbon core layer. S2. Preparation of conductive polymer coating layer: The obtained silicon-carbon core layer is added to deionized water and stirred to form a slurry; conductive polymer and oxidant are added and reacted at 50°C for 5 hours to polymerize the conductive polymer in situ and coat the surface of the silicon-carbon core layer. After filtration, washing and vacuum drying, polymer-coated silicon-carbon particles are obtained. S3. Metal hybrid conductor layer coating: The obtained polymer-coated silicon carbon particles are added to isopropanol and ultrasonically dispersed for 30 min; magnesium powder and nano zinc powder are added, stirred under inert gas, and then heated to 80℃ and kept at that temperature for 3 h to obtain metal-coated particles; S4. Ion conductor layer coating: Lithium silicate and organic lithium compound are dissolved in a certain ratio and stirred to form a coating solution; metal coating particles are added to the coating solution and stirred for 1 hour; the coating solution is uniformly deposited on the surface of the metal coating particles by atomization deposition method to form an ion conductor coating layer. S5. Anneal the coating layer at 300°C for 1 hour under an inert gas to remove residual solvent and optimize the crystallinity of the coating layer. After cooling, sieve to obtain the ion-electron hybrid conductor coated silicon-carbon composite material.
[0031] Comparative Example 1 The existing steps for preparing silicon-carbon composite materials are as follows: Raw material mixing: Mix silicon powder and carbon source at a mass ratio of 1:1 to 1:5, add anhydrous ethanol or deionized water as a dispersant to form a uniform slurry; Wet grinding: High-speed grinding is carried out using a sand mill or planetary ball mill at a speed of 300-500 rpm, a ball-to-material ratio of 10:1, and a grinding time of 24-100 hours to refine silicon particles to the nanoscale. Spray drying: The slurry is atomized and then fed into a spray dryer with an inlet air temperature of 150-250℃ and an outlet air temperature of 100-120℃ to quickly dry and form micron-sized composite particles. High-temperature sintering: Sintering at 600-1100℃ for 2-8 hours in an inert atmosphere (argon or nitrogen) to coat silicon particles with carbon source and form a stable structure; Post-processing: Impurities are removed by crushing, magnetic separation and sieving to obtain the final product.
[0032] Comparative analysis In terms of material system construction, Comparative Example 1 only uses a binary basic combination of silicon powder and carbon source, which has a single material function and can only meet the basic requirements of silicon-carbon composites, but cannot specifically solve the core shortcomings of silicon-carbon composite materials. In contrast, Examples 1 and 2 construct a multi-dimensional synergistic system of silicon, carbon, carbon-based materials, conductive polymers, metal powders and ion conductors: the addition of carbon-based materials can work with silicon and carbon to build a more stable core framework, reserving buffer space in advance for the volume expansion of silicon; the conductive polymer forms an organic and inorganic dual electronic conduction network with magnesium powder and nano zinc powder, which makes up for the deficiency of Comparative Example 1, which only relies on carbon source for conductivity and has low electron transport efficiency; the ion conductor layer composed of lithium silicate and organic lithium compounds is a key component that is completely missing in Comparative Example 1, which can directly improve the migration rate of lithium ions inside the material and lay the foundation for high rate performance. Regarding the refinement and targeting of the preparation process, Comparative Example 1 employs a traditional single process of "mixing, grinding, drying, sintering, and post-treatment," which is crude and lacks precise control over the material structure. Wet grinding takes 24-100 hours, resulting in low production efficiency and a tendency for silicon particles to agglomerate and become uneven in size due to prolonged mechanical action. Subsequent coating with only a carbon source is insufficient to form a uniform and dense protective layer. In contrast, Examples 1 and 2 achieve layer-by-layer optimization of the material structure through a process design of layered coating and step-by-step control. In the first step of preparing the silicon-carbon core layer, ultrasonic dispersion is used instead of the long-term wet grinding of Comparative Example 1. This not only efficiently achieves uniform dispersion of silicon, carbon, and carbon-based materials but also avoids excessive agglomeration of silicon particles. Combined with spray drying and precise baking at 800-1000℃, the process is optimized step by step. The first step, sintering, controls the uniformity of the core layer particle size, laying the foundation for subsequent coating. The second step, conductive polymer coating, uses in-situ polymerization, allowing the conductive polymer to adhere tightly to the silicon-carbon core layer surface, forming a more uniform conductive interface than Comparative Example 1. The third step, metal hybrid conductor layer, uses ultrasonic dispersion and inert gas protection heating to ensure uniform distribution of metal powder on the polymer coating surface, avoiding metal oxidation. The fourth step, ion conductor layer, uses atomization deposition, which, compared to the non-directional carbon source coating in Comparative Example 1, achieves precise and dense coverage of ion conductor components on the metal coating particle surface. Finally, the newly added 200-300℃ annealing step removes residual solvents, optimizes the crystallinity of the coating layer, and further improves structural stability. This is a key post-processing step lacking in Comparative Example 1. In terms of performance optimization, the process design of Comparative Example 1 can only achieve the basic goal of silicon-carbon composite, and cannot solve the core pain points of silicon-carbon materials, such as cycle decay caused by silicon volume expansion and rate capability difference caused by low electron / ion conduction efficiency. In contrast, the process and material designs of Examples 1 and 2 are both centered around these pain points: the multi-layer coating structure forms an integrated protection system for buffering, conductivity, and ion transport. It can effectively buffer the volume expansion of silicon during charging and discharging through the synergistic effect of the core layer framework and each coating layer, and can simultaneously improve electron and ion transport efficiency through a dual electron conduction network and a dedicated ion conductor layer. Moreover, the process parameters of Examples 1 and 2 are more precise, and the structural density and crystallinity can be adjusted according to performance requirements. Compared with the broad sintering parameters of Comparative Example 1, it can more stably ensure batch consistency and performance reliability of products.
[0033] In summary, Examples 1 and 2, through the synergistic design of a multi-material system and the layered and refined process, fundamentally solve the problems of single material function, rough structural control, and prominent performance shortcomings in the traditional process of Comparative Example 1. They are more in line with the actual application requirements of high-performance silicon-carbon composite materials in terms of cycle stability, rate performance, and structural reliability, while also having significant advantages in production efficiency and process controllability.
[0034] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.
Claims
1. A silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries, characterized in that, Silicon-carbon composite materials are prepared from the following components: 10-500 parts silicon, 10-600 parts carbon, 1-450 parts carbon-based materials, 10-300 parts conductive polymer, 100-300 parts magnesium powder, 100-400 parts nano zinc powder, 1-120 parts lithium silicate, and 1-200 parts organic lithium compound.
2. The silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 1, characterized in that: Silicon is one of nano-silicon powder and porous silicon particles; its particle size is 50-500nm. Carbon is one of amorphous carbon and graphitic carbon. Carbon-based materials are one of nitrogen-doped carbon, oxygen-doped carbon and phosphorus-doped carbon.
3. The silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 1, characterized in that: The conductive polymer is one of polypyrrole, polyaniline, and polythiophene, with a conductivity of 1-100 S / cm; the magnesium powder is one of spherical magnesium powder, flake magnesium powder, and irregular magnesium powder.
4. The silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 1, characterized in that: The nano zinc powder is one of spherical nano zinc powder, flake nano zinc powder, and porous nano zinc powder; the lithium silicate is one of lithium monosilicate, lithium disilicate, and lithium orthosilicate; the organolithium compound is one of lithium bis(oxalato)borate and lithium tetrafluoroborate.
5. The silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 1, characterized in that, The preparation steps of the composite material are as follows: S1. Preparation of silicon-carbon core layer: Silicon, carbon, and carbon-based materials are added to anhydrous ethanol in a certain proportion and dispersed by ultrasonication to form a suspension; the suspension is transferred to a spray dryer for drying to obtain silicon-carbon composite particles; the silicon-carbon composite particles are calcined at 800-1000℃ for 2-4 hours under an inert gas and cooled to room temperature to obtain silicon-carbon core layer. S2. Preparation of conductive polymer coating layer: The obtained silicon-carbon core layer is added to deionized water and stirred to form a slurry; conductive polymer and oxidant are added and reacted at 25-50℃ for 4-8 h to polymerize the conductive polymer in situ and coat the surface of the silicon-carbon core layer. After filtration, washing and vacuum drying, polymer-coated silicon-carbon particles are obtained. S3. Metal hybrid conductor layer coating: Add the obtained polymer-coated silicon carbon particles to isopropanol and ultrasonically disperse for 20-40 min; add magnesium powder and nano zinc powder, stir under inert gas and then heat to 60-80℃ and keep warm for 2-3 h to obtain metal-coated particles; S4. Ion conductor layer coating: Lithium silicate and organic lithium compound are dissolved in a certain ratio and stirred to form a coating solution; metal coating particles are added to the coating solution and stirred for 1-2 hours; the coating solution is uniformly deposited on the surface of the metal coating particles by atomization deposition method to form an ion conductor coating layer. S5. Anneal the coating layer under an inert gas at 200-300℃ for 1-2 h to remove residual solvent and optimize the crystallinity of the coating layer. After cooling, sieve to obtain the ion-electron hybrid conductor coated silicon-carbon composite material.
6. The silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 5, characterized in that: In step S1, the ultrasonic power is 300-500W, the ultrasonic time is 30-60min, and the ratio of the total mass of silicon, carbon and carbon-based materials to anhydrous ethanol is controlled at 1:5-1:
10. The inlet temperature of the dryer is 180℃-220℃, the outlet temperature is 80℃-100℃, and the feed rate is 5-15mL / min.
7. The silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 5, characterized in that: In step S1, the atomization pressure of the desiccant is 0.2-0.4 MPa, and the inert gas is high-purity nitrogen.
8. The silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 5, characterized in that: In step S2, the slurry is stirred at a speed of 300-500 rpm for 30-60 min. The filtration method is vacuum filtration, with a 0.22-0.24 μm microporous membrane as the filter medium. The drying temperature is 60-80℃.
9. A silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 5, characterized in that: In step S3, the ultrasonic power is 200-300W, and the inert gas is argon. After ultrasonication, inert gas is introduced into the reaction vessel for 3-5 replacements, with a gas flow rate of 100-150 mL / min each time. After replacement, the flow rate is maintained at 50-80 mL / min for continuous gas supply.
10. A silicon-carbon composite material coated with an ion-electron hybrid conductor for solid-state batteries according to claim 5, characterized in that: In step S4, the total mass ratio of lithium silicate and organolithium compounds to solvent is 10%-20%, the stirring speed is set to 600-800 rpm, and the mass ratio of metal-coated particles to coating liquid is 1:3-1:5.