The key role of zirconia ceramic beads in the production process of silicon carbon negative electrode, especially in nanometer and surface modification.
With the popularity of electric vehicles and portable electronic devices, the demand for high energy density batteries is increasing. Silicon carbon anode material has attracted much attention because of its advantages of high capacity and low cost, and has become the focus of research and application. In this paper, the main production methods of silicon carbon anode and their advantages and disadvantages are introduced in detail, and the key role of zirconia ceramic beads in the production process of silicon carbon anode is deeply discussed, especially the prominent role in nano and surface modification.
First, the production method of silicon carbon anode materials
1.1 Chemical Vapor Deposition (CVD) Chemical vapor deposition uses a gaseous chemical reaction to produce a thin film on the surface of the substrate. In the production of silicon carbon anode materials, the CVD method decomposes silicon source gases such as silane at high temperature and deposits silicon carbon composite materials on the surface of carbon-based materials.
Advantages:
· High purity: CVD method can control the reaction conditions to generate high-purity silicon carbon composite materials.
· Good uniformity: By precisely controlling the reaction parameters, uniform silicon-carbon composites can be obtained.
Cons:
· High cost: high equipment and reaction conditions require high production costs.
Complex equipment: Complex gas phase reaction equipment is required, which requires high requirements for operators.
1.2 Mechanical alloying method Mechanical alloying method uses high-energy ball milling technology to mix silicon and carbon materials and form alloys under the action of mechanical forces. This method is often used to prepare nanostructured silicon-carbon composites.
Advantages:
· Lower cost: Compared with CVD method, mechanical alloying method has lower equipment cost.
· Simple operation: no complex reaction equipment is required, and the operation is relatively simple.
Cons:
· Uneven particle size: The particle size of the silicon carbon composite material generated under the action of mechanical forces may be uneven.
Low purity: Due to the possible introduction of impurities in the mechanical alloying process, the material purity is relatively low.
The role of zirconia ceramic beads in mechanical alloying
In the mechanical alloying process,EVERGRINDING ZY6.0 zirconia ceramic beads are used as grinding media, which can significantly improve the grinding efficiency and the uniformity of the final product. EVERGRINDING ZY6.0（Pro）Zirconia ceramic beads have high hardness, toughness and wear resistance, and can provide higher impact and shear forces during ball milling, thus accelerating the uniform mixing and alloying of silicon and carbon materials. In addition, zirconia ceramic beads have high chemical stability, can avoid the introduction of impurities, and improve the purity of the product.
1.3 Solution method The silicon carbon composite material is prepared by the reaction in chemical solution.
Common solution methods include sol-gel method and coprecipitation method.
Advantages: ·
Easy to control: the composition and structure of the material can be controlled by adjusting the solution composition and reaction conditions.
Low temperature process: Compared with the CVD method, the solution method can be carried out at a lower temperature.
Cons:
· Complex post-treatment: post-treatment processes such as drying and calcination are required.
· Poor uniformity: the solution reaction process may result in uneven material distribution.
1.4 Thermal evaporation method The thermal evaporation method evaporates the material by heating and forms a thin film on the condensing surface. In the production of silicon carbon anode materials, it is often used to prepare nano-silicon particles and carbon-based composites.
Advantages:
· High purity: It can be carried out under vacuum conditions to reduce the introduction of impurities.
· Good uniformity: a uniform film material can be obtained.
Cons:
· High equipment requirements: high vacuum equipment and precision temperature control system are required.
· High cost: high cost of equipment and operation.
Second, the advantages and disadvantages of silicon carbon anode materials
2.1 Advantages:
The theoretical specific capacity of the high-capacity silicon carbon anode material can reach 4200mAh/g, which is much higher than the traditional graphite anode material (about 372mAh/g). This property makes the silicon carbon anode material have great potential in improving the energy density of batteries.
The reserves of low-cost silicon are abundant and the price is relatively low, and the use of silicon carbon anode materials can effectively reduce the cost of batteries. In addition, the preparation process of silicon carbon anode material is relatively simple and suitable for large-scale production.
2.2 Cons:
Disadvantages Volume expansion silicon carbon anode material will have a large volume change during the charge and discharge process, resulting in the instability of the electrode structure, thus affecting the cycle life of the battery. This is an important problem to be solved in the application of silicon carbon anode materials.
Silicon carbon anode materials with low first coulomb efficiency will consume a large amount of lithium ions during the first charge and discharge, resulting in low first coulomb efficiency. This affects the initial capacity of the battery and requires improving the first coulomb efficiency through improved materials and processes.
Third, the application of zirconia beads in the improvement process of silicon carbon anode materials
3.1 Nanometer treatment The effect of the volume expansion on the electrode structure can be effectively reduced by nanizing the silicon material. Nano-silicon particles have large specific surface area, which is helpful to improve the cycling performance of the electrode. In the nano treatment process, zirconia ceramic beads can significantly improve the grinding efficiency and the degree of nanometer product. The high hardness and toughness of zirconia ceramic beads can provide a stronger grinding force to crush the silicon material into nanoscale particles while ensuring the uniformity and purity of the particles.
3.2 Surface modification Surface modification of silicon carbon anode materials, such as coating carbon materials or introducing conductive polymers, can improve the conductivity and structural stability of the materials, thereby increasing the cycle life of the battery. In the surface modification process, zirconia ceramic beads as grinding media can help achieve a more uniform coating effect. Its high hardness and chemical stability ensure that no impurities are introduced during the grinding process, while improving the uniformity and modification effect of the material.
3.3 Composite Structure design Reasonable design of silicon-carbon composite structures, such as core-shell structure, porous structure, etc., can alleviate the volume expansion problem and improve the overall performance of materials. When designing composite structures, zirconia ceramic beads can be used to crush and mix different materials to achieve a uniform composite effect. Its high hardness and wear resistance ensure the purity and uniformity of the material during grinding, thus contributing to the formation of a stable composite structure.
The importance of silane in the field of new energy Silane plays a key role in the crystalline silicon solar cell, flat panel display and semiconductor industries. It is one of the indispensable raw materials in the manufacturing process of new silicon anode materials, and nano silicon particles formed by thermal cracking deposition are the core of new silicon carbon technology. With the growing demand for energy density in the lithium industry, traditional graphite anode materials and high-nickel ternary anode materials have approached their performance limits. In this context, silicon-based negative electrode materials have attracted much attention and are considered by the market as the next generation of mainstream negative electrode materials.
Fourth, safety production warning of silicon-based negative electrode materials - silane gas leakage
The importance of silane in the field of new energy
Silane plays a key role in the crystalline silicon solar cell, flat panel display and semiconductor industries. It is one of the indispensable raw materials in the manufacturing process of new silicon anode materials, and nano silicon particles formed by thermal cracking deposition are the core of new silicon carbon technology. With the growing demand for energy density in the lithium industry, traditional graphite anode materials and high-nickel ternary anode materials have approached their performance limits. In this context, silicon-based negative electrode materials have attracted much attention and are considered by the market as the next generation of mainstream negative electrode materials.
As a new generation of high performance lithium ion battery cathode material, silicon carbon anode material has broad application prospects. Through continuous improvement of the production process and material structure, the superior properties of silicon carbon anode materials will be further developed. However, the problems of volume expansion and low first coulomb efficiency still need to be solved further. The application of zirconia ceramic beads in the production of silicon carbon negative electrode provides an effective means to improve the uniformity, purity and modification effect of products, especially in nanometer and surface modification. With the development of science and technology, we believe that silicon carbon anode materials will play a more important role in the future battery industry.