Preparation of Silicon-Carbon Composite Material for Lithium Battery Cathode Material

Preparation of Lithium Battery Cathode Material Silicon Carbon Composite Material Due to its long service life and high efficiency, lithium batteries are increasingly used in large-capacity storage devices such as electric vehicles, energy storage devices, and mobile devices. The following strategies can improve the energy density of lithium batteries (Whu003dkg): 1) change the electrode data; 2) improve the coating process; 3) improve the filling data of the positive electrode and the negative electrode; 4) increase the lithium ion absorption rate of the negative electrode. However, alternative methods 2-4 are generally limited to the optimization of internal space and planning. Therefore, research on the composition of new electrode data is actively being carried out. Currently, the most representative cathode material is graphite. Due to the uniaxial orientation of the graphene layer, it exhibits a highly reversible charge-discharge behavior and therefore has a long cycle life. In addition, when the graphite is fully charged, that is, lithium ions are present between the layers, the electrode potential is 0VvsLiu003dLi+. This indicates that graphite can exhibit a potential similar to that of pure lithium metal. Therefore, a higher energy can be obtained by assembling a battery with a graphite cathode and an oxide anode. However, considering the demand for large-capacity batteries at that time, the theoretical capacity of graphite is relatively low (372mAhu003dg, 837mAhu003dcm3), which is a key obstacle to the continued use of graphite as an anode material. Therefore, in order to develop high-capacity, high-performance lithium secondary batteries, the development of non-carbon anode data is essential. Among these non-carbon hypotheses, Si is the most suitable because it has a high discharge capacity of 4200mAhu003dg and a lithium response potential of 0.4v (vsLiu003dLi+). However, Si encounters a key problem, that is, the volume changes drastically during charging and discharging, which leads to reversibility and capacity-sensitive attenuation. Many methods have been proposed to reduce volume expansion, such as the nano-scale reaction of metal particles to lithium, the composition of heterogeneous alloys that react with lithium, and the composition of activeu003dinactive metal complexes and lithiumu003dcarbon composite materials. No. 11-15) In this study, we tried to deal with the bulk expansion of silicon through the synthesis data of Si-CB. The CB structure is formed by the aggregation of primary particles in different directions. In the CB aggregation, a network of different directions and spaces is formed due to the random rise. 16-19) Therefore, in the case of volume expansion, these spaces will be used as a buffer containing silicon. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Development and future of lithium batteries