Research Progress on Coating Structure of Silicon Anode Materials for Lithium‐Ion Batteries

Abstract

Silicon, which has been widely studied by virtue of its extremely high theoretical capacity and abundance, is recognized as one of the most promising anode materials for the next generation of lithium‐ion batteries. However, silicon undergoes tremendous volume change during cycling, which leads to the destruction of the electrode structure and irreversible capacity loss, so the promotion of silicon materials in commercial applications is greatly hampered. In recent years, many strategies have been proposed to address these shortcomings of silicon. This Review focused on different coatings materials (e. g., carbon‐based materials, metals, oxides, conducting polymers, etc.) for silicon materials. The role of different types of materials in the modification of silicon‐based material encapsulation structure was reviewed to confirm the feasibility of the protective layer strategy. Finally, the future research direction of the silicon‐based material coating structure design for the next‐generation lithium‐ion battery was summarized.

Direct-Contact Prelithiation of Si–C Anode Study as a Function of Time, Pressure, Temperature, and the Cell Ideal Time

“…Lithium-ion batteries (LIB) with high energy density have already received great attention in the commercial market. , The demand for high-energy LIB for electric vehicles (≥60–70 kWh to reach 300 miles) has pushed the research to develop next-generation battery materials. − Many investigations have been carried out in the field of silicon and silicon–carbon-based composite anode material due to its higher specific capacity (∼4200 mAh g –1 , Li 4.4 Si), low cost, low working potential, and environmental benignity. − However, Si anode has several limitations such as low initial Coulombic efficiency (ICE) (∼25 to 70%, depending upon the Si composition and structure) and very high volume expansion (300–400%) of Si particles during continuous charging and discharging. ,, Researchers have used Si nanoparticles, nanorods, and nanowires to overcome the expansion problems, and have been partially successful. − However, nano-Si with a high surface area to volume ratio is highly reactive in the presence of the electrolyte, resulting in electrolyte degradation during cycling . Mixing of Si with additive carbon is another approach to minimize the volume expansion problem, and carbon can provide an electrical percolation network for better conductivity .…”

Interlaced CoOx Nanosheets Composited with Reduced Graphene Oxide and Carbonized Bacterial Cellulose as Anode Materials for Lithium‐ion Batteries

“…Therefore, it is highly desirable to develop alternative anode materials that fulfill the requirements of higher energy density and better rate performance. [6][7][8][9][10] Owing to the high specific capacity and large redox capacitance contribution, cobalt oxide-based materials have attracted tremendous attention as the promising candidates. However, the practical application of cobalt oxide-based materials is largely hindered by their intrinsic poor electrical conductivity and severe volume changes of the bulk material upon repeated Li + intercalation/ deintercalation.…”

The Effect of Silicon Grade and Electrode Architecture on the Performance of Advanced Anodes for Next Generation Lithium-Ion Cells

“…In frame of the cell generation 3b concept, silicon (Si) is expected to be added to graphite composite anodes. As an anode material, silicon has a high theoretical capacity of 3579 mAh/g at room temperature (under formation of Li 15 Si 4 ) and a potential against Li/Li+ of 0.4 V [3]. As silicon undergoes a large volume change of about 280% while cycling, the cycle stability and capacity retention are low [4].…”

“…Therefore, the ongoing formation of solid electrolyte interface (SEI) on the freshly exposed surface can be reduced and the consumption of electrolyte can be minimized. Several researchers have also utilized other approaches to incorporate silicon in electrodes by using specialized structures, for example with a yolk-shell structure [7,8], nanowires [9][10][11], hollow nanoparticles [12,13], or other more sophisticated setups [14] as well as by using different coatings [15]; however, the utilization of these materials and compositions in an industrial scale would be cost-intensive, which is why the use of "simple" nanoparticles is preferred.…”