Effects of carbon coating on calendered nano-silicon graphite composite anodes of LiB

Si/CrSi2 Alloy Anodes Synthesized by a High-Energy Ball-Milling Method for Lithium-Ion Batteries: Microstructure, Electrochemistry, and Carbon Coating

“…The results show that compared to the Si 85 Cr 15 precursor, Si 85 Cr 15 @c-PDA exerts improved 100-cycle capacity retention of 93.1% and slightly reduced ACEs of 99.44% under the current rate of 0.2 C. At the same time, Figure c reveals that the long-term cycle for Si 85 Cr 15 @c-PDA at 0.5 C also performs with good stability with 200-cycle capacity retention of 90.6% and reversible capacity of 799.6 mA h·g –1 . It could be explained that the coated c-PDA layer provides better electrical conductivity for the Si 85 Cr 15 particles, favorable for lowering the capacity loss during cycling . On the other side, the c-PDA layer can further alleviate the whole volume expansion of Si 85 Cr 15 alloys and stabilize the SEI film. , However, the cycle performance modification of mSi@c-PDA is very limited only with the capacity retention of 68.2% after 100 cycles, and the ACEs (98.78%) become much poorer than the one of mSi (98.95%).…”

“…It could be explained that the coated c-PDA layer provides better electrical conductivity for the Si 85 Cr 15 particles, favorable for lowering the capacity loss during cycling . On the other side, the c-PDA layer can further alleviate the whole volume expansion of Si 85 Cr 15 alloys and stabilize the SEI film. , However, the cycle performance modification of mSi@c-PDA is very limited only with the capacity retention of 68.2% after 100 cycles, and the ACEs (98.78%) become much poorer than the one of mSi (98.95%). It is speculated that due to the lack of the CrSi 2 matrix, the amorphous c-PDA layer on the surface of mSi is not robust enough to resist the repeated expansion of internal Si particles.…”

“…45 On the other side, the c-PDA layer can further alleviate the whole volume expansion of Si 85 Cr 15 alloys and stabilize the SEI film. 12,45 However, the cycle performance modification of mSi@c-PDA is very limited only with the capacity retention of 68.2% after 100 cycles, and the ACEs (98.78%) become much poorer than the one of mSi (98.95%). It is speculated that due to the lack of the CrSi 2 matrix, the amorphous c-PDA layer on the surface of mSi is not robust enough to resist the repeated expansion of internal Si particles.…”

Tailored Silver Nanowires for Amplified Lithium-Ion Battery Performance and Inhibition of Lithium Dendrites in Silicon–Graphite–Silver Nanowire Composite Electrodes

“…At the same time, in Si based electrodes, it is important to consider the design of the electrode microstructure to accommodate the expansion of Si by providing voids or pores. Performing the calendaring process on the Si@Gr/C electrode increases electrode density and reduces the theoretical porosity by up to 50% (66.2–33.2%) . Additionally, the pore size distribution narrows and shifts toward smaller pores, potentially causing Si nanoparticles to block the pores of Gr and lose contact.…”

Efficient Utilization of Macropores as Artificial Solid–Electrolyte Interphase Channels for High-Capacity Silicon/Graphite Anode Materials

“…Nano Si particles (particle size <150 nm) are reported to be fracture-proof upon lithiation. Hence the combination of nano Si with micron-sized graphite particles is found to be an ideal mixture as Si/Gr composites can also benefit from a high electrode density owing to the micron-sized graphite particles. − Furthermore, graphite acts as a buffering agent when Si particles get dilated. There is a growing interest toward the preparation of Si/Gr composites with different capacities over time.…”