Nano‐/Microstructured Si/C Composite with High Tap Density as an Anode Material for Lithium‐Ion Batteries

Abstract

Nanostructured Si materials are plagued by having a limited electrochemical performance and low tap density. Hence, we synthesized a nano‐/microstructured Si/C composite with Si nanoparticles uniformly embedded into a carbon matrix, which had a tap density 5.3 times higher than that of Si nanoparticles. The nano‐/microstructured Si/C composite shows a superior structural stability, which ensures a long cycle life with a capacity of 600 mAh g−1 after 1000 cycles at 420 mA g−1. Moreover, the carbon matrix can provide three‐dimensional electron‐transfer pathways for Si nanoparticles to improve the electronic conductivity. Therefore, the Si/C composite anode material also exhibits an outstanding rate capability, which can still deliver a capacity of 510 mAh g−1 at 5 C. Thus, the nano‐/microstructured Si/C composite with a high tap density possesses great potential in view of practical applications.

Improving the Performance of SiOx/Carbon Materials for High Energy Density Commercial Lithium‐Ion Batteries Based on Montmorillonite

“…In addition, the processing property of the material has an important influence on its electrochemical performances. If the particle size of the material is too low, the high surface energy will cause the particles merge together during lithium ions insertion/extraction process, further resulting in electrochemical sintering and limiting their applicability . The high specific surface area also tends to induce harmful interface reaction, which leads to excessive growth of SEI film and low initial coulombic efficiency .…”

“…Moreover, materials with smaller particle sizes deserved lower tap density, which translates to low volumetric energy density and is very unfavorable for the development of high energy density batteries . Thus, materials applied in LIBs should meet a certain size and specific surface area requirement, so that a battery with the higher energy density can be achieved by coating more active materials in fewer electrodes’ plates via the compacting process . Nevertheless, this issue was rarely concerned about in most literatures.…”

Metal–Organic Frameworks‐Derived Mesoporous Si/SiOx@NC Nanospheres as a Long‐Lifespan Anode Material for Lithium‐Ion Batteries

“…Liu et al. fabricated a Si/C nanohybrid involving voids as the anode material . In addition, SiO x ‐based anode materials have been also used as a structural buffer to accommodate the volume variation and achieve stable cycling performance .…”

A simple method for industrialization to enhance the tap density of LiNi0.5Co0.2Mn0.3O2cathode material for high-specific volumetric energy lithium-ion batteries

“…For instance, some works make efforts to enhance capacity of anode materials via the nanocrystallization technique, but it will bring about negative impacts such as reducing tap density and volume energy density. [5][6][7] One can imagine that cathode materials will also face the same negative situation using this technique.…”