Enhanced Electrochemical Performance of Graphite Anodes for Lithium-Ion Batteries by Dry Coating with Hydrophobic Fumed Silica

Abstract

Coating of electrode materials for lithium-ion batteries is usually performed in order to improve performance, safety and the processability of the raw material. Here, we apply a dry coating method of graphite with hydrophobic fumed silica particles. This method excludes the use of any harmful solvents and the nano-scale particles cover and stick to the graphite substrate by only adhesive forces. Furthermore, this dry coating method is easily mass-scalable and a high throughput can be obtained in a short processing time. The nanoparticle coating reduces the van-der-Waals forces between the graphite particles and leads in this way to better flowability of the graphite powder which is important for further processing and the production of electrode tapes. Furthermore, these core-shell particles were processed to composite negative graphite electrodes in combination with the water soluble binder sodium carboxy-methylcellulose. Electrodes obtained with the coated material displayed a smooth surface, a high mechanical stability and outperformed the unmodified ones in the electrochemical investigations.

Nitrile functionalized silyl ether with dissolved LiTFSI as new electrolyte solvent for lithium-ion batteries

“…The Coulombic efficiency is 87.9 % for the first cycle and reaches values > 99% after the third cycle. This is in accordance to the literature [37]. In Fig.…”

Electrolytes and Interphases in Li-Ion Batteries and Beyond

“…289 Although little effect was observed in the electrochemical behavior during the initial cycles, long-term stability of graphitic anodes was obtained when 14 nm silica particles were applied to graphite via a dry-coating protocol.…”

A novel process route for the production of spherical SLS polymer powders

“…to improve powder flowability by an increase of surface roughness [6][7][8]. In dry particle coating, nanoscale guest particles are attached to the surface of micron-sized host particles by van der Waals forces.…”

“…In the second step, the irregular shaped particles obtained by wet grinding are rounded in a heated downer reactor. The flowability of the thus obtained rounded product particles is further increased by adhering nanoparticles onto their surface by dry particle coating [6][7][8]. The increase of powder flowability along the process chain has been monitored by tensile strength measurements [9].…”