Search

A VOx-impregnated oxide cathode for lithium ion batteries exhibits a substantial drop in oxygen evolution during high voltage operation. An electrolyte was found to catalyze the gas evolution, and the VOxlayer could protect the cathode oxide surface from the electrolyte and stabilize the surface oxide ions during their electrochemical oxidation. [ABSTRACT FROM AUTHOR]

Lithium-rich disordered rocksalt Li2TiS3 offers large discharge capacities (>350 mAh·g−1) and can be considered a promising cathode material for high-energy lithium-ion battery applications. However, the quick fading of the specific capacity results in a poor cycle life of the system, especially when liquid electrolyte-based batteries are used. Our efforts to solve the cycling stability problem resulted in the discovery of new high-energy selenium-substituted materials (Li2TiSexS3−x), which were prepared using a wet mechanochemistry process. X-ray diffraction analysis confirmed that all compositions were obtained in cation-disordered rocksalt phase and that the lattice parameters were expanded by selenium substitution. Substituted materials delivered large reversible capacities, with smaller average potentials, and their cycling stability was superior compared to Li2TiS3 upon cycling at a rate of C/10 between 3.0–1.6 V vs. Li+/Li. [ABSTRACT FROM AUTHOR]