Effect of Post-synthesis Processing on the Electrochemical Performance of Y2W3O12

Abstract

Lithium-ion batteries (LIBs) are enabling the uptake of electric vehicles and providing grid-scale storage solutions for renewable energy generation. However, it is vital to develop new and advanced electrode materials for lithium-ion batteries to meet various applied considerations such as cost, safety, toxicity, and performance. Here, solid-state synthesized Y2W3O12 is demonstrated as a high-rate active anode material in lithium-ion batteries, producing an initial discharge capacity of 637 mAh/g although with a very poor initial Coulombic efficiency of 35%. To improve the performance, simple post-synthetic milling and carbon coating are investigated. Carbon coating of the material leads to significant performance enhancement in both the unmilled and milled samples. For instance, the unmilled carbon coated electrodes maintained a high capacity of ∼140 mAh/g at 1600 mA/g after 2000 cycles with no capacity fading from cycle 200 to 2000. Such a remarkable rate performance and an excellent long-term cycling stability showcase the great potential of this unconventional electrode material in fast-charge and high-power applications. This facile post-synthesis process can be easily applied to other electrode material candidates to enhance their electrochemical performance.