A high-quality mechanofusion coating for enhancing lithium-ion battery cathode material performance
- PDF / 659,889 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 92 Downloads / 336 Views
Research Letter
A high-quality mechanofusion coating for enhancing lithium-ion battery cathode material performance Lituo Zheng, and T.D. Hatchard, Department of Chemistry, Dalhousie University, Halifax, N.S., B3H 4R2, Canada M.N. Obrovac, Department of Chemistry, Dalhousie University, Halifax, N.S., B3H 4R2, Canada; Department of Physics, Dalhousie University, Halifax, N.S., B3H 4R2, Canada Address all correspondence to M. N. Obrovac at [email protected] (Received 24 July 2018; accepted 24 September 2018)
Abstract Lithium (Li)-ion battery cathode materials are typically coated to improve cycling performance, using aqueous-based coating techniques that require filtering, drying, and even sintering of the final product. Here, spherical LiNi0.6Mn0.2Co0.2O2 particles were coated with nano-Al2O3 using the dry mechanofusion method. This method produced a durable, non-porous Al2O3 coating that is retained during slurry making. Mechanofusion coatings significantly improved Li-ion battery cathode cycling at high voltages, enabling high energy densities, while offering inexpensive, scalable, and environmentally friendly solvent-free synthesis. This opens up new possibilities, since, not being limited by synthesis chemistry, mechanofusion can in principle be used to apply any coating material.
Green and renewable energy resources, such as wind or solar energy, are usually intermittent and unstable. Therefore, large scale energy storage systems are needed for load-leveling. Rechargeable battery technology is promising to play a vital role in electric grid energy storage. Applications of lithium-ion batteries in electric vehicles or grid energy storage applications require long battery lifetimes.[1] Various approaches have been shown to improve the cycle life of lithium-ion batteries, such as the use of electrolyte additives or modification of cathode material composition.[2,3] Electrolyte deterioration is one of the causes of capacity fade.[4] The aging of an electrolyte mainly occurs on electrode surfaces.[5] Therefore, surface chemistry plays a crucial role in cycling performance. As reported by many researchers, surface coating of cathode material particles is an effective way to improve long-term cycling performance.[6,7] Metal oxides are the most commonly used materials to coat positive electrode material particles.[8,9] There are multiple possible mechanisms that lead to the improvement observed when cathode particles are coated with metal oxides. Xiong et al. showed that an Al2O3 coating suppresses impedance growth of layered Li[NixMnyCoz]O2 cathodes and improves coulombic efficiency and capacity retention.[10] Kim et al. compared the effect of different metal oxide coatings (ZrO2, Al2O3, TiO2, etc.) on LiCoO2 and concluded that oxide coatings can suppress cobalt dissolution, resulting in improved cycling behavior.[7] Interestingly, Chen et al. compared the behavior of heated LiCoO2 and oxide-coated LiCoO2, and observed a similar cycling performance.[11,12] They proposed that it is the heat treatment, not the presence of t
Data Loading...
