To keep pace with the increasing demands of the electronics industry and the growing popularity of electric vehicles, scientists must continue to innovate and develop highly advanced battery technologies.
One particularly promising avenue is the use of nickel-rich layered oxides as cathode materials in lithium-ion batteries (LiBs).
These Ni-rich cathodes offer a range of potential benefits, such as increased battery capacity, improved charging rates, and lower production costs. However, research has also revealed their limitations, including capacity loss and structural instability during fast charging and long-term cycling.
In response, researchers from Argonne National Laboratory and other institutions around the world have proposed a new strategy to enhance the stability and reliability of
According to the researchers, the surface reconstruction and resulting
To tackle this challenge, Chen Zhao, Chuanwei Wang, and their colleagues designed a specialized oxide coating that aligns with the structure of Ni-rich cathodes. In addition to boosting the durability of the cathode surfaces, these coatings also improve ionic conductivity, facilitating faster charging of batteries.
The coating is based on
- Wadsley-Roth crystallographic shear phases
- a type of compound known to enhance the performance of LiB electrodes
- Remarkably, these compounds exhibit strong adhesion to Ni-rich cathodes, further strengthening their structural stability during use.
"The high tolerance to cracking and corrosion, as well as the rapid ionic transport provided by the entropy-assisted surface, significantly improve the charging/discharging capabilities, temperature range, and thermal stability of
Through a series of experiments, the team tested their proposed coating strategy by applying it to Ni-rich layered cathodes and evaluating their performance over time and under various conditions. The results were highly promising, demonstrating a significant reduction in cathode damage, even during rapid charging and after numerous operation cycles.
"We believe that this epitaxial entropy-assisted coating strategy will lead to new opportunities for surface engineering and the development of high-energy and high-power LiBs and beyond," the researchers concluded.