FAYETTEVILLE, Ark. (KNWA/KFTA) — A University of Arkansas professor has received a grant from the U.S. Department of Energy to aid in developing lithium-ion batteries.
The university announced Friday that mechanical engineering professor Xiangbo “Henry” Meng has received a grant of $750,000 to reconstruct a clean, anti-oxidative surface of high-capacity NMC811 cathodes for the batteries, which are used in battery-powered electric vehicles
“By addressing daunting problems related to the performance of NMC811, a lithium nickel manganese cobalt oxide, the research will improve the energy density, lifetime, and efficiency of lithium-ion batteries, while also reducing their cost,” the university said.
The high nickel content makes NMC811 particularly vulnerable with performance degradation and safety risk in applications. To address these issues, surface modification remains an important safety strategy and has proven effective. We are the first to discover that sulfides as surface coatings can play some unique roles in addressing NMC811 issues. Our work will hopefully deliver technical solutions while advancing our understanding of the electrochemistryAssociate Professor Xiangbo Meng
The university says the high nickel content makes NMC811 cost-effective but also challenging for commercialization due to residual lithium compounds on the surface, structural instability, metal dissolution, microcracking, and oxygen release. These can cause “battery gassing, electrode degradation and other serious performance issues.”
The release notes that Meng specializes in “atomic layer deposition,” a precise, thin-film technique to coat NMC811 electrodes. Atomic layer deposition reportedly enables the coatings to be applied layer by layer at the atomic level. Meng can fine-tune the interface of NMC811 electrodes with a series of novel, sub-nano to nanoscale sulfide coatings to achieve the best battery performance.
According to the U of A, preliminary studies demonstrated that sulfide coatings, via atomic layer deposition, removed residual lithium compounds to form a clean surface and improved electrode stability. The coatings also consumed released oxygen to protect electrolytes from decomposition and acted as an interfacial layer to prevent microcracking and metal dissolution.
For this project, the university says Meng will collaborate with researchers from Argonne National Laboratory and Brookhaven National Laboratory, who will use electron microscopies and synchrotron-based techniques to investigate the underlying mechanisms of sulfide coatings of NMC811.