High energy rechargeable lithium batteries (RLBs) continue to be the most favorite choice for vehicle electrification [1]. Among all cathode active materials, layered transition metal oxides containing nickel (Ni), manganese (Mn), or cobalt (Co), remain the most desired to improve energy density and performance [2]. As the current electrolyte system restricts high voltage operation, new cathode active materials with higher capacity are being sought today. How to seek a better cathode active material needs some better guidance as well. Here, a new perspective on the layered transition metal oxide cathode active materials is proposed based on our recent analysis of the performance characteristics of these current cathode active materials that were evaluated or reported in the literature. This new perspective is supposed to provide a more coherent framework to explain their commonality of the performance in realizing higher capacity within the same stability range. With this perspective, the principle of seeking a better cathode active material could be improved with this understanding.

References:

1. Bao, Y. Cui, E. Dufek, J. Goodenough, P. Khalifah, Q. Li, B.Y. Liaw, A. Manthiram, Y.S. Meng, et al. “Pathways for practical high-energy long-cycling lithium metal batteries.” Nat. Energy 4 (2019) 180–186. https://doi.org/10.1038/s41560-019-0338-x.
2. A. Manthiram. Reflection on lithium-ion battery cathode chemistry. Nat. Commun. 11 (2020) 1550. https://doi.org/10.1038/s41467-020-15355-0.