Understanding Co roles towards developing Co-free Ni-rich cathodes for rechargeable batteries

• Published in: Nature energy Vol. 6; no. 3; pp. 277 - 286
• Main Authors: Liu, Tongchao, Yu, Lei, Liu, Jiajie, Lu, Jun, Bi, Xuanxuan, Dai, Alvin, Li, Matthew, Li, Maofan, Hu, Zongxiang, Ma, Lu, Luo, Duan, Zheng, Jiaxin, Wu, Tianpin, Ren, Yang, Wen, Jianguo, Pan, Feng, Amine, Khalil
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-03-2021; Nature Publishing Group
• Subjects: 639/301/299; 639/4077/4079/891; 639/638/161; Batteries; Cathodes; Cobalt; Economics and Management; Electrode materials; Energy; Energy Policy; Energy Storage; Energy Systems; Lithium; Lithium-ion batteries; Manganese; Materials substitution; Nickel; Rechargeable batteries; Reduction; Renewable and Green Energy; Structural stability; Sustainable development
• ISSN: 2058-7546; 2058-7546
• DOI: 10.1038/s41560-021-00776-y

Current bottlenecks in cobalt (Co) supply have negatively impacted commercial battery production and inspired the development of cathode materials that are less reliant on Co. However, complete Co elimination is prevented by the lack of fundamental understanding of the impact of Co on cathode capacity and structural stability, as well as the lack of effective substitute components in practice. Here we investigate the roles of Co in purposely designed systems that include both Co-rich and Mn-substituted Co-free cathodes. Our results affirmed that Co plays an undeniable role in fast capacity and/or structural degradation, and found that Co is more destructive than Ni at high potentials, which offers unexpected but encouraging perspectives for Co reduction. Moreover, Mn substitution effectively alleviates the destructive effects of Co and enables a high potential functionality. With these fundamental discoveries, we demonstrated a series of LiNi
α
Mn
β
X
γ
O
2
(X = single or multiple dopants) as a promising candidate for Co-free cathodes.
Reduction on cobalt reliance is an urgent requirement in the development of sustainable cathode materials for Li-ion batteries. Here the authors analyse the roles of cobalt and its interplay with other ions in high-nickel layered oxides, and deduce a material formula for promising cobalt-free cathodes.