Tuning Oxygen Redox Chemistry in Li-Rich Mn-Based Layered Oxide Cathodes by Modulating Cation Arrangement

Authors

Jicheng Zhang, Nankai University
Fangyi Cheng, Nankai University
Shulei Chou, University of WollongongFollow
Jian Li Wang, University of WollongongFollow
Lin Gu, Chinese Academy of Sciences
Heng Wang, Zhengzhou University of Light Industry
Hirofumi Yoshikawa, Kwansei Gakuin University
Yong Lu, Nankai University
Jun Chen, Nankai University

RIS ID

138705

Publication Details

Zhang, J., Cheng, F., Chou, S., Wang, J., Gu, L., Wang, H., Yoshikawa, H., Lu, Y. & Chen, J. (2019). Tuning Oxygen Redox Chemistry in Li-Rich Mn-Based Layered Oxide Cathodes by Modulating Cation Arrangement. Advanced Materials, 31 (42), 1901808-1-1901808-7.

Abstract

Li-rich Mn-based oxides (LRMO) are promising cathode materials to build next-generation lithium-ion batteries with high energy density exceeding 400 W h kg−1. However, due to a lack of in-depth understanding of oxygen redox chemistry in LRMO, voltage decay is not resolved thoroughly. Here, it is demonstrated that the oxygen redox chemistry could be tuned by modulating cation arrangement. It declares that the materials with Li/Ni disorder and Li vacancies can inhibit the formation of OO dimers. Because of the high chemical activity, OO dimers could accelerate lattice oxygen release and NiO/spinel formation. The samples without forming OO dimers show improved performance in suppressing oxygen overoxidation and mitigating cation dissolution. As a result, the optimized cathode exhibits a high capacity over 280 mA h g−1 at 0.1 C and a high plateau voltage of 3.58 V with a very low voltage decay of 1.6% after 150 cycles at 1 C. This study opens an attractive path in designing Li-rich electrodes with stabilized redox chemistry.