| Affiliation: | 1. Materials Science and Engineering Program, Texas Materials Institute, University of Texas at Austin, Austin, TX 78712 USA Contribution: Conceptualization (equal), Data curation (lead), Formal analysis (lead), Investigation (lead), Methodology (equal), Validation (equal), Writing - original draft (lead);2. Materials Science and Engineering Program, Texas Materials Institute, University of Texas at Austin, Austin, TX 78712 USA |
| Abstract: | LiNiO2-based high-nickel layered oxide cathodes are regarded as promising cathode materials for high-energy-density automotive lithium batteries. Most of the attention thus far has been paid towards addressing their surface and structural instability issues brought by the increase of Ni content (>90 %) with an aim to enhance the cycle stability. However, the poor safety performance remains an intractable problem for their commercialization in the market, yet it has not received appropriate attention. In this review, we focus on the gas generation and thermal degradation behaviors of high-Ni cathodes, which are critical factors in determining their overall safety performance. A comprehensive overview of the mechanisms of outgassing and thermal runaway reactions is presented and analyzed from a chemistry perspective. Finally, we discuss the challenges and the insights into developing robust, safe high-Ni cathodes. |
