Lv Ze-Chen, Wang Fan-Fan, Wang Jian-Cang, Wang Peng-Fei, Yi Ting-Feng
School of Materials Science and Engineering, Northeastern University, Shenyang 110819, PR China; Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province, School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
School of Materials Science and Engineering, Northeastern University, Shenyang 110819, PR China; Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province, School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China.
J Colloid Interface Sci. 2023 Nov;649:175-184. doi: 10.1016/j.jcis.2023.06.096. Epub 2023 Jun 18.
Lithium-rich manganese-based cathode has made a subject of intense scrutiny for scientists and application researchers due to their exceptional thermal stability, high specific capacity, high operating voltage, and cost-effectiveness. However, the inclusion of cobalt, as a crucial component in lithium-rich manganese-based cathode materials, has become a cause for concern due to its limited availability and non-renewable nature, which eventually limits the growth of the battery industry and increase costs. Considering the poor stability of cobalt-free cathode, this work proposes a coating strategy of LiF through a simple high-temperature melting method. Directly coating LiF on LiNiMnO surface is found to be an effective way to protect the cathode material, decrease metal solubility, and inhibit irreversible phase transition processes, thus leading to an improved electrochemical performance. As a result, the battery employing LiF coated LiNiMnO cathode can be stabilized over 280 cycles and maintain a capacity of 110 mAh g at 1C. What's more, the mechanisms of ion insertion/extraction behavior and ion migration process are also studied systematically. This study will open the avenue to develop a high-energy battery system with cobalt-free cathode.
富锂锰基正极由于其卓越的热稳定性、高比容量、高工作电压和成本效益，已成为科学家和应用研究人员密切关注的对象。然而，作为富锂锰基正极材料的关键成分，钴的存在因其有限的可用性和不可再生的性质而引发了关注，这最终限制了电池行业的发展并增加了成本。考虑到无钴正极的稳定性较差，这项工作通过一种简单的高温熔融方法提出了一种LiF包覆策略。发现在LiNiMnO表面直接包覆LiF是保护正极材料、降低金属溶解度和抑制不可逆相变过程的有效方法，从而导致电化学性能得到改善。结果，采用LiF包覆LiNiMnO正极的电池在1C下可稳定循环超过280次，并保持110 mAh g的容量。此外，还系统地研究了离子插入/脱出行为和离子迁移过程的机制。这项研究将为开发具有无钴正极的高能电池系统开辟道路。
