Celasun Yagmur, Colin Jean-François, Martinet Sébastien, Benayad Anass, Peralta David
CEA, LITEN, University Grenoble Alpes, F-38054 Grenoble, France.
Materials (Basel). 2022 Apr 22;15(9):3037. doi: 10.3390/ma15093037.
Lithium-rich disordered rocksalt Li2TiS3 offers large discharge capacities (>350 mAh·g−1) and can be considered a promising cathode material for high-energy lithium-ion battery applications. However, the quick fading of the specific capacity results in a poor cycle life of the system, especially when liquid electrolyte-based batteries are used. Our efforts to solve the cycling stability problem resulted in the discovery of new high-energy selenium-substituted materials (Li2TiSexS3−x), which were prepared using a wet mechanochemistry process. X-ray diffraction analysis confirmed that all compositions were obtained in cation-disordered rocksalt phase and that the lattice parameters were expanded by selenium substitution. Substituted materials delivered large reversible capacities, with smaller average potentials, and their cycling stability was superior compared to Li2TiS3 upon cycling at a rate of C/10 between 3.0−1.6 V vs. Li+/Li.
富锂无序岩盐Li2TiS3具有较大的放电容量（>350 mAh·g−1），可被视为用于高能锂离子电池应用的有前景的正极材料。然而，比容量的快速衰减导致该系统的循环寿命较差，特别是当使用基于液体电解质的电池时。我们为解决循环稳定性问题所做的努力导致发现了新的高能硒取代材料（Li2TiSexS3−x），其通过湿机械化学工艺制备。X射线衍射分析证实，所有组成均以阳离子无序岩盐相获得，并且晶格参数因硒取代而扩大。取代材料具有较大的可逆容量和较小的平均电位，并且在相对于Li+/Li为3.0−1.6 V的C/10速率下循环时，其循环稳定性优于Li2TiS3。
