Carvalho Alexandra, Nair Vivek, Echeverrigaray Sergio G, Castro Neto Antonio H
Institute for Functional Intelligent Materials, National University of Singapore, 117544, Singapore.
CRADLE Singapore, Hyundai Motor Innovation Center in, 649674, Singapore.
ACS Omega. 2024 Jul 24;9(31):33912-33918. doi: 10.1021/acsomega.4c04118. eCollection 2024 Aug 6.
We have investigated the lithium capacity of the 2 phase of niobium sulfide (NbS) using density functional theory calculations and experiments. Theoretically, this material is found to allow the intercalation of a double layer of Li in between each NbS layer when in equilibrium with metal Li. The resulting specific capacity (340.8 mAh/g for the pristine material, 681.6 mAh/g for oxidized material) can reach more than double the specific capacity of graphite anodes. The presence of various defects leads to an even higher capacity with a partially reversible conversion of the material, indicating that the performance of the anodes is robust with respect to the presence of defects. Experiments in battery prototypes with NbS-based anodes find a first specific capacity of about 1,130 mAh/g, exceeding the theoretical predictions.
我们使用密度泛函理论计算和实验研究了硫化铌（NbS）两相的锂容量。从理论上讲，发现这种材料在与金属锂达到平衡时，允许在每个NbS层之间嵌入双层锂。由此产生的比容量（原始材料为340.8 mAh/g，氧化材料为681.6 mAh/g）可以达到石墨阳极比容量的两倍以上。各种缺陷的存在导致材料部分可逆转化，从而具有更高的容量，这表明阳极的性能对于缺陷的存在具有很强的耐受性。基于NbS阳极的电池原型实验发现首次比容量约为1130 mAh/g，超过了理论预测。
