Controllably regulating ion transport in lithium metal batteries via pore effect of metal-organic framework-based separators
作者：HongyanYao，LitingYan*，Jianxing Shen*，Tailin Wang，Pan Chen，Xiao tong Cong，Shuo Zhang，Huimin Jiang，Xue
關鍵字：Lithium Metal battery；Metal-organic framework；Separator； Ion transport；Pore effect
論文來源：期刊
具體來源：Applied Surface Science，2022，589, 152885
發表時間：2022年
Lithium Metal batteries (LMBs) are considered as excellent energy storage systems due to their ultra-high energy density. However, the growth of Li dendrites resulting from irregular transport of ions during cycling seriously limits their further development and application. Therefore, it is urgent and important to regulate the ion transport and inhibit the formation of Li dendrites. In this paper, a Metal-Organic Framework (MOF, UiO-66-NH2) coating is proposed to functionalize a conventional commercial polypropylene (PP) separator to regulate ion transport in liquid electrolytes. Grafted -NH2 groups in the MOF act by hydrogen bonding to immobilize anions in the electrolyte, which in turn facilitates cation transport. Compared with the PP separator, the Li ion transfer number (t(Li)(+)) of PP-UiO-66-NH2 (PUN) separator increases from 0.45 to 0.68. The Li/Li symmetric cell with PUN separator has an ultra-stable Li plating/stripping cycle of up to 400 h, during which time no lithium dendrite growth. In addition, the LiFePO4/Li and LiNi0.8Co0.1Mn0.1O2/Li batteries with the PUN separator exhibit excellent performance. The new strategy is controllable and universal and can be used for the preparation of various separators with outstanding performances by accurately tuning of MOF structure.