Defect-Modulated MOF Nanochannels for the Quasi-Solid-State Electrolyte of a Dendrite-Free Lithium Metal Battery
Jialong Jiang, Runhao Zhang, Jiachen Guo, Shiqi Zhang, Xu Min, Ziyang Liu, Ning Liu, Dapeng Cao, Jun Xu, Peng Cheng, Wei Shi
Abstract
Efficient and selective Li + transport within the nanochannel is essential for high-performance solid-state electrolytes (SSEs) in lithium metal batteries. Introducing Li + hopping sites into SSEs shows great potential for promoting Li + transport; however, it typically reduces the Li + transport nanochannel size, consequently increasing the energy barrier for Li + transport. Herein, we present a molecular defect strategy for MOFs to introduce Li + hopping sites and increase the nanochannel size simultaneously as quasi-solid-state electrolytes (QSSEs). Compared with the defect-free Li@UiO-66-based QSSE, the optimized Li@UiO-66-D2-based QSSE exhibits a remarkable 343% enhancement in Li + conductivity and improved Li + selectivity. Furthermore, the 9 cm × 6 cm Li|Li@UiO-66-D2|LFP pouch cell exhibits excellent cycling performance with high capacity retention. An in-depth mechanism study has unveiled the significant impact of both hopping sites and nanochannel size on Li + transport, emphasizing the importance of a molecular defect strategy in enhancing the overall Li + transport performance of MOF-based QSSEs.