Efficient Lithium Growth Control from Ordered Nitrogen-Chelated Lithium-Ion for High Performance Lithium Metal Batteries.

Lithium (Li) metal has attracted significant attention as next-generation anode material owing to its high theoretical specific capacity and low potential. For enabling the practical application of Li-metal as an anode according to energy demands, suppressing dendrite growth by controlling the Li-ion (Li+) is crucial. In this study, metal-organic frameworks comprising bipyridinic nitrogen linker (M-bpyN) are proposed as 3-dimensional (3D) Li guiding matrix. The proposed approach creates ordered electronegative functional sites that enable the preoccupied Li+ in the ordered bipyridine sites to produce isotropic Li growth. The Li guiding matrix containing 3D ordered bipyridinic N sites introduces preoccupied Li+ sites that attract the Li growth direction, thereby suppressing the dendrite growth during the electrodeposition of Li. After applying the M-bpyN layers, stable lifespan of up to 900 cycles in the Li|M-bpyN|Cu cell and over 1500 h of operation in the Li|M-bpyN|Li symmetric cell is achieved. Moreover, the Li|M-bpyN|LiFePO4 configuration shows a long cycle retention of 350 cycles at 0.5 C. These results indicate that an M-bpyN Li guiding matrix, which enables a uniform Li+ flux by 3D ordered Li+-chelating sites, serve as a suitable host for Li+ and enhance the performance of Li-metal electrodes.