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Lithium (Li) metal anodes (LMAs) are promising anode candidates for realizing high-energy-density batteries. However, the formation of unstable solid electrolyte interphase (SEI) layers on Li metal is harmful for stable Li cycling; hence, enhancing the physical/chemical properties of SEI layers is important for stabilizing LMAs. Herein, thiourea (TU, CH 4 N 2 S) is introduced as a new catalyzing agent for LiNO 3 reduction to form robust inorganic-rich SEI layers containing abundant Li 3 N. Due to the unique molecular structure of TU, the TU molecules adsorb on the Cu electrode by forming CuS bond and simultaneously form hydrogen bonding with other hydrogen bonds accepting species such as NO 3 - and TFSI - through its NH bonds, leading to their catalyzed reduction and hence the formation of inorganic-rich SEI layer with abundant Li 3 N, LiF, and Li 2 S/Li 2 S 2 . Particularly, this TU-modified SEI layer shows a lower film resistance and better uniformity compared to the electrochemically and naturally formed SEI layers, enabling planar Li growth without any other material treatments and hence improving the cyclic stability in Li/Cu half-cells and Li@Cu/LiFePO 4  full-cells., (© 2023 Wiley-VCH GmbH.)

An artificial lithium-nitrate (LiNO 3 )-rich layer (LN-RL) is developed to address dendritic lithium (Li) growth by a fusing-infusing strategy, in which LiNO 3 is loaded into stainless steel mesh and a Li-metal anode (LN-RL@Li) is obtained by casting this LN-RL onto Li foil. The LN-RL enables fast Li deposition kinetics in carbonates and endows LN-RL@Li with excellent cycleability. The underneath mechanism on the contribution of LN-RL is uncovered by detailed characterizations combining with theoretical simulations. The LN-RL promotes the desolvation and capacitive adsorption of Li ions and induces in-plane Li growth along the edges of preplated Li with planar morphology. The improved cycleability of LN-RL(@Li) is demonstrated by LiǁCu cell that presents a coulombic efficiency of 97.2% after 280 cycles and LiǁLi cell that proceeds over 1000 h at 0.5 mA cm -2 in carbonates. Additionally, the LiǁLiFePO 4 cell shows a capacity retention of 58% after 400 cycles at 1 C (1 C = 170 mA g -1 ), compared to the 35% after 180 cycles for the control. This work presents not only a promising strategy for practical applications of Li-metal batteries, but also a new understanding on the role of nitrate in Li plating/stripping kinetics., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)