Surface lithiophilicity modification with triazole to realize dendrite-free lithium metal anode

A large nucleation overpotential on most metal substrates can cause uneven nucleation of Li, causing inhomo-geneous Li deposition, leading to tip effects and gradually evolve into dendrites and dead Li. Surface lith-iophilicity modification is conducive to promoting Li nucleation, thus avoid the generation of dendrites and form uniform Li deposition. Herein, 3-mercapto-1,2,4-triazole (MT) is used to modify the surface of Cu foil to form lithiophilic modification layer decorated Cu electrode (MT/Cu). Due to the lone pair of electrons on N and S in the MT molecules, Li+ can be easily absorbed, thus realizing uniform and dendrite-free deposition, and improving cycling stability. After plating/stripping cycles for asymmetric cell, an average Coulombic efficiency up to 99.76 % can be achieved. When the Li-loaded composite anode (Li/MT/Cu) is matched with LiFePO4 cathode, the full cell possesses a capacity retention rate of 98.3 % after 200 cycles at 1 C, and the Coulombic efficiency throughout the process maintains over 99 %. This method of surface lithiophilicity modification is simple and effective, which can provide new ideas for the composition and modification of Li metal anodes.