Modulating Lithium Nucleation Behavior through Ultrathin Interfacial Layer for Superior Lithium Metal Batteries

Lithium metal batteries are considered as a “holy grail” of energy storage due to their high energy densities and potential applications in portable electronic devices and electric vehicles. Nevertheless, nonuniform lithium plating poses a series of problems such as dendrite growth and poor cyclability of lithium metal anodes, impeding the development of practical lithium metal batteries. Herein, an ultrathin LiC6 layer is developed to form a lithiophilic interfacial layer on the Li electrode surface by a facile pencil-drawing approach, which is used for modulating Li nucleation and growth behaviors in lithium metal batteries. The ultrathin modification layer significantly homogenizes the nucleation uniformity and dramatically suppresses the dendrite growth on the lithium metal anode. Consequently, the cycling lifespan of LiC6-modified lithium metal anode is significantly improved from 500 to 3000 h in Li||Li symmetric cells. Moreover, the LiFePO4||Li full cell is demonstrated to offer an excellent cycling stability by using the LiC6-modified lithium metal anode. This work points out a facile and effective strategy to modify electrode interfaces for developing stable lithium metal batteries.