Circumferential Li metal deposition at high rates enabled by the synergistic effect of a lithiophilic and ionic conductive network

Combining Li-metal anodes with high-energy cathodes can hopefully produce high-energy-density batteries (∼500 W h kg −1 ). However, practical applications of Li-metal anodes are limited by irregular Li growth, which leads to a short cycling life and serious security risks. Herein, we report a flexible network consisting of Li 0.33 La 0.56 TiO 3 /carbon nanowires coated with an Au layer (LLTO/C@Au) to work as a Li metal host. The LLTO nanocrystals encapsulated in carbon increase the Li ion conductivity and flexibility of the network. Moreover, the lithiophilic Au layer leads to a feasible and homogeneous Li metal deposition at the surface, which further boosts the Li ion migration in the nanowires. As a result, the diffusion coefficient of the lithiophilic and ionic conductive network (LLTO/C@Au) is much higher than that of the only ionic conductive network (LLTO/C) and the only lithiophilic network (C@Au). Such synergistic effects of the lithiophilic and ionic conductive network on simultaneously optimizing the nucleation, transportation, and accumulation of Li enable circumferential Li metal plating/stripping at high rates. The LLTO/C@Au-Li symmetrical cell can run at a high rate of 20 mA cm −2 for 150 cycles with a capacity of 2 mA h cm −2 and at a rate of 2 mA cm −2 for 500 h with a large capacity of 10 mA h cm −2 . This work sheds light on the synergistic mechanism of a lithiophilic and ionic conductive network on the Li metal deposition, which offers a new perspective for designing advanced Li-metal batteries with low negative/positive ratio. LLTO/C composites form fast Li + diffusion paths. The lithiophilic Au layer coated on LLTO/C improves the surface lithiophilicity and further accelerates Li + diffusion, realizing uniform Li metal deposition at high rates.