Free Stand Lithiophilic Composite as Anode Electrode in Li Metal Batteries

Metallic lithium is demonstrated as one of the most attractive high energy density anodes for lithium batteries. However, it faces a great challenge in realizing practical applications because of uncontrollable lithium dendrite formation, dead lithium generation, capacity decay, and poor coulombic efficiency, which gives rise to internal short circuit, safety hazards and short cycle life. To address these issues, three dimensional hosts can be applied to realize uniform Li nucleation. Here we report a carbon-based 3D skeleton (SiO2/CNT/CP) with SiO2 nanoparticles anchored carbon nanotubes (CNTs) coated on carbon paper (CP) to induce uniform Li plating in lithium metal batteries. SiO2 in the skeleton supplies abundant nucleation sites which lead to enhance lithophilicity. Furthermore, the ingenious hierarchical structure promotes uniform Li plating by equalising the current density distribution. The obtained SiO2/CNT/CP electrodes exhibit an excellent Coulombic efficiency of 99.99% at 1 mA cm-2 after 580 cycles while a symmetric cell shows a low voltage hysteresis of 40 mV without notable fluctuation for over 1250 h.