A dendrite-suppressed and utilization-improved metallic Li anode enabled by lithiophilic nano-Pb decoration on carbon cloth

Abstract

The commercialization of Li metal anodes has been long hindered by uncontrolled dendrite growth, infinite volume expansion and poor Li metal utilization. Herein, we achieve a uniform nano-Pb decoration on carbon cloth (Pb@CC) by exploiting the thermal decomposition process of lead acetate trihydrate monitored by in situ Raman spectroscopy. 3D hosted Li anodes are fabricated via a record-fast infusion (1.0 s) of accurate weight-controlled molten Li into the highly lithiophilic Pb@CC host at a considerably low temperature of 250 °C. At an optimal Li loading of 10 mg, the Pb nanoparticles guide the uniform distribution of Li sites over the robust yet porous electron-conducting carbon network, which not only directs and confines Li nucleation and growth, but accommodates volume changes during repeated Li stripping/plating processes. The resulting Li electrodes afford an ultralong cycle life of 4648 h at low overpotentials of <50 mV under 1 mA cm⁻²/1 mA h cm⁻² symmetric-cell cycling, which is among the best records ever reported in the literature. The corresponding LiFePO₄ and LiNi_0.8Co_0.1Mn_0.1O₂ full cells deliver significantly higher cycling and rate performances than those with Li foils. Furthermore, the effect of Li utilization is explored in Li‖LiFePO₄ full cells, with the best cyclability achieved at a low N/P ratio of 63.28. The present findings stretch the practical feasibility of wetting-assisted molten Li infusion in mitigating dendrite growth and improving Li utilization towards long-cycling high-energy-density Li metal batteries.