Lignin derived hierarchical porous carbon with extremely suppressed polyselenide shuttling for high-capacity and long-cycle-life lithium–selenium batteries

Abstract

A low-cost scalable strategy is developed to fabricate lignin derived hierarchical porous carbon as a high-loading Se host. When combined with carbonate-based electrolyte, the high-capacity and long-term cycling Li–Se batteries were obtained. Lithium–selenium (Li–Se) batteries have attracted considerable attentions for next-generation energy storage systems owing to high volumetric capacity of 3265 mAh cm −3 and excellent electronic conductivity (~10 −5 S cm −1 ) of selenium. However, the shuttling effect and capacity fading prevent their wide applications. Herein we report a low-cost strategy for scalable fabrication of lignin derived hierarchical porous carbon (LHPC) as a new high-loading Se host for high-capacity and long-term cycling Li–Se batteries in carbonate electrolyte. The resulting LHPC exhibits three-dimensional (3D) hierarchically porous structure, high specific surface area of 1696 m 2 g −1 , and hetero-atom doping (O, S), which can effectively confine the Se particles into the micropores, and meanwhile, offer effective chemical binding sites for selenides from hetero-atoms (O, S). As a result, our Li–Se batteries based on Se@LHPC demonstrate high capacity of 450 mAh g −1 at 0.5 C after 500 cycles, with a low capacity fading rate of only 0.027%. The theoretical simulation confirmed the strong affinity of selenides on the O and S sites of LHPC effectively mitigating the Se losing. Therefore, our strategy of using lignin as the low-cost precursor of hierarchically porous carbon for high-loading Se host offers new opportunities for high-capacity and long-life Li–Se batteries.