Non‐Carbon‐Dominated Catalyst Architecture Enables Double‐High‐Energy‐Density Lithium–Sulfur Batteries
Ru Xiao, Tong Yu, Shan Yang, Xiaoyin Zhang, Tianzhao Hu, Ruogu Xu, Zhuoyan Qu, Guangjian Hu, Zhenhua Sun, Feng Li
Abstract
Abstract The commonly used “catalyst on carbon” architecture as a sulfur host is difficult to jointly achieve high gravimetric and volumetric energy densities for lithium–sulfur (Li–S) batteries due to the contradiction between low tap density/poor catalytic activity of carbon and the easy agglomeration of metal‐based compounds without carbon. Here, a non‐carbon‐dominated catalytic architecture using macroporous nickel/cobalt phosphide (NiCoP) is reported as the sulfur host for Li–S batteries. The macroporous framework, which accommodates a large amount of sulfur, can accelerate the electrochemical reaction kinetics by accelerated e − transport, Li + diffusion, and superior adsorption and catalytic activity of inherent Ni 2 P/CoP heterostructures. The high tap density (0.45 g cm −3 ) and mechanically hard features contribute to the excellent structural and physicochemical stability of the NiCoP@S electrode after the pressing and rolling process. These features enable the Li–S coin cell to exhibit excellent electrochemical performance under conditions of high sulfur loading (10.2 mg cm −2 ) and lean electrolyte (electrolyte/sulfur of 2 µL mg −1 ). Inspiringly, the assembled pouch cell can simultaneously deliver a gravimetric energy density of 345.2 Wh kg −1 and an impressive volumetric energy density of 952.7 Wh L −1 based on the entire device configuration.