Rational design and superfast production of biomimetic, calendering-compatible, catalytic, sulfur-rich secondary particles for advanced lithium-sulfur batteries

Abstract

Scalable fabrication of thick sulfur electrodes with high-energy-density and good calendering-compatibility is a prerequisite for the practical success of lithium-sulfur batteries. However, this task turns out extremely challenging due to the lack of scalable production of rationally designed sulfur-rich particles, as well as fundamental understanding of the main issues of thick electrodes. Here, we develop a hail-inspired sulfur nanostorm (HSN) technology to efficiently produce calendering-compatible sulfur-rich secondary particles with customizable composition and material functions. To dig out the fundamental links between sulfur-rich particles properties and their electrochemical performance, an electro-mechanical method is proposed to evaluate the sulfur-rich particles properties (calendering-compatibility and conductivity). Meanwhile, the role of active material calendering-compatibility in controlling its electrochemical performance is discussed by a “healthy” microenvironment model as learned from cell biology. Consequently, a high areal capacity of 12 mAh cm−2 @ 1 mA cm−2 is realized in coin-cell. Furthermore, a pouch cell with a high specific capacitance of 1294 mAh g−1 in a quasi-lean electrolyte is successfully demonstrated. In a nutshell, this study may provide guidelines for the design, fabrication and characterization of high-quality of thick sulfur cathode for Li-S batteries.