A New Conceptual Cathode and Separator Design Enabling High Energy Density Lithium-Sulfur Batteries

Abstract

Significant improvement of lithium ion batteries (LIBs) performances has been achieved with a rapid advance of portable electronic devices over the past quarter century. With a growing demand for high performance power sources, world-wide efforts have been devoted to the development of an alternative battery system to replace current LIBs which face performance limitation in terms of capacity and energy density. Recently, lithium-sulfur (Li-S) batteries have received an unprecedented attention owing to their great potentials such as a large theoretical capacity of sulfur, low toxicity and low cost. As cutting-edge nanotechnologies (e.g., C-S composite concept, mesoporous interlayer) have been employed to Li-S batteries, their performances have been dramatically improved for the past two decades. Despite such remarkable progress, there have remained many issues (i.e., limited cycling performance and low rate properties) which should be addressed for successful commercialization of Li-S batteries. In addition, most approaches to solve those problems need so complex and expensive processes which are so hard to implement them to practical mass production. Herein, we report a facile and cost-effective approach for the development of high-performance Li-S batteries. Through combining a functional separator to a high-sulfur-loading cathode, which can mitigate the active material loss and confine polysulfide ions within a specific space ensuring a long cycle life, high-performance Li-S batteries are fabricated and their characteristic features are intensively investigated.