Lightweight Materials for High Energy Density Lithium–Sulfur Batteries

The recent progress with regard to the application of lightweight materials in Li-S battery systems is systematically reviewed. The application of lightweight materials can reduce the mass ratio of inactive materials, provide abundant conductive paths, accelerate the reaction rate of sulfur, and so on. On this basis, the significance of the application of lightweight materials to improve the energy density of batteries is analyzed in detail.

Abstract

At present, electronic devices such as electric vehicles and mobile phones have increasing requirements for battery energy density. Lithium–sulfur batteries (LSBs) have a high theoretical energy density and are considered a potential choice for realizing the next generation of high energy density (2600 W h kg⁻¹) batteries. However, the actual energy density of LSBs is much lower than the theoretical energy density due to the poor conductivity of sulfur, serious LiPSs shuttle, low sulfur utilization, and so on. Many lightweight materials are characterized by high surface area and designability. The reasonable design of lightweight materials to modify LSBs can reduce the proportion of inactive substances by optimizing electrochemical performance, which is crucial to improving the energy density of LSBs. However, few reviews discuss the effect of lightweight materials on the energy density of LSBs from the perspective of the whole battery system. Herein, the application of lightweight materials in LSBs from six aspects: liquid electrolyte, solid electrolyte, cathode, anode, separator, and current collector is discussed. The significance of reasonable design and use of lightweight materials for the further improvement of the energy density of LSBs is summarized and prospected.