The Role of Carbon-Based Cathode Components in Li–S Batteries

Abstract

Carbon-based cathode materials play a crucial role in the development of alternative battery technologies. For lithium-sulfur batteries, carbonaceous S-hosts and carbon-sulfur copolymers have been reliably used as cathode materials to improve battery cyclability and working lifetimes. Characterizing these carbon-based materials in their as-prepared state, when fabricated into cathodes, and during electrochemical function requires the use of multiple complementary techniques probing various length scales, e.g., atomic, nanometer, micrometer. Appropriate coupling of characterization techniques and interpretation of data allows researchers to accurately establish the relationship between composition, structure, and property, which in turn facilitates rational design of complex materials. These combined strategies have provided some of the most detailed insights surrounding the role and design of carbon-based materials to date. This review covers some of the ways both conventional and emerging analytical techniques have been used by researchers to investigate carbon-based cathode materials for Li-S batteries.

Optimization of Carbon/Sulfur Composite and Application of Al-LLZO Solid Electrolyte and Highly Concentrated Electrolytes for Lithium-Sulfur Cell

“…This result is in good agreement with previous results. [16][17][18][19][20] The discharge capacities for the first, second, and third cycles were 883, 793, and 764 mA h g ¹1 , respectively, for C/S KB. Those for C/S CNF were 827, 736, and 648 mA h g ¹1 , respectively, while for C/S CNT it was 914, 808, and 697 mA h g ¹1 , respectively.…”

“…To facilitate the electrochemical reactions involving S, it is necessary to incorporate conductive materials within the S-cathode layer, thereby establishing an electronically conductive matrix. [10][11][12][13][14][15][16][17] Another important issue is the dissolution of intermediate species during the electrochemical reduction of S. It is well known that Li 2 S 8 and Li 2 S 6 tend to dissolve into non-aqueous electrolytes, which have traditionally been used in conventional Li-ion batteries. These dissolved intermediates migrated towards the Li-metal anode and reacted with the Li-metal.…”

“…[18][19][20][21][22][23][24][25] Notably, the conductivity of the cathode layer can be improved using carbon (C)-materials, such as Ketjen Black (KB), as discussed in previous research. [10][11][12][13][14][15][16][17] In this study, we examined three types of C-materials: KB, Cnanofibers (CNFs), and C-nanotubes (CNTs). We prepared three composite materials composed of C and S (C/S) to facilitate fast and reversible kinetics within the S-cathode material.…”

Recent advances in carbon-based sulfur host materials for lithium-sulfur batteries

“…Thereinto, the porous carbon shell can prevent the outward diffusion of LiPS through the physical barrier, while the larger space inside can improve the sulfur loading and relieve the volume expansion of sulfur. In addition, multistage pores are also conducive to accelerating ion transport and limiting LiPS dissolution [36] . However, due to the weak physical force between the non-polar surface of carbon and polar LiPS, the shuttle effect is hard to inhibit.…”

Electrochemical performance study of nano-Fe3O4/C modified separator for lithium-sulfur batteries

“…To address these challenges, researchers have devoted significant efforts to finding solutions. Carbonaceous materials have been widely investigated as hosts for sulfur in Li-S cells due to their ability to improve conductivity, trap soluble LiPSs, and mitigate volume changes in the sulfur cathode [11][12][13][14][15][16][17]. However, conventional carbon materials lack polarity, making it difficult to effectively immobilize polar polysulfides.…”