Flexible and Hierarchically Structured Sulfur Composite Cathode Based on the Carbonized Textile for High-Performance Li–S Batteries

Abstract

Carbon hosts have been utilized to obtain composite cathodes with high sulfur loadings for Li-S batteries. However, the complicated synthesis process may hinder their practical applications. Their mechanical and electrochemical properties shall be further improved. Herein, a facile scalable dip-coating process is developed to synthesize a flexible composite cathode with a high sulfur loading. Via the process, a hybrid composed of carbon nanotubes, carbon black, sulfur, and titania nanoparticles is successfully conformally coated on the carbonized textile (c-textile). The formed flexible c-textile@S/TiO cathodes with sulfur loadings of 1.5 and 3.0 mg cm can deliver reversible discharge capacities of 860 and 659 mA h g at 2 C, respectively. For the latter one, it can retain 94% of the initial capacity after 400 cycles with a high Coulombic efficiency (∼96%). When its sulfur loading is further increased to 7.0 mg cm, its areal capacity reaches 5.2 mA h cm. Such excellent performance is ascribed to the synergy effect of the three-dimension conductive hierarchical pore structure and TiO additive. They can physically and chemically entrap the soluble polysulfides in the composite cathode. The as-synthesized free-standing composite electrode is of low cost and a high areal capacity, making it suitable for flexible energy storage applications based on Li-S batteries.

Smart Textile‐Integrated Microelectronic Systems for Wearable Applications

“…They store energy by converting the electrical energy into chemical form. Li‐based batteries, including Li–ion, Li–S and Li–air batteries, etc., have been intensely investigated in recent years. In addition, some other ones, such as Al–air, Zn–air, Si–O 2 , Ni–Zn, and Zn–MnO 2 batteries were investigated recently.…”

“…In addition, this battery exhibited superior electrochemical performances even under stringent bending and twisting conditions (Figure g). Mei et al fabricated a hierarchical sulfur composite cathode based on carbonized textile for Li–S battery . By using a facile scalable dip‐coating method, the authors successfully coated carbon‐based materials, sulfur and titania nanoparticles onto the carbonized textile substrate.…”

Cathode Materials for Rechargeable Lithium‐Sulfur Batteries: Current Progress and Future Prospects

“…The strong LiÀ O/SNÀ S/OÀ S bond and tight chemical adsorption between LPS and SnO 2 reduced the shuttle effect of LSBs. Gao et al [89] proposed a scalable and straightforward dip-coating process to coat a hybrid material composed of CNTs, carbon black, sulfur, and titanium dioxide nanoparticles on a carbonized fabric (C-textile) to form flexible carbon fibers@S/TiO 2 (Figure 6f-g). Due to the synergistic effect of the 3D conductive pore structure and the TiO 2 additive, cathodes with a sulfur content of 1.5 and 3.0 mg cm À 2 provided reversible discharge capacities of 860 and 659 mAh g À 1 at 2 C, respectively.…”

“…f) Photographs of the obtained c-textile and ctextile@S/TiO 2 composite; g) SEM image of the c-textile@S/TiO 2 composite with sulfur mass loading of 3.0 mg cm À 2 . Reproduced with permission from Ref [89]…”

Micro‐Mesoporous Carbons from Cyclodextrin Nanosponges Enabling High‐Capacity Silicon Anodes and Sulfur Cathodes for Lithiated Si‐S Batteries

“…[8] To successfully operate, sulfur must be well combined with lightweight conductive additives and these are again carbons, usually with large surface area and suitable porosity to achieve fast kinetics. [24,25] Rational design of hollow structures [26] and flexible carbon supports [27] allowed to load adequate amounts of elemental sulfur and buffer the volume expansions during cycling. Indeed, for the huge demand of energy storage devices, the production of high-quality carbons through cheap and sustainable means has also become a necessity.…”