Binary graphene-based cathode structure for high-performance lithium-sulfur batteries. (9th January 2020)

• Record Type: Journal Article
• Authors: Fang, Ruopian; Zhao, Shiyong; Chen, Ke; Wang, Da-Wei; Li, Feng
• Is Part Of: JPhys energy. Volume 2:Number 1(2020)
• Publication Date: 2020-01-09
• Subjects: graphene -- lithium-sulfur -- batteries -- high energy denisty; Power resources -- Research -- Periodicals; Power resources -- Periodicals; 333.79
• DOI: 10.1088/2515-7655/ab5997
• Languages: English
• ISSNs: 2515-7655

Abstract

Abstract: Lithium-sulfur (Li-S) batteries are highly appealing for the next-generation of energy storage because of their high energy density and low-cost features. However, the practical implementation of Li-S batteries has been hindered by fast performance degradation of the sulfur cathode, especially at a high cathode loading. Here, we propose a strategic design of binary graphene foam (BGF) as the cathode scaffold, with the incorporation of nitrogen-doped graphene and highly porous graphene. The nitrogen-doped graphene provides chemical adsorption sites for migrating polysulfides, and the highly porous graphene could increase the cathode conductivity and accelerate lithium ion transport. The freestanding foam-like cathode structure further offers a robust, interconnected, conductive framework to promote the redox reaction even at a high cathode loading. Therefore, the Li-S battery with the S/BGF electrode exhibits a high specific areal capacity over 10 mAh cm –2 and good cycling stability over 300 cycles. This approach offers insights into multifunctional electrode structure design, with targeted functions for high-performance Li-S batteries.