Characterization of Polymerized Sulfur Cathodes upon Cycling
Recently, researchers have developed a copolymer with a very high sulfur content via a process termed inverse vulcanization.1 The sulfur-containing polymer is inexpensive to produce, and full Li-S cells utilizing this copolymer in the cathode achieve capacities of 635 mAhr/g after 500 cycles at a rate of C/10.2
This talk will focus on results of characterization studies to determine the morphology and composition of the sulfur copolymer cathode and electrolyte solution during the cycling process. Microscopy studies show that the sulfur copolymer cathode maintains greater uniformity and shows less cracking upon cycling than an elemental sulfur cathode. We will also report on results of in-situ Raman and XPS studies to identify the products present in the cathode and in the electrolyte at various potentials during cycling.
1. J. Pyun et. al., Nature Chemistry, 5:518-524, 2013.
2. J. Pyun, et. al., ACS Macro Letters, 3:229-232, 2014.