Synthesis of Ionic Dendrimers and Their Potential Use as Electrolytes for Lithium–Sulfur Batteries. Issue 2 (8th December 2019)

• Record Type: Journal Article
• Authors: Lebherz, Tim; Weldin, Dianne L.; Hintennach, Andreas; Buchmeiser, Michael R.
• Is Part Of: Macromolecular chemistry and physics. Volume 221:Issue 2(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-12-08
• Subjects: batteries -- dendrimers -- electrolytes -- sulfurized poly(acrylonitrile); Polymers -- Periodicals; Polymerization -- Periodicals; Synthetic products -- Periodicals; Macromolecules -- Periodicals; 547.7
• DOI: 10.1002/macp.201900436
• Languages: English
• ISSNs: 1022-1352

Abstract

Abstract: A series of ionic dendrimers is synthesized and used as conducting salt in carbonate‐based electrolytes for Li/S‐cells. The resulting electrolytes display increasing viscosity with increasing chain length of the side chains, both in the first‐ and second‐generation dendrimers. Higher conductivity is observed for the first‐generation dendrimers as compared to the second‐generation ones. While all cells show high cycle stability, the differences in dendrimer structure also influence the electrochemical behavior of the Li–S cells. Thus, discharge capacities of the corresponding Li–S cells correlate both with the viscosity and the conductivity of the electrolytes. The best electrolyte system is obtained with a first‐generation dendrimer having a short side chain, D1‐1, having the lowest viscosity and the highest conductivity, which delivers discharge capacities of 1150 mAh gsulfur −1 @ 0.5 C and 780 mAh gsulfur −1 @ 1 C. Abstract : Novel ionic dendrimers are synthesized and investigated for their potential use as conductive salts in electrolytes for Li–S cells. The electrochemistry of ionic dendrimer‐based electrolytes is mainly influenced by the length of the rest R, which leads to higher viscosities and reduced discharge capacities. The best cells reach discharge capacities of 1150 mAh gsulfur −1 @0.5 C and 780 mAh gsulfur −1 @1 C.