An Intrinsically Non‐flammable Electrolyte for High‐Performance Potassium Batteries. (20th January 2020)

• Record Type: Journal Article
• Authors: Liu, Sailin; Mao, Jianfeng; Zhang, Qing; Wang, Zhijie; Pang, Wei Kong; Zhang, Lei; Du, Aijun; Sencadas, Vitor; Zhang, Wenchao; Guo, Zaiping
• Is Part Of: Angewandte Chemie. Volume 132:Number 9(2020)
• Page Start: 3667
• Page End: 3673
• Publication Date: 2020-01-20
• Subjects: Batterien -- Nichtflammbare Materialien -- Phosphate -- Kalium -- Lösungsmittel; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201913174
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Potassium‐ion batteries are promising for low‐cost and large‐scale energy storage applications, but the major obstacle to their application is the lack of safe and effective electrolytes. A phosphate‐based fire retardant such as triethyl phosphate is now shown to work as a single solvent with potassium bis(fluorosulfonyl)imide at 0.9 m, in contrast to previous Li and Na systems where phosphates cannot work at low concentrations. This electrolyte is optimized at 2 m, where it exhibits the advantages of low cost, low viscosity, and high conductivity, as well as the formation of a uniform and robust salt‐derived solid‐electrolyte interphase layer, leading to non‐dendritic K‐metal plating/stripping with Coulombic efficiency of 99.6 % and a highly reversible graphite anode. Abstract : Phosphatbasierte Flammschutzmittel, z. B. Triethylphosphat (TEP), erweisen sich als Lösungsmittel für Kalium‐Bis(fluorsulfonyl)imid (KFSI). Die Elektrolyte bilden eine gleichmäßige und robuste Feststoff‐Elektrolyt‐Schicht (SEI), die zu einer dendritfreien Platierung/Strippung von Kaliummetall auf einer hoch reversiblen Graphitanode mit einem Coulomb‐Wirkungsgrad von 99.6 % führt.