Characteristics of magnesium-sulfur batteries based on a sulfurized poly(acrylonitrile) composite and a fluorinated electrolyte. (20th November 2020)

• Record Type: Journal Article
• Authors: Wang, Peiwen; Kappler, Julian; Sievert, Brigitta; Häcker, Joachim; Küster, Kathrin; Starke, Ulrich; Ziegler, Felix; Buchmeiser, Michael R.
• Is Part Of: Electrochimica acta. Volume 361(2020)
• Publication Date: 2020-11-20
• Subjects: Magnesium foil -- Pressed magnesium anode -- Sulfur batteries -- SPANBackspace -- SEI formation; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.137024
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: A magnesium-sulfur (Mg-S) battery system based on a sulfurized poly(acrylonitrile) ("SPAN") composite as cathode material is presented. Using magnesium tetrakis(hexafluoroisopropyloxy) borate, Mg[B( hfip )4 ]2, as conductive salt in the electrolyte, the cycle performance of Mg-S batteries based on SPAN and different types of Mg anodes, i.e. Mg foil and pressed Mg powder, respectively, were compared. A cell composed of Mg foil and SPAN delivered a discharge capacity around 300 mAh/gsulfur at C/30 while a cell based on SPAN and pressed Mg powder delivered ca. 500 mAh/gsulfur (energy density of ca. 422 mWh/gsulfur ) at C/30 and also possessed good rate capability. The higher discharge capacities of Mg-S cells based on pressed anodes are attributed to the substantially higher specific surface area of the pressed cells. Post-mortem analysis of aged cells based on SPAN and a pressed Mg anode indicates the formation of MgF2 on both the cathode and the anode along with magnesium polysulfide species. Graphical abstract: Image, graphical abstract