First Investigations Towards the Feasibility of an Al/Br2 Battery Based on Ionic Liquids. Issue 11 (15th September 2017)

• Record Type: Journal Article
• Authors: Hog, Michael; Burgenmeister, Benedikt; Bromberger, Kolja; Schuster, Michael; Riedel, Sebastian; Krossing, Ingo
• Is Part Of: ChemElectroChem. Volume 4:Issue 11(2017)
• Page Start: 2934
• Page End: 2942
• Publication Date: 2017-09-15
• Subjects: Aluminum -- bromine -- batteries -- ionic liquids -- overpotential; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.201700700
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: We present first investigations towards the feasibility of an Al/Br2 battery based on ionic liquids (ILs). The charged battery consisted of an Al anode, a bromoaluminate IL as the anolyte, an ion‐exchange membrane, a polybromide IL as the catholyte, and an inert cathode. The open‐circuit voltage (OCV) of the battery was strongly dependent on the molar ratio of AlBr3 in the anolyte with values of 1.9 V when using a Lewis basic anolyte and 1.1 V when using a Lewis neutral anolyte. NMR studies with different organic cations in both electrolytes revealed the migration of organic cations as major charge‐balancing ions, which leads to a reduced theoretical energy density of 33 Wh L −1 (as opposed to 166 Wh L −1 for an anion mechanism). The battery could be discharged with high discharge resistance values of up to 3 kΩ cm 2, and preliminary charging attempts revealed high overpotentials. Hitherto, an Al/Br2 cell with a Lewis basic anolyte could be used as primary battery with an OCV of 1.9 V. Abstract : Al/Br2 battery : First investigations towards the feasibility of an Al/Br2 battery (see picture) based on bromoaluminate and polybromide ionic liquids are presented. The battery exhibits an open‐circuit voltage of 1.1 V and a theoretical energy density of 33 Wh L −1 based on the migration of cations, which could be determined through NMR studies. The battery can be discharged with high resistance values and preliminary charging attempts revealed high overpotentials.