Invited Presentation: Air Batteries with Ionic Liquid Electrolytes: The Abile Project

Abstract

Electrification has been a major focus of BMW and large efforts have been initiated in order to investigate technologies of high potential to be integrated in future electric vehicles. Metal-air and particularly lithium-air batteries [1] are one of the possible solutions that may substantially enhance the electric drive range. The main challenges in Li-air batteries are related to the stability of the electrolyte and safety of the negative electrode. BMW, together with three scientific teams initiated a project focusing on the use of ionic liquids and alternative anodes as potential components for Li-air batteries.Due to their excellent electrochemical and chemical properties, onium-based ionic liquids [2] were chosen as the first candidates. The presentation will describe the electrochemical behaviour of a Li-air cell comprising such ionic liquid-based electrolytes. The results prove the concept that the chosen ionic liquid may assure the proper lithium-oxygen cell operation and electrochemical stability during cycling.In this presentation work towards system safety improvement will be also shown [3]. In this field, alternatives to the lithium metal anode were investigated. The latter include: i) tin-carbon composite, ii) carbon-coated Zn1-xFexO [4], iii) SiOx-carbon and SiOx-silicon materials. Electrochemical tests have shown reversible behaviour of all materials both in conventional organic electrolytes as well as in electrolytes based on ionic liquids.