Journalartikel

Jahr der Veröffentlichung: 2016

Seiten: 7756-7765

Zeitschrift: ACS Applied Materials & Interfaces

Bandnummer: 8

Heftnummer: 12

ISSN: 1944-8244

eISSN: 1944-8252

DOI Link: https://doi.org/10.1021/acsami.5b10979

Verlag: American Chemical Society

Abstract: 
Because of their exceptionally high specific energy, aprotic lithium oxygen (Li-O-2) batteries are considered as potential future energy stores. Their practical application is, however, still hindered by the high charging overvoltages and detrimental side reactions. Recently, the use of redox mediators dissolved in the electrolyte emerged as a promising tool to enable charging at moderate voltages. The presented work advances this concept and distinctly improves capacity and cycling stability of Li-O-2 batteries by combining high redox mediator concentrations with a solid electrolyte (SE). The use of high redox mediator concentrations significantly increases the discharge capacity by including the oxidation and reduction of the redox mediator into charge cycling. Highly efficient cycling is achieved by protecting the lithium anode with a solid electrolyte, which completely inhibits unfavored deactivation of oxidized species at the anode. Surprisingly, the SE also suppresses detrimental side reactions at the carbon electrode to a large extent and enables stable charging completely below 4.0 V over a prolonged period. It is demonstrated that anode and cathode communicate deleteriously via the liquid electrolyte, which induces degradation reactions at the carbon electrode. The separation of cathode and anode with a SE is therefore considered as a key step toward stable Li-O-2 batteries, in conjunction with a concentrated redox mediator electrolyte.

Harvard-Zitierstil: Bergner, B., Busche, M., Pinedo, R., Berkes, B., Schröder, D. and Janek, J. (2016) How To Improve Capacity and Cycling Stability for Next Generation Li-O-2 Batteries: Approach with a Solid Electrolyte and Elevated Redox Mediator Concentrations, ACS Applied Materials & Interfaces, 8(12), pp. 7756-7765. https://doi.org/10.1021/acsami.5b10979

APA-Zitierstil: Bergner, B., Busche, M., Pinedo, R., Berkes, B., Schröder, D., & Janek, J. (2016). How To Improve Capacity and Cycling Stability for Next Generation Li-O-2 Batteries: Approach with a Solid Electrolyte and Elevated Redox Mediator Concentrations. ACS Applied Materials & Interfaces. 8(12), 7756-7765. https://doi.org/10.1021/acsami.5b10979