Tailoring oxygen redox reactions in ionic liquid based Li/O2 batteries by mean of the Li+ dopant concentration
| Autor: | Alvaro Yamil Tesio, Dino Tonti, Laura Cecchetto, Marc Guardiola Espinasa, Mara Olivares-Marín, Fausto Croce |
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| Přispěvatelé: | European Commission, Ministerio de Economía, Industria y Competitividad (España) |
| Rok vydání: | 2017 |
| Předmět: |
Battery (electricity)
Inorganic chemistry Energy Engineering and Power Technology 02 engineering and technology Electrolyte 010402 general chemistry Electrochemistry 01 natural sciences 7. Clean energy Redox chemistry.chemical_compound PYR14TFSI LI+ CONCENTRATION IONIC LIQUID Dopant Renewable Energy Sustainability and the Environment Precipitation (chemistry) Chemistry Otras Ciencias Químicas Ciencias Químicas 021001 nanoscience & nanotechnology Alkali metal 0104 chemical sciences Fuel Technology Ionic liquid LITHIUM OXYGEN BATTERY 0210 nano-technology CIENCIAS NATURALES Y EXACTAS |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| Popis: | Ionic liquids’ (ILs) reusability, non-volatility and non-corrosiveness, as well as their ease of isolation and a large electrochemical stability window make them an interesting choice as environment-friendly electrolyte for metal/air batteries. ILs have been described as designer solvents as their properties and behaviour can be adjusted to suit an individual reaction need. In the framework of this study we applied a conceptually similar designer approach and show that a simple parameter as the concentration of a Li+ dopant dramatically affects the reactions yields of Li/O2 based energy storage devices. We studied the effect of Li+ concentration from 0.1 to 1 M in a LiTFSI:PYR14TFSI ionic liquid electrolyte on the kinetics of the oxygen reduction reaction (ORR) and on the formation rate of different Li-O species at two different temperatures, finding that discharge capacity, rates and product distribution change in a non-linear way. At 60 °C highest rates and up to one order of magnitude larger capacities were observed at intermediate LiTFSI concentrations, implying a complete mechanism switch from surface to volume phase mediation for Li2O2 precipitation. At room temperature the same evolution was observed, even if in this case the surface mediation remained predominant at all concentrations. These results suggest the possibility to optimise the ionic liquid based Li/O2 battery performances in terms of discharge capacity and lithium use, by playing on temperature and alkali cation concentration. Work funded by the European Commission in the Seventh Framework Programme FP7-2010-GC-ELECTROCHEMICAL STORAGE, under contract no. 265971 “Lithium-Air Batteries with split Oxygen Harvesting and Redox processes” (LABOHR), with contribution from the Spanish Ministry of Economy, Industry and Competitiveness, through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV- 2015-0496). M.O. acknowledges CSIC for a JAE-DOC research contract cofunded by the European Social Fund. A.Y.T. acknowledges research postdoctoral grant from CONICET in particular to the program "Estadías Breves en el Exterior para Becarios Postdoctorales”. We thank fruitful discussions on ionic liquids with Dr. Gianni Appetecchi, and on ionic liquid-based Li/O2 batteries with Prof. John Owen, and all LABOHR partners. |
| Databáze: | OpenAIRE |
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