A 2.7 V Aqueous Supercapacitor Using a Microemulsion Electrolyte**
Fraser R. Hughson, Rohan Borah, Thomas Nann
Abstract
Abstract The use of aqueous electrolytes in energy storage devices is traditionally limited by the voltage stability window of water at 1.23 V. Here, we present the use of a microemulsion based electrolyte which, although mostly water by mass, has a voltage stability window of up to 5 V. This allows the cost and safety benefits of aqueous electrolytes to finally be realised in high voltage systems. Supercapacitors constructed using this electrolyte were able to achieve and maintain a capacitance of ∼40 Fg −1 and an energy density of ∼40 Wh kg −1 with a Coulombic efficiency of 99 % for over 10,000 cycles on activated carbon.
Topics & Concepts
SupercapacitorElectrolyteMicroemulsionCapacitanceAqueous solutionFaraday efficiencyMaterials scienceEnergy storageChemical engineeringVoltageChemistryElectrodeElectrical engineeringPulmonary surfactantPhysicsOrganic chemistryPower (physics)EngineeringPhysical chemistryQuantum mechanicsSupercapacitor Materials and FabricationAdvanced battery technologies researchAdvanced Battery Materials and Technologies