Investigation of Peo-Polymer Blend Electrolytes for Electrochemical Capacitors
Thesis
Recently, there has been a drift of attention towards gel polymer based electrolytes owing to the fact that they are cheap and can achieve an extended potential window for improved energy density in s upercapacitor devices when compared to aqueous electrolytes. Thus in this regard, the electrochemical characterization of s ymmetric s upercapacitor devices based on different polyethylene oxide (PEO) based gel electrolytes was studied. The gel polymer electrolyte is based on methanol s olvent, polyethylene oxide (PEO), lithium perchlorate (LiClO 4 ) and ionic liquid (IL), tetraethylammonium tetrafluoroborate (TEABF 4 ). Polymer electrolytes with different compositions were prepared by varying the weight percentage of each of the constituents. The EDLC device made with the electrolyte composition of PEO: 10 wt. % LiClO 4 + 20 wt. % IL showed a maximum operating voltage window of 2.3 V. A peak capacitance of 54.9 Fg -1 , energy and power density of 23.2 kWh g -1 and 10.8 kW/g were recorded. The enhanced performance were due to the improved conductivity of the electrolytes, which is favourable for fast ion transport.