Solid-State Hybrid Supercapacitor of PEDOT:PSS//LiFePO4 Configuration Fabricated with Gel Polymer Electrolyte
1Physics, Swami Shraddhanand College, University of Delhi, Delhi, Delhi, India
2Physics & Astrophysics, University of Delhi, Delhi, Delhi, India
*Email Address : mmanoj.ssi@gmail.com
Abstract : Hybrid BatCap, a latest generation of hybrid supercapacitor, has the possibility to overcome the energy density limitation of the symmetric supercapacitor configuration and the power density limitation in lithium-ion batteries. We report the comparative performance of symmetric pseudocapacitor PEDOT:PSS//PEDOT:PSS and hybrid BatCap PEDOT:PSS//LiFePO4 employed with polymer electrolyte (GPE) as electrolyte/separator. A free-standing, flexible film comprising of 1M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in ionic liquid 1-butyl-1-methyl pyrrolidinium bis(trifluoromethanesulfonyl)imide (BMPTFSI) immobilized in poly(vinylidene fluoride-co-hexafluoro-propylene) (PVdF-HFP) shows excellent properties such as electrochemical window of 2.9 V and high ionic conductivity of 1.38×10-3 S cm-1 at room temperature. The performance characteristics of supercapacitor have been evaluated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and galvanostatic charge/discharge techniques. The hybrid BatCap PEDOT:PSS//LiFePO4 has been found to offered better performance in terms of specific capacity (29.4 mA h g-1), specific energy (21.3 Wh kg-1) and specific power (1.2 kW kg-1) as compared to symmetric pseudocapacitor PEDOT:PSS//PEDOT:PSS.
Keywords : Hybrid BatCaps,Gel polymer electrolyte,Lithium iron phosphate,Conducting polyme