Ionic liquid based gel polymer electrolyte for all quasi solid state supercapacitors and lithium-ion batteries

Abstract

The work described in the thesis has been conducted with an objective to develop Gel Polymer Electrolyte based Lithium-ion batteries and Supercapacitors. Extensive literature survey has been performed on this subject. We have gone through the history, basic working principle, properties and what could be the possible future of this technology. While reviewing the literature many research papers and scientific documents were examined in order to find the current status of research in the field of Gel Polymer based Lithium-ion batteries and also Electrochemical Double layer capacitors. Li-ion batteries have been widely used in electronic devices, electrical vehicles, and large-scale charge-storage systems due to their relatively long cycling life, high energy density, low selfdischarge. Lithium ions participate in the energy-storage process in Li-ion batteries. Generally, graphite materials having good anion intercalation properties and different alloy-type materials have been used, respectively, as cathodes and anodes. The Li metal has been also used as the anode material due to its high theoretical capacity and ability to provide for high energy density. Covalent organic frameworks (COFs) are used to enhance different properties of Li-ion Batteries and Supercapacitors. Analysis and study of energy storage materials is a promising field of research for the design of electrochemical charge storage devices such as batteries and supercapacitors. It has been reported that the output power and cycling time for batteries are low, while supercapacitors provide high power density, long cycle life, superb intrinsic safety, etc. The supercapacitors store charge electrostatically or electrochemically by charge transfer mechanisms. One of the major drawbacks of supercapacitors is their low energy density. The specific capacity plays an important role in the charge storage process that depends on the electrode materials and electrolytes. The choice of proper electrolytes is essential to design supercapacitors with high energy density. Currently, ionic liquids (ILs) have received a great attention as novel electrolytes or electrolyte components due to their high ionic conductivity, nonvolatility, nonflammability, and wide range of potential stability window. The IL incorporated gel polymer electrolytes (GPEs) are suitable alternative option to replace the liquid electrolyte. Similarly, aliphatic dinitrile, has recently received great attention as a plasticizer for lithiumion batteries and supercapacitors electrolytes due to its inexpensive cost, superior thermal stability, strong ion salvation power, high boiling point, low vapor pressure, excellent electrochemical oxidation tolerance, and specific electrochemical properties. The above advantages open the gateway for further research in the field of Li ion batteries and Supercapacitors.