Executive Summary : | As a result of high energy demands of the electricity from the society and limited availability of coal/fossil fuels, the storage of energy in high power devices (such as electrochemical double layer capacitors (EDLCs), re-chargeable batteries, dye-sensitized solar cells, fuel cells, etc) is one of the most reliable approaches to solve the energy problem. In these devices, EDLCs are high power/ energy devices having two main components i.e. electrolytes and electrodes (high electron conducting with high porosity). For high power EDLCs, electrolyte should be high ionic conductivity (density of charge carriers should be high), high mechanical flexibility (for proper electrode electrolyte interface), low cost, ease of fabrication, light weight, eco-friendly, etc. EDLCs were received much attention in recent years but optimization of power density, energy density, faradic capacity and durability are still challenges for the researchers/scientists and technologists. A typical EDLC consists of a two identical composite material based porous electrodes (anode and cathode), separator and electrolyte. In order to solve these issues related to power density, specific capacitance, durability, high cyclebility electrolyte should be high ionic conducting, good flexibility and electrode should have the high porosity (accumulation of free ions near the electrodes is increased) and high electronic conductivity. The presence of ionic liquid/alkali metal salts in the plasticized bio-polymer matrix may provide high ions near the electrode-electrolyte interface hence improved above said desired properties of the EDLCs. EDLCs based on conventional electrolytes suffers from low power/energy density, solvent evaporation, corrosion, etc. which reduces its durability and create a problem in its large scale manufacturing. Recently, several approaches have been made to solve these problems by using solid electrolytes, gel electrolytes, ionic liquids and polymer electrolytes. In the present proposal, the high Ionic liquid (IL) loaded bio-polymer nano-composite electrolyte based on CMC/or CS-NaI-SiO₂/TiO₂-PC+EC will play a crucial role to enhanced desired properties of EDLCs like power density and durability. In the presence of IL, NaI (salt with low lattice energy) and SiO2 nano particles, amine and hydroxyl groups on the glucosamine unit of polyschacarides (CS/CMC) can provide the large number of free ions and hence enhanced the power density of the cell. These systems are expected to show high ionic conductivity at room temperature with good thermal and chemical stability. Hence, the proposed conducting material will be very useful for the fabrication of EDLCs. It will be also useful for industries as well as domestics and other electrochemical device applications such as batteries, DSSCs, actuators, electro-chromic display devices, etc. |