Electroactive Polymeric Materials for Supercapacitors
Abstract
Abstract Supercapacitors (SCs) are one of the important components in the Navy s need for energy harvesting, storage, transmission, and utilization. From power ride through systems to advanced electronic devices, large and small SCs provide an opportunity to store electrical charge and supply it at rates faster than seen in rechargeable batteries, and magnitudes higher than seen with dielectric capacitors. We propose to address the three main units needed to be co-developed and optimized in order to yield supercapacitors of the highest power and energy densities with the long term stabilities required for application. These include conducting substrates/current collectors, electrolytes with high ionic conductivity, and active materials as electroactive conducting polymers (EAPs) and composites based on EAPs. In this program we propose to take advantage of a major benefit of conjugated electroactive polymers—their ability to be room temperature processed (via solution processing or electrochemical polymerization) onto substrates of various shapes and sizes. We have a new family of solution processable polymers incorporating EDOT and ProDOT units that are electroactive over a broad voltage range which can be processed from organic solvents using a variety of methods such as dip-coating, blade-coating, spray-coating, and slot-die coating. In addition, we have designed co-polymers whose solubility and electrolyte compatibility can be tuned via chemical defunctionalization to render them both water-soluble and also solvent resistant. We now aim to develop these further using several approaches. The first is by incorporating PheDOT units as this is expected to increase the charging currents and as a result the energy density. The second approach is to incorporate more EDOT units into these co-polymers to further increase the voltage window and in that way increase the energy density. A third approach we propose is to functionalize the ProDOT units with cross-linkable side chains to be able to create porous films with improved polymerelectrolyte interactions. All of these co-polymers will then be evaluated on high surface area, earth-abundant substrates, such as carbon nanotube fabrics and nanocellulose based substrates. Finally we propose to design ‘mixed-valent’ type polymers with redox active transition metal centers to expand into Type III and Type IV devices. We believe that this approach will result in polymers with highly delocalized lowest unoccupied molecular orbitals (LUMOs) while maintaining planarity between polymer repeat units such that there is a large amount of intra- and inter-chain charge mobility for true n-type reduction.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 03, 2016
- Source ID
- N000141612165
Entities
People
- John Reynolds
Organizations
- Georgia Tech Research Corporation
- Office of Naval Research
- United States Navy