Modeling and Characterization of the Mechanoelectric Response of Ionic Polymer Metal Composite (IPMC) Energy Harvesters

Abstract

Electroactive Polymers (EAPs) have gained momentum in the past few years. An especially promising material, Ionic Polymer-Metal Composite (IPMC), was the subject of the reported research. IPMCs are capable of electromechanical and mechanoelectrical transduction (i.e conversion of energy from one form to another) on application of electric field and mechanical deformation, respectively. There are three key aspects of the research reported in this dissertation: develop a framework on the mechanoelectric model, evaluate the capability of IPMC as energy harvester in natural bender configuration and assess the feasibility of non-conventional configurations including disc shaped IPMC for energy harvesting applications. First of all, a framework on mechanoelectric model based on electrostatic effect and ion transport inside the membrane was developed. The model gives an insight into the mechanoelectric principle in IPMC, along with the role played by different material parameters like Young's modulus, cluster dimension, permittivity and diffusivity. Secondly, IPMC was analyzed for energy harvesting applications. The research demonstrates applicability of IPMC as energy harvester in lower frequency regions (<50 Hz) with an average efficiency of around 2% or less. Instantaneous power output from a 10 mm (width) x 50mm (length) x 0.2mm (thickness) was measured to be around 4 microW. The effect of different parameters in mechanical domain (stiffness and scalability) and electrical domain (electrode property like resistance and capacitance) was studied, both experimentally and through a formulated Grey-box model. Lastly, non-traditional configurations were tested for energy harvesting applications.