Computational Modeling of Implantable Power Source: Miniature Enzymatic Biofuel Cell

Abstract

Steady state response of two-dimensional (2-D) model of enzymatic biofuel cell (EBFC) with three dimensional (3-D) highly dense micro arrayed electrodes has been simulated in order to analyze glucose diffusion phenomenon around electrodes; to inspect potential variation throughout electrodes; to optimize the dimensions of electrodes to augment output potential; and to analyze electric field, current density and resistive heating distribution around electrodes-substrate interfaces. In addition to these, different geometries of electrodes have also been inspected with regards to current density and resistive heating effects at electrode-electrolyte interfaces. In transient response case, we developed simulation model by integrating Fick’s diffusion law, Nernst Potential equation and Navier Stokes equation to find out best orientation of EBFC chip upon implantation in blood artery.

Maximum output potential from the electrodes is achieved when the distance between any two electrodes are kept half of their height. Non uniform potential distribution creates non uniform electric field distribution and excessive localized heating around electrodes. Current density and resistive heating study for cylindrical, cone, curved cone and tapered electrodes suggests that the curved cone electrodes give 1000 times less resistive heating as well as it gives more uniform current density distribution around electrodes, which improves the longevity of electrodes array structure.