A Realistic 3D Model of Mediator Supercapacitors in Micrometer Level

摘要

A 3-D microscopic model is set up for studying the roles of different components in mediator supercapacitor. In the model, mediator clusters are interfacing with active carbon, carbon fibers, and polymer electrolyte. Different conductivities, capacities, and mechanical properties were assigned to different components. Computational analyses were conducted using COMSOL Multiphysics. Hotspots appear around mediator clusters because of current concentration around them during charging/discharging. Further minimization of the mediator clusters will help mitigate this issue. Total capacitance of mediator supercapacitor increases exponentially when mediator capacitance and activated carbon capacitance reaches critical values. In addition, the mediator supercapacitor stores more charge with higher electrolyte conductivity. When applied pressure is high, stress concentrates around carbon fibers which cause the destruction of polymer electrolyte.