Investigation of Device Dimensions on Electric Double Layer Microsupercapacitor Performance and Operating Mechanism

Abstract

Electric Double Layer Capacitor (EDLC) holds the highest share of commercial supercapacitor market. However, it has been proven that current Helmholtz, Gouy-Chapman and Stern models do not provide comprehensive explanation for energy storage mechanism in EDLC. In this work the effects of interdigitated EDLC design on capacitance of flexible laser scribed interdigitated microsupercapacitor (LSG-MSC) are studied. Three design parameters are tested, (1) current collector-electrode interaction, (2) electrode aperture, and (3) distance between parallel electrodes. Noticeable change was observed in the total capacitance upon change in LSG-MSC design which was analyzed in detail using cyclic voltammetry, electrochemical impedance spectroscopy and electrostatic simulation using COMSOL Multiphysics. It was found that in addition to electric double layer capacitance, an electric field was generated between electrodes and between electrode and current collector which led to small electrostatic capacitance between them. This electric field was also found to cause disturbance in double layer formation at the electrode thus causing change in the overall capacitance as the design parameters were varied.

Dynamic Effect of Overscreening on Electrochemical and Thermal Properties of EDLC Electrodes during Charging/Discharging Cycles

“…Note that the EDL formation dominated regime has been investigated thoroughly. [41][42][43] Thus, this study focused on the interpretation of overscreening dominated regime. Figure 7(b) shows the diffuse layer capacitance as a function of the reciprocal of the counter-ion diameter for the co-ion diameter of 0.45 nm at t ⋆ = 0.1.…”

One-dimensional physical model for complementary electrochromic device

“…Here, d Stern,i is the Stern layer length of WO 3 and NiO interface which can be calculated by [20] ( )…”

Bimetal Metal–Organic Framework-Derived Ni–Mn@Carbon/Reduced Graphene Oxide as a Cathode for an Asymmetric Supercapacitor with High Energy Density

“…Typically, supercapacitors can be classified into two main types based on their charge and discharge mechanisms: double-layered capacitors (DLCs) and faradaic (or pseudo-) capacitors. , DLCs store energy through the electrostatic absorption of electrons on the interfaces of electrode materials and electrolytes, ,− normally fabricated with carbon as the electrode materials including graphene, active carbon, and carbon nanotubes, and have merits of high durability and power density ascribed to the intrinsic properties of superb stability and the electronic conductivity of carbon. − The faradaic supercapacitors, on the contrary, generating capacitance through highly reversible redox reactions and/or pseudoprocesses between the valences of the electrode materials, , consist of transition-metal oxides or/and hydroxides as the electrodes, such as Ni, Co, Fe, V, and Mn. ,− The induced faradaic capacitance is typically several orders of magnitude higher than the double-layered capacitance. , However, the lower durability and stability as the common flows of the transition-metal oxide hinder the practical application of the faradaic supercapacitors for the gradual depletion of ions of the transition-metal electrodes during the long-life charge and discharge cycling. , …”