Engineering Geometric Electrodes for Electric Field‐Enhanced High‐Performance Flexible In‐Plane Micro‐Supercapacitors

Abstract

In plane micro‐supercapacitors that are miniaturized energy storage components have attracted significant attention due to their high power densities for various ubiquitous and sustainable device systems as well as their facile integration on various flexible/wearable platform. To implement the micro‐supercapacitors in various practical applications that can accompany solid state or gel electrolyte and flexible substrates, ions must be readily transported to electrodes for achieving high power densities. Herein, we show large enhancement in electrochemical properties of flexible, in‐plane micro‐supercapacitor using sharp‐edged interdigitated electrode design, which was simply fabricated through direct laser scribing method. The sharp‐edged electrodes allowed strong electric field to be induced at the corners of the electrode fingers which led to the greater accumulation of ions near the surface of electrode, significantly enhancing the energy storage performance of micro‐supercapacitors. The electric field‐enhanced in‐plane micro‐supercapacitor showed the volumetric energy density of 1.52 Wh L−1 and the excellent cyclability with capacitive retention of 95.4% after 20 000 cycles. We further showed various practicability of our sharp‐edged design in micro‐supercapacitors by showing circuit applicability, mechanical stability, and air stability. These results present an important pathway for designing electrodes in various energy storage devices.

Flexible electrochemical energy storage devices and related applications: recent progress and challenges

“…Moreover, it achieves an impressive area-ratio capacitance of 36.46 mF cm −2 within a compact thickness of only 100 μm, thereby showcasing its potential for seamless integration into wearable electronic devices. Lee et al 72 improved the process of laser engraving to design flexible SCs, wherein the electrode layer was designed with intersecting sharp edges to induce a pronounced electric field at the corners of the electrode fingers, thereby augmenting charge accumulation near the electrode surface ( Fig. 6e ).…”

Enhanced Electrical Injury Using Triangular Interdigitated Electrodes for Catheter-Based Irreversible Electroporation

“…In addition, interdigitated electrodes (IDEs) have been studied for their ability to reduce the required voltage and localize the electric fields at the desired region [13,14]. IDEs further allow the electrode distance to be closer and thinner due to simple in-plane geometry [18,19]. Most of the finger structures of IDEs reported so far have a rectangular cross-section, and most studies in this area have focused on the effects of the finger's width, length, and period have been conducted [20,21].…”

“…In this work, we propose triangular IDEs for catheter-based IRE by demonstrating electrical injury in a gastrointestinal model. The triangular IDEs allow strong electric fields to be induced at the tip of the electrode fingers and are simply fabricated using laserinduced graphene technology on a flexible polyimide film [18]. A three-dimensional finite element model based on COMSOL Multiphysics 5.4 software was adopted to investigate the enhancement in the electric field through the electrode design.…”