Capacitive energy storage in micro-scale devices: recent advances in design and fabrication of micro-supercapacitors

TLDR

Miniaturized energy storage is essential for the continued development of electronic devices, and micro‑supercapacitors—electrochemical capacitors with high power density, fast charge/discharge, and long life—can be integrated with microelectronics to serve as stand‑alone power sources or complement batteries and harvesters, with recent advances improving their storage capacity and power density. This review examines recent advances in the fabrication of micro‑supercapacitor materials and devices and critically evaluates reported performance metrics. It analyzes how electrode material properties, electrolyte composition, device architecture, and fabrication techniques influence micro‑supercapacitor performance.

Abstract

Miniaturized energy storage is essential for the continuous development and further miniaturization of electronic devices. Electrochemical capacitors (ECs), also called supercapacitors, are energy storage devices with a high power density, fast charge and discharge rates, and long service life. Small-scale supercapacitors, or micro-supercapacitors, can be integrated with microelectronic devices to work as stand-alone power sources or as efficient energy storage units complementing batteries and energy harvesters, leading to wider use of these devices in many industries. In recent years, the research in this field has rapidly advanced and micro-supercapacitors with improved storage capacity and power density have been developed. The important factors affecting the performance of micro-supercapacitors are the intrinsic properties of electrode materials and electrolyte, architectural design of the device and the fabrication methods. This paper reviews the recent advances in fabrication of materials and devices and provides a critical analysis of reported performances of micro-supercapacitors.