Nanostructured carbon-based electrodes: bridging the gap between thin-film lithium-ion batteries and electrochemical capacitors

The fast evolution of portable electronic devices and micro-electro-mechanical systems (MEMS) requires multi-functional microscale energy sources that have high power, high energy, long cycle life, and the adaptability to various substrates. Nanostructured thin-film lithium-ion batteries and electrochemical capacitors (ECs) are among the most promising energy storage devices that can meet these demands. This perspective presents an overview of recent progresses and challenges associated with the development of binder-free, carbon-based nanostructured electrodes prepared from layer-by-layer (LbL) electrostatic assembly, which provide enhanced gravimetric and volumetric energy for ECs and enhanced power capabilities for batteries. Based on promising findings for thin electrodes of several microns in thickness, LbL-based electrodes could also potentially be envisioned for portable electronics, electrified transportation, and load-leveling applications if successful scale-up to tens or hundreds of microns can be achieved.