Unconventional thick cobalt telluride electrodes enable homogeneous ion flow for high capacity, fast and safe potassium storage

Abstract

The demand for high-energy density, fast-charging, and safe potassium-ion batteries (PIBs) is crucial for large-scale applications in electric vehicles and grid systems. Despite the potential of thick electrode designs by a conventional technique (CTEs) to boost energy density, they often encounter challenges such as reduced capacity, limited cycling lifespan, and localized short circuits. Here, we present a novel cobalt telluride composite anode by a simple tellurization and subsequent heat reduction, featuring Co1.67Te2 nanoparticles uniformly embedded within an N-doped carbon layer on a trace amount of reduced graphene oxide (CT@NC/rGO). By constructing low tortuosity electrodes (LTEs), a..