Ultra-thin all-solid-state micro-supercapacitors with exceptional performance and device flexibility

Relying on the combination of lithium phosphorous oxynitride (LiPON) as electrolyte and cobalt oxide (Co3O4) as electrode material it is possible to fabricate symmetric all-solid-state micro-supercapacitors (ASTSCaps) on rigid and flexible substrates. Due to the nanoscale active layer dimensions, the excellent performance of the component materials and the high nominal voltage of 2 V, an exceptionally high volumetric energy and power densities of up to 8 (±2) mW h/cm3 and 16 (±2) W/cm3, respectively, are obtained. These results are going far beyond the current state-of-the-art performance limits. The ASTSCaps are temperature stable up to 215 °C (for 1 V nominal voltage) and experience an endurance of more than 30,000 cycles. These ultra-thin all-solid-state micro-supercapacitors bring strong benefits for on-chip energy storage and open up interesting new avenues for autonomous and flexible electronic microsystems.