Abstract
Research on the development of all-in-one self-charging supercapacitor power cells (SCSPCs) has received
increasing attention during recent years. Herein, we reported a novel SCSPC device comprising twodimensional
graphene sheets as electrodes for energy storage and a porous PVDF incorporated TEABF4
electrolyte as a solid-like piezo-polymer separator. Initially, the energy harvesting properties of porous
PVDF films and the energy storage performance of the graphene based SCSPC device were evaluated
separately. The porous PVDF film generated a voltage from 4 to 11 V when subjected to compressive
forces of 5–20 N, respectively. The graphene SCSPC device delivered a highest specific device
capacitance of 28.46 F g1 (31.63 mF cm2) with a specific energy of 35.58 Wh kg1 and high-power
density of 7500 W kg1, respectively. Further, evaluation of the self-charging properties of the graphene
SCSPC was performed by subjecting the SCSPC device to various applied compressive forces. Strikingly,
the graphene SCSPC device can be charged up to 112 mV under a compressive force of 20 N within 250
seconds and the mechanism of self-charging via the piezo-electrochemical energy conversion process
is discussed in detail. The experimental findings on the graphene SCSPC device can provide new insights
towards the development of next-generation all-in-one energy conversion and storage devices.