Research On Design And Electrochemical Performance Of All-in-one Configured Supercapacitor

With the continuous development of wearable electronic devices,the corresponding flexible energy storage devices have also received more and more attention.As important energy storage devices,supercapacitors are develop i ng toward the trend of flexibility and miniaturization due to their fast charging and discharging rates in order to meet the requirements of wearable electronic devices.In general,flexible supercapacitors are composed of solid-state electrodes and gel electrolytes.In practical applications,when multiple compressions,stretching and bending occurs,sub-layers are easily subdivided and misaligned,resulting in failure of the device;The discarded e-wastes are also harmful to our environment.It is necessary to design an al-in-one configured supercapacitor that can withs t a nd compression,stretching and bending,as well as a self-healing biodegradable al-inone configured supercapacitor.Intrinsic compressible stretchable electrolyte is the core of an intrinsica l l y compressible stretchable al-in-one configured supercapacitor.A polyacrylic acid（PAA）hydrogel which can achieve 60% compressive strain and 900% tensile strain was prepared by thermal polymerization.The electrode-electrolyte-integrated al-inone supercapacitor was obtained by directly growing the electrode material on the hydrogel by in-situ growth method.The supercapacitor has better electrochem ica l performance.The supercapacitor has an area specific capacitance of 0.056 m F cm^-2 at a current density of 1.7 μA cm^-2.The supercapacitor simultaneously achieves dual functions of compression and stretching.when the supercapacitor is under compressive strain from 0% to 60%,and the CV and GCD curves of the capacitor remain superposed,and the capacitance retention rate is about 100%.The supercapacitor can also withstand 150% tensile strain.Intrinsic self-healing electrolytes and electrodes are important prerequisites for intrinsic self-healing al-in-one configured supercapacitors.In order to achieve selfhealing properties,an electrolyte layer based on flour,an electrode layer based on flour and activated carbon as an active material was prepared.An electrod e-electrolyte-integrated al-in-one configured supercapacitor was successful l y fabricated based on the flour matrix of the electrolyte and the electrode.The supercapacitor has a better volumetric capacitance value with an area specific capacitance of 0.13 m F cm^-3 at a current density of 5 μA cm^-3.The supercapacitor has excellent self-healing ability.During 40 cutting/healing processes,the CV,GCD and EIS curves of the capacitor are completely coincident with the curves of initial state,and the capacitance retention is close to 100%.The supercapacitor can still achie ve 50% tensile strain after one healing,and the capacitance retention is about 75%.In the end,the supercapacitor can also realize the decomposition in the simulated gastr ic juice and soil,achieving a process of from the nature and to the nature.