Table 1.

Comparison of key aspects of different IECSSs

IECSS	Solar energy‐based	Mechanical energy‐based	Thermal energy‐based	Multi energy‐based
Energy sources	Solar Energy	Wind, waves, fluids etc.	Heat from industrial wastes, geothermal activity, etc.	Combination of the solar, mechanical or thermal energies
Conversion device	Semiconductor solar cells, DSSC	Piezoelectric materials	Thermoelectric materials and devices	Multi‐conversion devices
Storage device	Supercapacitors; LIBs; hydride batteries	LIBs; Supercapacitors	Supercapacitors; TRAB	LIBs; supercapacitors
Typical integrated system configuration	Integrated Solar cell and LIBs; Integrated solar cell and supercapacitors	Piezoelectric or triboelectric materials integrated into LIBs or supercapacitors as multi‐functional separators	Liquid‐based thermoelectrochemical cells	Integrated LIBs with multi energy conversion devices
Typical overall efficiency	3.7 to 14.5%	N/A	0.1 to 5.7%	N/A