Components for energy storage, in particular to a process for producing a supercapacitor includes a flexible substrate, the process comprising at least the steps of unwinding the flexible substrate from a first roll, spraying a plurality of suspensions comprising micro/nanoparticles suspended in a solvent, the suspension(s) being sprayed by a plurality of nozzles, transporting at least a portion of the flexible substrate at least through a region for deposition of micro/nanoparticles, along a direction of transport of the flexible substrate, the interaction of the deposition region and of the flexible substrate forming an impact region, heating the flexible substrate, during each spraying operation, so as to encourage the complete evaporation of the solvent(s) from the suspensions sprayed onto the flexible substrate.