NOVELTY - Forming (m1) a solid-state device involves: applying voltage to a device comprising at least two electrodes (20,30), a combination (10) of a crosslinked gel electrolyte composition and an electroactive monomer, the combination disposed between the two electrodes, and a potential source in electrical connection with the two electrodes; where the step of applying voltage polymerizes the electroactive monomer to form a composite comprising conjugated polymer and crosslinked gel electrolyte composition (15).    USE - For forming a solid-state device selected from electrochromic device, an organic thin-film transistor, an organic light-emitting diode, or an organic photovoltaic cell (claimed).    ADVANTAGE - The method is a facile, cost effective, and industrially scalable method. The device can be fully assembled prior to the application of the voltage which effects the formation of the conjugated polymer via electrochemical polymerization. Such a process avoids many of the usual processing steps required to make such solid-state devices e.g. an electrochromic device (ECD). Such steps that are avoided include formation of a discrete, thin film of conjugated polymer on a substrate, formation of an electrolyte bath used for electrodeposition, disposal of the electrolyte bath. There is also no need for special processing steps for device assembly, special synthetic steps for conjugated polymer preparation, and there is a significant avoidance of chemical waste in that electrolytic baths containing solvents and organic salts are not used. Unlike traditionally formed conjugated polymer films prepared via electrochemical deposition that are then used to form an assembled device, the conjugated polymer is not formed as a discrete thin-film, but rather a polymer composite with the electrolyte composition. For e.g. when a gel electrolyte is used, the conjugated polymer is formed as a composite with the gel electrolyte matrix. With this process, it is possible to form a variety of complex blends.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for the solid-state device prepared by the method (m1) and comprising: at least two electrodes; and a composite disposed between the at least two electrodes, the composite comprising a conjugated polymer and a crosslinked gel electrolyte composition, where the conjugated polymer is not formed as a discrete film.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic procedure for the in situ polymerization of electroactive monomer into a conjugated, conducting, electrochromic polymer inside an assembled solid-state device.    Electrochrome electrolyte blend (5)    Combination of crosslinked gel electrolyte composition and electroactive monomer (10)    Crosslinked gel electrolyte composition (15)    Electrodes (20,30)    Substrate layer (40,50)