TECHNOLOGY FOCUS - POLYMERS - Preferred Compound: The polymer compound is obtained by(i) polymerizing units of formula (CH2=C(R1)C(O)O)n-A1 (I);(ii) polymerizing units of formula (II); or(iii) polymerizing units containing two or more (preferably 3) glycidyl groups arranged symmetrically with respect to a point.R1 = H or Me;A1 = hydrocarbon residue optionally containing an oxygen atom and bonded via a carbon atom (preferably hydrocarbon residue comprising ethyleneoxy group(s) and propyleneoxy group(s));n = 2-4;R2, R3 = H or Me (preferably Me for R2 and H for R3);A2 = bond or bivalent group derived from a (poly)alkyleneoxy group (preferably bivalent group of formula -(CH2-CH2-O)a-(CH2-CH(R4)-O)b-);m = 0-2 (preferably 1);R4 = H or preferably Me;a = 8;b = 2.The polymer compound is a copolymer of the unit of formula (I) or (II) and other (meth)acrylate monomer other than the units of formula (I) or (II).Preferred Units: The units of formula (I) may be represented by formula (III).The units may be 1,4-butanediol diacrylate, 2-propenone acid(2-(1,1-dimethyl-2-((1-oxo-2-propenyl)oxy)ethyl)-5-ethyl-1,3-dioxane-5-yl)methylester, ethylene glycol dimethacrylate, triethyleneglycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, and/or trimethylolpropane trimethacrylate. The units of formula (II) are glycol methacrylate, tetrahydrofurfuryl acrylate, and/or tetrahydrofurfuryl methacrylate.The units having three glycidyl groups are triglycidyl isocyanurate.Preferred Monomers: The methacrylate monomer is methyl methacrylate, ethyl methacrylate, lauryl methacrylate, or stearyl methacrylate.The acrylate monomer is isobutyl acrylate, cetyl acrylate, 3-methoxybutyl acrylate, or lauryl acrylate.Preferred Method: Step (d) comprises impregnating the solution containing the units capable of forming the crosslinked polymer compound through polymerization in the porous semiconductor layer under vacuum. Step (e) comprises impregnating the electrolyte solution in the polymer compound under heating.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Material: A solvent used in the solution containing units for forming the crosslinked polymer compound is ethylene carbonate, propylene carbonate, or N-methyl-2-pyrrolidone.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Materials: The porous semiconductor layer comprises titanium oxide or zinc oxide.The electrolyte is an oxidation-reduction electrolyte comprising iodine or iodide.