A method for preparing a polymeric matrix electrode comprising: adding to a polymer matrix in liquid form an electric conductive metallic and/or a non-metallic material, wherein - the polymeric matrix is selected from the group consisting of: acrylonitrile-butadiene-styrene copolymer, ethyl-vinyl-acetate, polyacetal, polyamide 6, polyamide 12, polyamide 66, polyamide, polybutylene terephthalate, polycarbonate, polyetherketone, polyetheretherketone, polyether sulphone, polyethylene, low-density polyethylene, high-density polyethylene, polyphenylene sulfide, polyoxymethylene, polypropylene homopolymer or copolymer, polyvinylidene fluoride, and any of their possible combinations; - the electric conductive metallic and/or the non metallic material is selected from the group consisting of: carbon; graphene; fullerene; silver; copper; gold; aluminium; zinc; chrome; tin; iridium; tungsten; nickel; iron; platinum; lead; aluminium-tin oxide; indium-tin oxide; conductive ceramics; said electric conductive metallic and/or non metallic material is added at a dose of between 00% to 40%; optionally at dose of 0.1-35% with respect to the polymeric material; more optionally at a dose of 1-30%; in which: - the carbon is in the form of carbon fiber, carbon nano-fiber, carbon nanotubes, carbon black, carbon nano-clays or carbon nano-horn, - the graphene is in the form of graphene, graphene oxide, graphene, nano platelets or fullerene, - the metal is in the form of powder, dispersion, gel, particles, microparticles or nanoparticles and/or nanowire, - the conductive ceramics are in the form of powder, dispersion, gel, particles, micro-particles or nanoparticles and/or nanowire; maintaining the mixture so obtained under stirring, for a time period of 1-120 minutes, and putting the stirred mixture into a mould. adding to a polymer matrix in liquid form an electric conductive metallic and/or a non-metallic material, wherein - the polymeric matrix is selected from the group consisting of: acrylonitrile-butadiene-styrene copolymer, ethyl-vinyl-acetate, polyacetal, polyamide 6, polyamide 12, polyamide 66, polyamide, polybutylene terephthalate, polycarbonate, polyetherketone, polyetheretherketone, polyether sulphone, polyethylene, low-density polyethylene, high-density polyethylene, polyphenylene sulfide, polyoxymethylene, polypropylene homopolymer or copolymer, polyvinylidene fluoride, and any of their possible combinations; - the electric conductive metallic and/or the non metallic material is selected from the group consisting of: carbon; graphene; fullerene; silver; copper; gold; aluminium; zinc; chrome; tin; iridium; tungsten; nickel; iron; platinum; lead; aluminium-tin oxide; indium-tin oxide; conductive ceramics; said electric conductive metallic and/or non metallic material is added at a dose of between 00% to 40%; optionally at dose of 0.1-35% with respect to the polymeric material; more optionally at a dose of 1-30%; in which: - the carbon is in the form of carbon fiber, carbon nano-fiber, carbon nanotubes, carbon black, carbon nano-clays or carbon nano-horn, - the graphene is in the form of graphene, graphene oxide, graphene, nano platelets or fullerene, - the metal is in the form of powder, dispersion, gel, particles, microparticles or nanoparticles and/or nanowire, - the conductive ceramics are in the form of powder, dispersion, gel, particles, micro-particles or nanoparticles and/or nanowire; - the polymeric matrix is selected from the group consisting of: acrylonitrile-butadiene-styrene copolymer, ethyl-vinyl-acetate, polyacetal, polyamide 6, polyamide 12, polyamide 66, polyamide, polybutylene terephthalate, polycarbonate, polyetherketone, polyetheretherketone, polyether sulphone, polyethylene, low-density polyethylene, high-density polyethylene, polyphenylene sulfide, polyoxymethylene, polypropylene homopolymer or copolymer, polyvinylidene fluoride, and any of their possible combinations; - the electric conductive metallic and/or the non metallic material is selected from the group consisting of: carbon; graphene; fullerene; silver; copper; gold; aluminium; zinc; chrome; tin; iridium; tungsten; nickel; iron; platinum; lead; aluminium-tin oxide; indium-tin oxide; conductive ceramics; said electric conductive metallic and/or non metallic material is added at a dose of between 00% to 40%; optionally at dose of 0.1-35% with respect to the polymeric material; more optionally at a dose of 1-30%; in which: - the carbon is in the form of carbon fiber, carbon nano-fiber, carbon nanotubes, carbon black, carbon nano-clays or carbon nano-horn, - the graphene is in the form of graphene, graphene oxide, graphene, nano platelets or fullerene, - the metal is in the form of powder, dispersion, gel, particles, microparticles or nanoparticles and/or nanowire, - the conductive ceramics are in the form of powder, dispersion, gel, particles, micro-particles or nanoparticles and/or nanowire; maintaining the mixture so obtained under stirring, for a time period of 1-120 minutes, and putting the stirred mixture into a mould.