NOVELTY - The gas diffusion layer comprises a substrate from a carbonaceous material and/or a microporous layer, where the gas diffusion layer is obtainable by a method comprising dispersing a soot with a Brunauer-Emmett-Teller (BET) surface of maximum 200 m2/g, carbon nano-small tubes with the BET-surface of 220-280 m2/g and an average outer diameter of 12-18 nm and/or a dispersion medium containing a mixture having a shear rate of 5000 S-1 so that, in the manufactured dispersion of 90%, the carbon nano-small tubes have an average agglomerate size of less than 15 mu m.    USE - The gas diffusion layer is useful in fuel cells such as electrochemical cells, electrolytic cells and batteries.    ADVANTAGE - The gas diffusion layer can be economically manufactured with improved electric conductivity and gas permeability and less consumption of power.    DETAILED DESCRIPTION - ETAILED DESCRIPTION - The gas diffusion layer comprises a substrate made of a carbonaceous material and/or a microporous layer, where the gas diffusion layer is obtainable by a method comprising dispersing a soot with a Brunauer-Emmett-Teller (BET) surface of maximum 200 m2/g, carbon nano-small tubes with the BET- surface of 220-280 m2/g and an average outer diameter of 12-18 nm and/or a dispersion medium containing a mixture having a shear rate of 5000 S-1 so that, in the manufactured dispersion of 90%, the carbon nano-small tubes have an average agglomerate size of less than 15 mu m, applying the manufactured dispersion on a section of one side of the substrate, and drying the manufactured dispersion. The used mixture: contains water as dispersion medium, where an amount of the dispersion medium related to the total quantity of the mixture is 87-94 wt.%; and have a carbon portion of 25-35 wt.%. The amount of carbon nano-small tubes related to the carbon portion of the microporous layer is present in the range of 25-35 wt.%. The dispersing step is performed in a ball mill, a perl mill, a sand mill, a kneader, a rolling chair, a static mixer, an ultrasound disperser and a device, which introduces shear forces by high pressures, accelerations and/or percussion. The gas diffusion layer has a compression of 100 N/cm2, an electric resistor of less than 8 Omega .cm2, and a Gurley gas permeability of more than 2 cm3/cm2/s. The microporous layer (77-90 wt.%) is composed of binding agent, soot and/or carbon nano-small tubes. A catalyst layer is located on the microporous layer.