NOVELTY - The dry method of making a gas diffusion electrode, comprises forming an intimate fibrillated mixture of catalytically active carbon particles (30-95 wt.%) and particles (5-35 wt.%) of a wet-proofing agent into a web, calendering the web with a current collector under pressure to form a current collector-web composite, and attaching a porous sheet of a fluorinated polymer to one side of the current collector-web composite to form a gas diffusion electrode. The intimate mixture is prepared by treating the carbon particles and the polymer particles in a milling machine and a chopping machine.    USE - The dry method is useful for making a gas diffusion electrode such as an air cathode, which is useful in a direct liquid fuel cell and portable fuel cell and in metal-air battery (all claimed), where the fuel cell and metal-air battery are useful to supply electrical energy to a virtually unlimited number of electric and electronic devices such as cellular phones, portable computers, personal digital assistants, consumer electronics, portable medical devices and components and peripherals, and as a generator for emergency situations such as a power outage.    ADVANTAGE - The method is capable of economically and easily making the gas diffusion electrode with improved properties, high efficiency and high specific energy capacity thus improving the performances of the fuel cell and metal-air battery, and avoids the need to remove the solvent and the environmental and other fire hazard problems.    DETAILED DESCRIPTION - The dry method of making a gas diffusion electrode, comprises forming an intimate fibrillated mixture of catalytically active carbon particles (30-95 wt.%) and particles (5-35 wt.%) of a wet-proofing agent into a web, calendering the web with a current collector under pressure to form a current collector-web composite, and attaching a porous sheet of a fluorinated polymer to one side of the current collector-web composite to form a gas diffusion electrode. The intimate mixture is prepared by treating the carbon particles and the polymer particles in a milling machine, a chopping machine and a beating machine in absence of added solvent, and comprises pore-forming particles (65 wt.%) having an average particle size of 1-100 mu m and a specific surface area of 500-2000 m2/g. The catalytically active carbon particles have an average particle size of 6-50 mu m and a specific surface area of 300-1000 m2/g. The pore-forming particles comprise electrically conductive particles with carbon particles. The particles of a wet-proofing agent comprise fluorinated polymer particles having an average particle size of 10-500 mu m. The web has a thickness of 0.2-0.6 mm. The current collector comprises a metal mesh and a metal cloth both having a thickness of 0.12-0.4 mm, a metal grid, and a metal foam having a thickness of 0.5-2 mm. The web and the current collector are passed together through a calender. The current collector web composite has a thickness of 0.2-0.6 mm. The sheet of a fluorinated polymer has a thickness of 0.1-0.35 mm and an average pore size of 0.05-2 mu m. The gas diffusion electrode has a thickness of 0.25-0.75 mm. INDEPENDENT CLAIMS are included for:    (1) a gas diffusion electrode;    (2) a fuel cell;    (3) a metal-air battery; and    (4) a method of supplying energy to an electrical device.    DESCRIPTION OF DRAWING(S) - The figure shows a device to obtain the polarization curves of the air cathode.