NOVELTY - The method comprises controlling the thickness of an original material made of a porous metal having a weight per unit area of 150-350 g/m2 to form a porous metal substrate (22), filling a material mixture paste (23) comprising an active material and an elastic polymer into the substrate in a stripe pattern to form a filled portion and an unfilled portion (24), drying the substrate filled with the material mixture paste, rolling the dried substrate filled with the material mixture paste to form an electrode plate, and cutting the electrode plate into a predetermined size.    USE - Method for producing a positive electrode plate for an alkaline storage battery such as nickel-cadmium storage battery and nickel-metal hydride storage battery, which is useful as power sources for portable devices, power tools and hybrid electric vehicles.    ADVANTAGE - The method ensures economical and efficient production of the positive electrode plate with excellent current collecting efficiency, high flexibility, high energy density, high power output properties and excellent charge/discharge cycle characteristics in an environmental-friendly manner thus rapidly and effectively producing the battery with high capacity and high performance.    DETAILED DESCRIPTION - The method comprises controlling the thickness of an original material made of a porous metal having a weight per unit area of 150-350 g/m2 to form a porous metal substrate (22), filling a material mixture paste (23) comprising an active material and an elastic polymer into the substrate in a stripe pattern to form a filled portion and an unfilled portion (24), drying the substrate filled with the material mixture paste, rolling the dried substrate filled with the material mixture paste to form an electrode plate, and cutting the electrode plate into a predetermined size. A compressed gas is sprayed onto a portion of the substrate corresponding to the unfilled portion while the material mixture paste is filled into the substrate. The material mixture consists of xanthan gum, guar gum, carrageenan, diutan gum, and carboxymethyl cellulose. The filling step comprises placing die nozzles (21) facing towards each other with a gap having a predetermined width, allowing the substrate to pass through the gap in a longitudinal direction, and spraying the material mixture paste onto the passing substrate from slit-shaped outlets of the die nozzles. The distance between the die nozzle and the substrate or the flow rate of the material mixture paste sprayed from the die nozzle is controlled based on the amount of the material mixture paste filled into the substrate measured by X-ray weight analyzer or p-ray weight analyzer and/or based on the width of the filled portion on the substrate measured by an image recognition device. The slit-shaped outlet is divided into sections by a partition, and tilled portions are formed in a stripe pattern when the material mixture paste is filled into the substrate. The die nozzle comprises a combination of units, each of which has a slit-shaped outlet for spraying the material mixture paste, and filled portions are formed in a stripe pattern when the material mixture paste is filled into the substrate. The units are arranged such that their slit-shaped outlets are aligned in a line. The die nozzles are arranged such that the die nozzles face towards each other with a displacement of the positions of their slit-shaped outlets in an amount of 1-5 mm in a passing direction of the substrate. The substrate has a thickness of 200-1500 mu m and a porosity of 88-97%. The volume of the material mixture paste filled in the substrate is 95-150% of the volume of the pores of the substrate. The material mixture paste has a viscosity at 2 rpm of 10-70 Pas and a viscosity ratio: viscosity at 2 rpm/viscosity at 20 rpm of 2 or greater. The active material comprises nickel oxide particles, and the material mixture paste comprises a conductive material and water. The elastic polymer has a glass transition temperature of -100 to 20 degrees C, and the amount of the elastic polymer contained in the material mixture is 0.2-5 parts by weight per 100 parts by weight of the active material.    DESCRIPTION OF DRAWING(S) - The diagram shows an oblique view of a die coater.    Die nozzles (21)    Substrate (22)    Material mixture paste (23)    Unfilled portion. (24)