NOVELTY - The device has a valve element (3) e.g. on-tank-valve, including a pressing section (10) enclosed by a collar inner wall (6). An outer diameter (D) of the pressing section before a valve element assembly is larger than a diameter (d) of the collar inner wall so that a permanent press fit is produced between the pressing section and the collar inner wall, and between a collar outer wall (5) and an inner wall (9) of a valve connecting element (2) during assembling the valve element. The press fit seals a pressurized medium. A medium container (1) is surrounded by a reinforcement layer (14).    USE - Device for storing and dispensing pressurized fluid and/or gaseous media i.e. hydrogen, to a fuel energy conversion device of a motor car (all claimed), where the conversion device converts the fuel i.e. hydrogen, into electrical energy for an electric motor and a traction battery.    ADVANTAGE - The outer diameter of the pressing section before the valve element assembly is larger than the diameter of the collar inner wall so that the permanent press fit is produced between the pressing section and the collar inner wall, and between the collar outer wall and the inner wall of the valve connecting element during assembling the valve element, where the press fit seals the pressurized medium, thus avoiding the need for a separate additional sealing element, and ensuring an improved and permanent sealing tightness using a smaller number of sealing elements.    DETAILED DESCRIPTION - The reinforcement layer includes filaments made of carbon, glass, polyamide, mineral substance, or combination. INDEPENDENT CLAIMS are also included for the following:    (1) a fuel energy conversion device    (2) a method for assembling a device for storing and dispensing pressurized fluid and/or gaseous media.    DESCRIPTION OF DRAWING(S) - The drawing shows an axial longitudinal sectional view of a device for storing and dispensing pressurized fluid and/or gaseous media before assembly of the valve element.    Diameter of a collar inner wall (d)    Outer diameter of a pressing section (D)    Medium container (1)    Valve connecting element (2)    Valve element (3)    Collar outer wall (5)    Collar inner wall (6)    Opening (8)    Inner wall of valve connecting element (9)    Pressing section (10)    Reinforcement layer (14)