NOVELTY - A metal-gas battery comprises metal-gas cell (12) having soft pocket (24) with two flexible and planar walls, two groups of threads, two gas cathodes (18), two soft plates, rigid planar first retaining structure (38) and rigid planar second retaining structure (42), metal anode (28) disposed in the soft pocket chamber, two sheets of separator, and sub-assembly (32) located in an upper-most position of the metal-gas cell.    USE - The invention is for use as a metal-gas battery, e.g. zinc-air battery (claimed). It can be used for rapid refueling.    ADVANTAGE - The invention can be conveniently recharged through mechanical replacement of metal anode. It eliminates the expensive and labor-intensive operation of changing and washing the separator bags. It does not leak electrolytes or electrolyte mist, and is sufficiently durable for hundreds of refueling operations.    DETAILED DESCRIPTION - Metal-gas battery comprises metal-gas cell having soft pocket with two flexible and planar walls, two groups of threads vertically arranged and glued into the peripheries of the two walls of the soft pocket to form a gas passage between adjacent threads, two gas cathodes glued to the two walls of the soft pocket, two soft plates with a central opening (65) used to help to seal the two gas cathodes to the two walls of the soft pocket, rigid planar first retaining structure and rigid planar second retaining structure attached to the peripheries of the two walls of the soft pocket, metal anode disposed in the soft pocket chamber, two sheets of separator permanently and respectively installed between each pair of the gas cathode and group of threads, and sub-assembly located in an upper-most position of the metal-gas cell. The peripheries of the two walls are connected except along respective top edges of the two walls. The soft pocket is made of an elastic and alkaline-resistant material. The two gas cathodes are permeable to air but impermeable to liquids to allow gases to enter the metal-gas cell. They are electrically connected to each other. The two gas cathodes and two walls of the soft pocket cooperate to define a liquid retaining soft pocket chamber having a lower portion (66), upper portion (64), and top opening defined between the top edges of the two walls of the soft pocket. The soft plates are made of a same material as the soft pocket. The second retaining is moveable with respect to the first retaining structure between a first and second retaining structure positions. The first retaining structure is proximal to the second retaining structure to close tightly the top opening of the soft pocket chamber. The sub-assembly is permeable to air but impermeable to liquids to reduce a pressure difference between the soft pocket chamber and outside atmosphere.    DESCRIPTION OF DRAWING(S) - The figure is a perspective view of a metal-gas cell useable in the metal-gas battery.    Metal-gas cell (12)    Gas cathodes (18)    Soft pocket (24)    Metal anode (28)    Sub-assembly (32)    Rigid planar first retaining structure (38)    Rigid planar second retaining structure (42)    Electrically conductive support structure (62)    Upper portion (64)    Central opening (65)    Lower portion (66)    Metal powder (68)    Hole (152)