An elongate gas distributing tube, which extends in a longitudinal
direction of a container, is accommodated within the container that
constitutes a gas storage container. Discharge ports, through which the
gas is discharged, are provided only on a side circumferential wall of
the gas distributing tube. Therefore, the discharged gas advances while
being directed toward the inner side wall of the container. The gas
distributing tube is surrounded by a gas absorbing/adsorbing material. On
the other hand, the gas absorbing/adsorbing material is surrounded by a
mixture, which is prepared by mixing the gas absorbing/adsorbing material
with a heat storage material, such that heat is absorbed by the heat
storage material contained therein.