<p>A battery block comprises arrayed batteries (100) which are housed within holders (20). The batteries have openings for discharging gas produced in the batteries. The holders have tube-shaped housing sections for housing the batteries. A flat plate (30) is disposed so as to be in contact with the batteries. A lid body (50) which forms a gas discharge chamber (60) between the lid body (50) and the flat plate and into which gas discharged from the openings of the batteries flows is disposed above the flat plate. The openings of the batteries are connected to the gas discharge chamber. Affixation sections (51) extending in the axial direction are formed on the lid body. Each of the affixation sections is in contact with at least a part of the side wall of each of the holders, and thus the lid body is affixed to the holders.</p>
