To provide a battery that is used for a storage system for power storage through improvement of strength of itself in accordance with its increasing size.

The battery is provided with at least two opposing collectors with a honeycomb structure having a through-hole each. On opposing faces of the collectors, an outer shape of the through-hole of one of the collectors is so structured not to overlap with that of the other collector, with strength enhanced. Preferably, a material of the collector is a kind selected from aluminum, copper, nickel, iron, stainless steel or the like.