An electrical storage device includes a polar plate and a collector plate. The polar plate includes a mixture layer and a collector. The collector includes an exposed portion. The exposed portion is exposed from the mixture layer in one end of the polar plate in a width direction. The collector plate includes a facing portion, a projection portion, and a corner portion. The facing portion is opposed to a tip end surface of the exposed portion. The projection portion extends from the facing portion so as to project toward the exposed portion relative to the facing portion. The corner portion is placed in a boundary between the facing portion and the projection portion. The collector plate is welded to the exposed portion in at least part of the corner portion.