A conventional bipolar battery is constituted of a combination of cells hermetically sealed for preventing a liquid junction and preventing corrosion of a peripheral device due to a liquid leakage. Therefore, electrolytic solution injecting processes are carried out as many as the number of cells, so that much times and costs have been required for manufacturing a large-scale battery. In addition, a wiring space has been required since the cells are connected to one another with wires. The use of a current collector formed of a one-end closed tubular conductor, the current collector having a bottom protruding outward to form a protrusion, eliminates the wiring space and achieves a reduction in ohmic loss due to the wires. In addition, an electrolytic solution in one cell is separated by a water-repellent sheet from an electrolytic solution in another cell, so that a liquid junction is prevented.