BIPOLAR PLATE, CELL FRAME, CELL STACK, AND REDOX FLOW BATTERY

A bipolar plate faces an electrode of a redox flow battery and includes an introduction channel and a discharge channel of an electrolyte. One of the introduction channel and the discharge channel is a groove-like flow channel that is formed in a surface of the bipolar plate, and the other of the introduction channel and the discharge channel is a pipe-like flow channel that is formed in an inside of the bipolar plate. The bipolar plate includes a communication hole that communicates with the pipe-like flow channel from the surface.