Bi-polar electrode plate for storage battery array

PURPOSE: To set a pressure difference between elements within a limit value and stabilize a sealing part by providing an orifice in which a gaseous environment is communicated to a specified part of an element separator continuously combined and movement of an electrolyte is not permitted. CONSTITUTION: A storage battery array 1 is separated by a bi-polar electrode plate consisting of a conductive separator 5 having a positive electrode 6 on one face excruding an end plate 2 and having a negative electrode 7 on the other end, and an element is formed. An orifice 9 is provided so as to exceed a limit value in which a pressure difference between elements is predefined at a free part 8 free of an effective substance of the separator 5. The orifice 9 is defined by drilling a hole 103 of small diameter at the center of a water repellent plastic part 102 so that an electrolyte does not move. A storage battery is closed by a case made of a polymeric cover 3 and a bottom 4 and holding an electrode plate at a fixed position.