Micro-ECM of Maze Flow Channel on Bipolar Plates of Fuel Cell

Abstract

A lot of flow channels should be processed on stainless steel bipolar plates of fuel cell. In order to increase contact area of gas with electrode and ensure the gas flowing smoothly, the flow channels will be multichannel maze. It is difficult to be machined by conventional methods, because the width and depth of the flow channels are very small (about 300μm). When using micro electrochemical machining, flow channels with low surface roughness and good machining accuracy could be produced efficiently. The machining cathode tool, fixture, μ-second grade pulse power supply and machining parameters are introduced. Using microsecond pulse current processing, the maze-shaped flow channel on bipolar plates of fuel cell can be processed seccessfully, with high efficiency and good quality. Thus graphite bipolar plates may be replaced by metal bipolar plates. It may promote the technology advancing for fuel cell, and reducing its cost. Key factors for influencing electrochemical machining process of flow Channels on bipolar plates include the design of cathode and fixture , microsecond pulse current, and suited technical parameters