A EMM Fabrication Method of Metallic Bipolar Plates for PEM Fuel Cell

A prototype of metallic PEM fuel cell with thin stainless steel bipolar plates is tested for their potential applications in portable electronic products. The bipolar plate is produced by UV-LIGA and electrochemical micro-machining (EMM) technologies. The cathode electrode, the tool, is the mirror image of flow channels. It is produced by the UV-LIGA technology and the dimension is 200μm in width and 500μm in height for the intension to fabricate a serpentine flow channel of 500μm width and 200μm depth. The flow channels on 0.6mm thick SS 316L plates are fabricated by EMM process within 30 seconds with effective area of 625mm². From the results of cell performance tests, the peak power densities are 0.67 W/cm² at 0.45 V. During the 5 hours of cell life test, the cell was operated with a constant load of 0.4 V. The peak power density is stable. It just dropped slightly from 0.7 W/cm² to 0.65 W/cm². The results demonstrate the UV-LIGA and EMM technologies is an efficient method to fabricate flow channel for stainless steel bipolar plates.