Lin T.-YLiu Y.-HPan K.-LSun K.K.-E.KUO-LONG PAN2021-08-052021-08-052018https://www.scopus.com/inward/record.uri?eid=2-s2.0-85079774234&partnerID=40&md5=22a012b216b2c520bf557eb2b9decb4chttps://scholars.lib.ntu.edu.tw/handle/123456789/576174Water flooding in a polymer electrolyte membrane fuel cell (PEMFC) is a critical problem for substantially lowering the cell efficiency. To find an efficient way for removing water readily at desired flow conditions, we have devised a four-layered multi-U-shaped microchannel with drainage branches. In the flow patterns of wetting bubbles, water was effectively drained out while air remained in the channel without leaking through the branches. The gas/liquid transport could be further facilitated by adding a small amount of surfactant. The mechanisms were then tested in a PEMFC. Without need of raising temperature or sophisticated operation as conducted in many studies, the efficiency was significantly increased and higher stability was achieved. The device can be easily scaled up for using stacks of such cells. Copyright ? (2018) by Chemical and Biological Microsystems Society. All rights reserved.Efficiency; Fuel cells; Microchannels; Microfluidics; Polyelectrolytes; Surface active agents; Two phase flow; Wetting; Bubble; Cell efficiency; Critical problems; Flow condition; PEM fuel cell; Scaled-up; U-shaped; Water removal; Proton exchange membrane fuel cells (PEMFC)[SDGs]SDG7conference paper2-s2.0-85079774234