Improvement of PEMFC performance and endurance by employing continuous silica film incorporated water transport plate

Abstract

An appropriate water balance between membrane dehydration and water flooding is essential to improve the performance and endurance of the polymer electrolyte membrane fuel cell (PEMFC). In this study, a novel hydrophilic porous carbon plate (HPCP) is employed as a water transport plate (WTP) to achieve the water balance by virtue of its humidification and water drainage functions. The HPCP is fabricated by electrochemically assisted self-assembly of a hydrophilic silica film on the pore surface of a porous carbon plate (PCP). To overcome the problem that the precursor is unable to enter the hydrophobic pores of the PCP, a novel electro-deposition device forcing the precursor to flow through the pores is designed. Consequently, continuous hydrophilic pores are obtained which promotes the ability of humidification and water drainage. Owing to the humidification function of the HPCP, at the current density of 1000mAcm−2, the voltage of the cell with HPCP is 270mV higher than that with solid plate (SP) under no-humidity. Attributed to the water drainage function, the runtime of the cell is twelve times longer than that with SP under dead-ended cathode operation.