Water transport in polymer membranes for PEMFC

Choi, Kihwan; Peck, Dong‐Hyun; Kim, Chang Soo; Shin, Dong-Ryul; Lee, Tae Hee

doi:10.1016/s0378-7753(99)00420-6

Cited by 83 publications

(35 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A proton exchange membrane fuel cell (PEMFC) is a prospective alternative power source for short-term space missions because of the following characteristics: high-energy conversion efficiency, zero emission, low temperature, and regenerative operation [1][2][3]. In space engineering, PEMFCs with polystyrene membranes were first applied to the GEMINI spacecraft in the 1960s [4].…”

Section: Introductionmentioning

confidence: 99%

Experimental study of two-phase flow in a proton exchange membrane fuel cell in short-term microgravity condition

Guo

Zhao

et al. 2014

Applied Energy

View full text Add to dashboard Cite

h i g h l i g h t sTwo-phase flow in PEMFC cathode channels is observed in different gravity environments. The PEMFC shows different operating behavior in normal and microgravity conditions. Water tends can be removed in microgravity conditions at high water production regime. Liquid aggregation occurs in microgravity conditions at low water production regime. Effect of gravity on performance and two-phase flow at two operating regimes is studied. a r t i c l e i n f o t r a c tWater management is important for improving the performance and stability of proton exchange membrane fuel cells (PEMFCs) for space applications. An in situ visual observation was conducted on the gasliquid two-phase flow in the cathode channels of a PEMFC in short-term microgravity condition. The microgravity environment was supplied by a drop tower. A single serpentine flow channel with a depth of 2 mm and a width of 2 mm was applied as the cathode flow field. A membrane electrode assembly comprising of a Nafion 112 membrane sandwiched between gas diffusion layers was used. The anode and cathode were loaded with 1 mg cm À2 platinum. The PEMFC shows a distinct operating behavior in microgravity because of the effect of gravity on the two-phase flow. At a high water production regime, cell performance is enhanced by 4.6% and the accumulated liquid water in the flow channel tends can be removed in microgravity conditions to alleviate flooding. At a low water production regime, cell performance deteriorates by 6.6% and liquid aggregation occurs in the flow channel because of the coalescence of dispersed water droplets in microgravity conditions, thus squeezing the flow channel. The operating behavior of PEMFC in microgravity conditions is different from that in normal gravity conditions. Further studies are needed on PEMFC operating characteristics and liquid management for space applications.

show abstract

Section: Introductionmentioning

confidence: 99%

Experimental study of two-phase flow in a proton exchange membrane fuel cell in short-term microgravity condition

Guo

Zhao

et al. 2014

Applied Energy

View full text Add to dashboard Cite

show abstract

“…The strong dependence of conductivity on hydration clearly indicates that absorbed water is facilitating proton conduction. The absorbed water molecules not only can transport proton through the hydronium ion (H 3 O þ , H 5 O 2 þ and H 9 O 4 þ ), but also bridge the functional phosphonic acid groups for proton transfer [33]. Thus, the absorbed water molecules in the high membrane contribute to the proton conduction by both Grotthuss and vehicle mechanisms under the fully hydrated state.…”

Section: Nmr Analysis Of the Hybrid Membranesmentioning

confidence: 99%

Synthesis and characterization of high temperature proton exchange membrane from isocyanatopropyltriethoxysilane and hydroxyethane diphosphonic acid

Shen

Kong

Wang

et al. 2015

International Journal of Hydrogen Energy

View full text Add to dashboard Cite

“…The model also includes an electro-osmotic drag of water from the anode flow channel through the term k w eo (i/Ᏺ). The electro-osmotic mass-transfer coefficient has been experimentally found to depend stronger than linearly on the water activity in the membrane 32,[35][36][37] ; the data were approximated by the form k w eo ϭ 2(a w A ) 4 ϭ 2(P w A / P wo ) 4 . Most of our results found electro-osmotic drag was only important at large current densities (Ͼ1 A/cm 2 ), 38 and were not important for most of the conditions studied in this article.…”

Section: Str-pem Fuel Cellmentioning

confidence: 99%