PEM Fuel Cell Applications

Since PEM fuel cells ean generate power from a fraction of a watt to hundreds of kilowatts, they can be used in almost any application, from stationary power to vehicles of all sizes down to mobile phones. The application areas of PEM fuel cells with a variety of power levels are listed in Table 1.4. 

1 kW-lOkW Transportation vehicles such as motorcycles, utility vehicles, cars, yachts various portable power devices used for field working, underwater platform backup power unintermptible power, residential power system 

100 W-1 kW Simple riding devices such as bicycles, scooters, and wheelchairs backpack power power for exhibition or demo UPS for small services, terminals, and computers 

10 W-IOOW Portable power such as for emergency working power supply and military equipment battery replacements lighting signal light power 

The development of PEM fuel cell technology and the demonstration of its application to transportation vehicles have grown rapidly in the last 15 years. In 1993, Ballard demonstrated the first PEM fuel cell-powered bus. Then, following the announcement of the first fuel cell stack with a power density of 1 kW/1, a 

---

D.R. Vernon, F. Meng, S.F. Dee, D.L Williamson, J.A. Turner, and A.M. Flerring, Synthesis, Characterization, and Conductivity Measurements of Hybrid Membranes Containing a Mono-lacunary Heteropolyacid for PEM Fuel Cell Applications,/. Power Sources, 139, 141-51 (2005). 

Perfluorinated membranes are still regarded as the best in the class for PEM fuel cell applications. - These materials are commercially available in various forms from companies such as DuPont, Asahi Glass, Asahi Chemical, 3M, Gore, and Sol-vay. Perfluorosulfonic acid (PFSA) polymers all consist of a perfluorocarbon backbone that has side chains terminated with sulfonated groups. 

PBI (see chemical structure above) is a hydrocarbon membrane that has been commercially available for decades. Free PBI has a very low proton conductivity ( 10 S/cm) and is not suitable for PEM fuel cell applications. However, the proton conductivity can be greatly improved by doping PBI with acids such as phosphoric, sulfuric, nitric, hydrochloric, and perchloric acids. The PA-doped PBI membrane is the most popular one in PEM fuel cell applications because H3PO4 is a nonoxidative acid with very low vapor pressure at elevated temperature. Savinell et al. and Wainright et al. first demonstrated the use of PBI-PA for HT fuel cells in 1994.270 272 since then, there has been a significant amount of research on the PBI-based membrane because of its low cost and good thermal and chemical stabil-... 

Polyarylenes, in particular different types of poly(arylene ether ketone)s, have been the focus of much hydrocarbon membrane research in recent years. - - With good chemical and mechanical stability under PEM fuel cell operating conditions, the wholly aromatic polymers are considered to be the most promising candidates for high-performance PEM fuel cell applications. Many different types of these polymers are readily available and with good process capability. Some of these membranes are commercially available, such as poly(arylene sulfone)s and poly(arylene... 

Miyake, N. et ah. Durability of Asahi Kasei Aciplex membrane for PEM fuel cell application, in Proceedings of the 206th ECS Meeting Proton Conducting Membrane Fuel Cells IV, Honolulu, HI, October 3-8, 2004, p. 333. 

Dante, R. (2004). Hypotheses for direct PEM fuel cells applications of photobiopro-duced hydrogen by Chlamydomonas reinhardtii. Int.. Hydrogen Energy (in press). 

Gokaliler, F., Selen aglayan, B., Ilsen Onsan, Z., and Erhan Aksoylu, A. Hydrogen production by autothermal reforming of LPG for PEM fuel cell applications. International Journal of Hydrogen Energy, 2008, 33 (4), 1383. 

Castaldi, M.J., Boorse, R.S., Roychoudhury, S., Menacherry, P., and Pfefferle, W.C. Lightweight, Compact, Ultra-fast Short Contact Time Preferential Oxidation Reactor for Automotive PEM Fuel Cell Applications, NSF National Meeting (ed. National Science Foundation). San Juan, Puerto Rico National Science Foundation, January 2002. 

Caternillar Onerates PEM Fuel Cell stack on Ethanol Reformate Caterpillar, Nuvera Fuel Cells, and Williams Bio-Energy have teamed to develop and demonstrate a 15-kW ethanol-fueled PEM fuel cell system. The primary technical objectives of this project are to demonstrate performance, durability and reliability and to understand correlations and reduce gaps between stationary and transportation PEM fuel cell applications. Power module design specifications have been completed. The reformer has been tested for a short period of time (45 minutes) on ethanol at rated power, and 45- and 80-cell stacks have been successfully tested with output from the reformer. 

Overall, composite bipolar plates have been used successfully in many PEM fuel cell applications including fuel cells for vehicle propulsion. 

Carbon cloth (CC) is another kind of GDL used for PEM fuel cell application. Typically carbon cloth is thicker than the average carbon paper but has the important advantage of being flexible. Regarding the through plane electrical... 

Dicks AL (2012) PEM fuel cells applications. Compr Renew Energy 4 203-245... 

Tian, S.H., Shua, D., Chen, Y.L., Xiao, M. and Meng, Y.Z. 2005. Preparation and properties of novel sulfonated poly(phthalazinone ether ketone) based PEM for PEM fuel cell application. J. Power Sour. 158 88-93. 

The long-term stability of Pd-based electrocatalysts is one of the unavoidable issues for PEM fuel cell applications. Pd-Pt-based ORR catalysts are more stable than Pd-transition metal alloys under harsh fuel cell conditions, but may still not meet the long-term fuel cell operation requirement due to the Pd leaching out. Future research may focus on improving the durability of Pd-based catalysts by surface modification and composition optimization. Core-shell type of catalyst with Pd-based materials as the core and Pt as the shell may be one of the most promising candidates to be used in the automotive fuel cell due to its low Pt content and high activity and stability. 

Smirnova A, Dong X, Hara H, Vasiiiev A, Sammes N (2005) Novel carbon aerogel-supported catalysts for PEM fuel cell application. Int J Hydrogen Energy 30(2) 149-158... 

Within the renewed research area of hydrogen production for PEM fuel cell application, the non-stationaiy catalytic decomposition of methane into CO free hydrogen via a cyclic two-step process spears as a promising alternative to the stationary reforming as suggested in [3-5] ... 

Li, L. and King, D.L. (2006) H2S removal with ZnO during fuel processing for PEM fuel cell applications. Catal. Today, 116, 537-541. 

Higgins DC, Chen Z (2013) Recent progress in non-precious metal catalysts for PEM fuel cell applications. Can J Chem Eng 91 1881-1895... 

Although platinum and platinum alloys are the state-of-the-art electrocatalysts for PEM fuel cell applications, the platinum loading required to reduce the effective overpotential of the oxygen reduction reaction at high current densities (1-2 A/cm )... 

Borup RL, Vanderborgh NE. Design and testing criteria for bipolar plate materials for PEM fuel cell applications. Mat Res Soc Symp Proc 1995 393 151-5. 

Based on the above review of the ORR activity of Pt alloys, it appears Pt-based alloys can improve specific activity and mass activity by several times relative to pure Pt catalyst in both an acid electrolyte and a real PEM fuel cell environment. In particular, the reported Pt3Ni(lll)-skin surface, which exhibits the most remarkable ORR catalytic activity that has ever been detected, looks very promising in terms of further activity improvement of Pt alloy catalysts for PEM fuel cell applications. The remaining challenge is how to create a fuel cell nanocatalyst with electronic and morphological properties that mimic the Pt3Ni(l 11) surface. 

A major challenge in the synthesis of CNTs and CNFs as supports for Pt electrocatalysts is to control the size and distribution of the Pt nanoparticles. Since the dispersion and particle size of Pt on the support material can strongly affect its utilization and catalytic activity [2], the synthesis of Pt nanoparticles supported by CNTs and CNFs are of fundamental and practical importance [63, 68, 76-79]. In a recent review, Lee et al. [80] described the various synthesis methods of the Pt electrocatalyst using CNTs and CNFs as flie support of the Pt catalyst in the PEM fuel cell applications. The deposition, distribution, and crystalline size of Pt nanoparticles supported on CNTs and CNFs are significantly affected by factors including the synthesis method, oxidation treatment of CNTs and the Pt precursors. In this section, we will focus on the synthetic methods of depositing Pt nanoparticles onto CNTs and their morphology. 

Cabot s Dynalyst family of electrocatalysts is designed for use in applications ranging from cost-sensitive to performance-driven PEM fuel cell applications. Dynalyst electrocatalyst powders are manufactured to meet specific performance requirements based on their structure, composition and precious metal loading in the electrode layers. Dynalyst 20SR1 - 20% Pt/C electrocatalyst has excellent electrochemical performance at low precious metal loadings in the MEA. A loading of 0.1-0.3 mg Pt/cm in the electrode layer is recommended to achieve optimum performance and Pt utilization. 

Chellappa, A.S., C.M. Fischer, and W.J. Thomson. 2002. Ammonia decomposition kinetics over Ni-Pt/ AI2O3 for PEM fuel cell applications. Appl. Catal. A Gen. 227 231-240. 

Equation (3.26) can also be used to estimate the threshold toluene concentration in the air stream for a given performance requirement (MPD %) at a given current density. For example, if 10% MPD is the acceptable performance threshold for a specific PEM fuel cell application, the threshold toluene concentration would be 48.1 ppm at 0.5 A cm and 4.5 ppm at 1.0 A cm. ... 

The outlet hydrogen stream from a PSA unit contains CO concentrations higher than 100 ppm. For PEM fuel cell applications, to reach acceptable CO concentrations 10 ppm at Pt anodes and <100 ppm at CO-tolerant alloy... 

---