1.5 kWe HT-PEFC stack with composite MEA for CHP application G. Giacoppo*, O. Barbera, A. Carbone, I. Gatto, A. Sacca `, R. Pedicini, E. Passalacqua CNR-ITAE, via S. Lucia Sopra Contesse 5, 98126 Messina, Italy article info Article history: Received 31 October 2012 Received in revised form 25 February 2013 Accepted 2 April 2013 Available online 11 May 2013 Keywords: Stack design and manufacturing High temperature PEFC Composite Nafion-YSZ MEAs PEMFC stack Flow field abstract In this work, the performance of a High Temperature (HT) Polymer Electrolyte Fuel Cell (PEFC) stack for co-generation application was investigated. A 3 kW power unit composed of two 1.5 kW modules was designed, manufactured and tested. The module was composed of 40 composite graphite cell with an active area of 150 cm 2 . Composite Mem- brane Electrode Assemblies (MEAs) based on Nafion/Zirconia membranes were used to explore the behavior of the stack at high temperature (120  C). Tests were performed in both pure Hydrogen and H 2 /CO 2 /CO mixture at different humidification grade, simulating the exit gas from a methane fuel processor. The fuel cells stack has generated a maximum power of 2400 W at 105 A with pure hydrogen and fully hydrated gases and 1700 W at 90 A by operating at low humidity grade (95/49 RH% for H 2 /Air). In case the stack was fed with reformate simulated stream fully saturated, a maximum power of 2290 W at 105 A was reached: only a power loss of 5% was recorded by using reformate stream instead of pure hydrogen. The humidification grade of Nafion membrane was indicated as the main factor affecting the proton conductivity of Nafion while the addition of the inert compound like YSZ, did not affectthe electrochemical properties of the membrane but, rather has enhanced mechanical resistance at high temperature. Copyright ª 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. 1. Introduction The development of High temperature (HT) Polymer Electro- lyte Fuel Cell (PEFC) could be an opportunity in Combined Heat and Power (CHP) systems to enhance the efficiency of a decentralized power generation and heat supplying for buildings. The main advantages with respect to other CHP systems, consists in the high efficiency of the Fuel Cells (FCs) under partial load condition, the modularity, the ability to ensure substantial autonomy of the user and, last but not least, the possible reduction of environmental pollution. In the last decade, CHP system based on PEFC have been intensively studied. Most of these are based on Nafion mem- branes which generally operates at temperature below 100  C (Low Temperature FC). Although many Low Temperature Fuel Cell, based on the use of Nafion membranes, have been indi- cated to be reliably and highly efficient, in the view of a micro- cogeneration distributed production, for domestic use [1], the interest to develop high temperature PEFC has become more relevant, due to undoubted advantages related to the use of such technology. Indeed, the increasing of the operative temperature of PEFC (>100  C) can also leads an improvement of the kinetics of reaction occurring at cathode side, a better tolerance of catalyst toward CO poisoning, an easier water * Corresponding author. Tel.: þ39 (0) 90624294. E-mail address: giacoppo@itae.cnr.it (G. Giacoppo). Available online at www.sciencedirect.com journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy 38 (2013) 11619 e11627 0360-3199/$ e see front matter Copyright ª 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijhydene.2013.04.044