Prospects of different fuel cell technologies for vehicle applications C. Bernay a,b , M. Marchand a,* , M. Cassir b a Renault Technocentre, 1 avenue du Golf, 78288 Guyancourt Cedex, France b Ecole Nationale Supe ´rieure de Chimie de Paris, Laboratoire d’Electrochimie et de Chimie Analytique (UMR 7575 du CNRS), 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France Received 27 August 2001; accepted 22 December 2001 Abstract Two potential applications of fuel cell power plants in passenger cars: drive and auxiliary power units are presented. Then, specific constraints for fuel cell stack and power plants are evaluated for each application. After the description of the different fuel cell technologies, they are compared mainly at the stack level and power plant level if significant, depending on various criteria corresponding to the different vehicle applications. Finally, technologies of potential interest for use in vehicles are evaluated. Proton exchange membrane fuel cell (PEMFC), providing short starting and response times at the stack level seems the most suitable technology for drive application. In an auxiliary power unit application, the solid oxide fuel cell (SOFC), which allows easier operating with a traditional engine fuel because of simplified fuel processing and presents good performance, may find an application. # 2002 Elsevier Science B.V. All rights reserved. Keywords: Fuel cells; PEMFC; SOFC; Vehicle; Fuel processing; Auxiliary power unit 1. Introduction Important research and development efforts are deployed by car manufacturers to develop fuel cell vehicles, planned for start of production 2003–2005 by Honda, Ford, Toyota, General Motors, Daimler–Chrysler and Renault/Nissan [1]. The Californian market is considered the leader for fuel cell vehicles today. Actually, from 2003 on, 10% vehicles being sold by manufacturers should meet ZEV requirement. Only pure electric vehicles and hydrogen fuel cell vehicles can presently achieve‘‘Zero Emission Vehicle’’. To implement such a rapid transition, the California Fuel Cell Partnership (CAFCP) has been established to demonstrate fuel cell vehicles. The CAFCP units car manufacturers (Daimler– Chrysler, Ford, General Motors, Honda, Hyundai, Nissan, Toyota and Volkswagen), energy companies (BP, Shell, Texaco and Exxonmobil), proton exchange membrane fuel cell (PEMFC) manufacturers (Ballard Power Systems and International Fuel Cells), government partners (including CARB) and associate partners (Air Products and Chemicals Inc., Praxair, Methanex Corporation) [2]. Mostly, all of the car manufacturers, however, plan a subsequent market penetration in 2010. Until now, fuel cells are planned mainly for the drive application. However, other vehicle applications may be considered for this power source such as auxiliary power units. A fuel cell technology attracting most of the invest- ment is the PEMFC. Though this technology achieves, today, power densities compatible with drive applications, it shows nevertheless, some drawbacks. For a fuel other than hydrogen, the sensitivity of the PEMFC to CO requires the installation of at least two reformate purification stages, which results in increasing the volume and complexity of the fuel supply system. California State has, therefore, chosen hydrogen and not methanol, on board of a fuel cell vehicle [3]. Besides, though the PEMFC operating temperature is com- patible with short start and response times, a higher tem- perature (above 120–130 8C) would make the evacuation of generated heat easier. Nevertheless, the cost of a PEMFC drive train is still expensive as compared with the cost of a traditional engine. Lately, a direct methanol fuel cell (DMFC)-based drive train has been demonstrated in a prototype by Daimler–Chrysler [4] and solid oxide fuel cell (SOFC) as a power unit by BMW. Among other fuel cell technologies such as, for example, the DMFC or the SOFC, would some of them have more potential than the PEMFC? For which vehicle application? What type of fuel cell technology will be used in a vehicle beyond 2010? This article is intended to give some answers to these questions by comparing the different fuel cell technologies, Journal of Power Sources 108 (2002) 139–152 * Corresponding author. Tel.: þ33-1-30-50-7723; fax: þ33-1-30-50-7751. E-mail address: marielle.marchand@renault.com (M. Marchand). 0378-7753/02/$ – see front matter # 2002 Elsevier Science B.V. All rights reserved. PII:S0378-7753(02)00029-0