Performance measurements of a single cell flowing electrolyte-direct methanol fuel cell (FE-DMFC) Nasim Sabet-Sharghi a, * , Cynthia Ann Cruickshank a , Edgar Matida a , Feridun Hamdullahpur b a Mechanical and Aerospace Eng. Department, Carleton University, Ottawa, ON, Canada K1S 5B6 b Mechanical Engineering Department, University of Waterloo, Canada highlights < Demonstrating a unique design for the flowing electrolyte-direct methanol fuel cell. < Demonstrating that flowing electrolyte can remove methanol. < 3 M sulphuric acid was identified as the preferred flowing electrolyte concentration. < The effects of the flowing electrolyte on the overall performance were studied. article info Article history: Received 17 August 2012 Received in revised form 1 November 2012 Accepted 26 November 2012 Available online 21 December 2012 Keywords: Flowing electrolyte Direct methanol fuel cell Methanol crossover Nafion abstract The performance of a single cell flowing electrolyte-direct methanol fuel cell (FE-DMFC) was experi- mentally studied and its performance was compared to a regular DMFC. The active area of the fuel cell was approximately 25 cm 2 . Serpentine channels were used for both the methanol and air flows. Two combinations of Nafion Ò polymer electrolyte membranes (PEMs) were used in the MEAs. These were NR- 212/N-117 (Type 1) and NR-212/NR-212 (Type 2). For this study, diluted sulphuric acid was used as the electrolyte, which flows through a channel made of a polyethylene porous material. The flowing elec- trolyte conditions (e.g., flow rate, channel thickness and sulphuric acid concentration), the methanol concentration, and the fuel cell temperatures were varied to study how these parameters affect the overall performance of the FE-DMFC. Type 1 MEA used in conjunction with 2 M methanol produced the highest current density. The power density decreased when the thickness of the flowing electrolyte channel was increased, and the performance of the fuel cell increased when the temperature of the fuel cell was increased, as expected. The results show that the performance of the present FE-DMFC was similar to a DMFC using the same active area and a single MEA (Nafion Ò N-117). Ó 2012 Elsevier B.V. All rights reserved. 1. Introduction Direct methanol fuel cells (DMFCs) are a subset of polymer electrolyte membrane fuel cells, which use proton exchange membranes as the electrolyte and diluted methanol as fuel. Direct methanol fuel cells are primarily targeted towards small scale technologies (normally smaller than 1 kW) and relatively low operating temperatures in the range of 60e90  C [1]. This type of fuel cell is becoming more attractive when size and weight are important, as in the case of portable devices used in military operations, as well as, in other civilian applications (e.g., laptop computers, cellular phones, toys). Methanol is also easy to transport and store, requiring infrastructure similar to gasoline, which is currently available. These types of fuel cells are also competitive against current lithium-ion rechargeable batteries when power density is concerned [2,3]. There are a number of issues which exist, however, that reduce the performance of DMFCs. These include slow reaction kinetics of methanol due to the multi-step fuel oxidation process affecting anodic overpotentials [4], and the catalyst poisoning due to the intermediate hydrocarbon species produced during methanol oxidation. The most significant issue, however, related to DMFCs is the crossover of methanol from the anode to the cathode through the PEM. This latter issue significantly reduces the overall perfor- mance of the DMFC [5e9]. This study addresses the methanol crossover issue. The concept of a direct methanol fuel cell with a flowing elec- trolyte was introduced by Kordesch et al. in 2001 [10]. In this * Corresponding author. Tel.: þ1 972 54 241 4127; fax: þ1 972 4 831 3344. E-mail address: nasim84@gmail.com (N. Sabet-Sharghi). Contents lists available at SciVerse ScienceDirect Journal of Power Sources journal homepage: www.elsevier.com/locate/jpowsour 0378-7753/$ e see front matter Ó 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jpowsour.2012.11.147 Journal of Power Sources 230 (2013) 194e200