Impact of Thickness of Polymer Electrolyte Membrane and Gas Diffusion Layer on Temperature Distributions in Polymer Electrolyte Fuel Cell Operated at Temperature around 90 °C

Abstract

Polymer Electrolyte Fuel Cell (PEFC) is desired to be operated at temperature around 90 °C for stationary applications during the period from 2020 to 2025 in Japan. It can be expected thinner polymer electrolyte membrane (PEM) and gas diffusion layer (GDL) would promote the power generation performance of PEFC at this temperature. The aim of this study is to understand the impact of thickness of PEM and GDL on the temperature profile of interface between PEM and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC with an initial operation temperature (T ini). An 1D multi-plate heat transfer model based on temperature data of separator measured using thermograph in power generation process was developed to evaluate temperature of the reaction surface (T react). This study investigated the effect of T ini , flow rate and relative humidity of supply gas on T react distribution. The study finds that when using thin GDL, the even distribution of T react-T ini is obtained irrespective of thickness of PEM, T ini and relative humidity conditions. T react-T ini using Nafion 115 is higher than the other thin PEMs irrespective of T ini and relative humidity conditions. It can be concluded that the even temperature distribution could be achieved by using thin PEM and GDL.

Impact of Separator Thickness on Temperature Distribution in Single Polymer Electrolyte Fuel Cell Based on 1D Heat Transfer

“…W E indicates the electric work produced by PEFC. E i and W E are defined as following [24] [25] [26] [27]:…”

“…A few researchers [4] [22] [23] have reported numerical simulation on temperature distribution in a single PEFC which is operated at a higher temperature than usual. However, only a few papers [4] [22] have investigated the tempera-ture distribution on the interface between PEM and electrode at the cathode, which is defined as the reaction surface in this study, excluding the research conducted by the authors [24] [25] [26] [27]. The previous studies [24] [25] [26] [27] have confirmed the thickness effect of not only PEM but also GDL on the distribution of temperature at reaction surface (T react ) in a single PEFC at a higher temperature, i.e.…”

“…However, only a few papers [4] [22] have investigated the tempera-ture distribution on the interface between PEM and electrode at the cathode, which is defined as the reaction surface in this study, excluding the research conducted by the authors [24] [25] [26] [27]. The previous studies [24] [25] [26] [27] have confirmed the thickness effect of not only PEM but also GDL on the distribution of temperature at reaction surface (T react ) in a single PEFC at a higher temperature, i.e. 90˚C or 100˚C by the heat transfer model using the experimental temperature distribution data gotten by means of thermograph.…”

“…Using thinner PEM and thinner GDL at the same time is adopted for this analysis. The previous studies conducted by the authors [24] [25] [26] [27] have clarified using thinner PEM and thinner GDL at the same time is effective in order to obtain higher power generation performance of PEFC operated at higher temperature, i.e. 90˚C and 100˚C.…”

A Study on the Evaluation of Effective Properties of Randomly Distributed Gas Diffusion Layer (GDL) Tissues with Different Compression Ratios

“…Recently, in order to improve the efficiency of the flow characteristics inside the GDL, various studies have been carried out from the viewpoint of the design such as the clamping pressure that is produced in the stack assembly process, the assembling method and the optimum structural design method [7,8]. These studies aim to control the material characteristics and the design variables of fuel cells, such as hydrophobic polymer content [9,10], pore-size distribution [11,12], temperature distribution [13], humidity, differential pressure effects and compressive force effects of GDLs [14][15][16][17][18][19][20][21][22][23]. The amount of compression ratio of the GDL affects the porosity, directionality and the fraction of the pore space occupied by liquid water and affects the performance of a fuel cell.…”