Investigation into polymer electrolyte membrane fuel cell characteristics using four-layer electrode catalyst

Abstract

The use of auxiliary power and the cost of using main power decrease when the reactive gas is applied at low humidity for the operation of polymer electrolyte membrane fuel cells. The electrolyte membrane and the three-phase boundary of the electrode need to be improved to maintain this low humidity. We carried out a study of the electrode catalyst at low humidity in order to improve the cathode catalyst. Carbon support with a catalyst and fluorocarbon resin were mixed and then were treated at the melting temperature of fluorocarbon resin to fabricate the cathode-electrode catalyst layer. The transmission electron microscopy images of this electrode catalyst revealed that the surfaces of the catalyst particle and the carbon support were partly coated with a thin film of melted fluorocarbon resin. Ionomer electrolyte material was added to this electrode catalyst, and an electrode catalyst with a four-layer structure was fabricated. The durability of this four-layer electrode catalyst being operated at low humidity ͑42% relative humidity on the anode and the cathode͒ was evaluated by using a cell that contained the catalyst. The results demonstrated that the rate of deterioration was smaller than that of a conventional three-layer electrode catalyst. In addition, the load change test to assess the durability of the cell ͑current range between 75 and 600 mA cm −2 ͒ produced good results.

High Proton Conductivity of Water Channels in a Highly Ordered Nanowire

“…Currently, we are investigating approaches to tackle the challenge of placing the nanocrystals in an ordered arrangement between the cathode and the anode of fuel cells before the nanowires can be practically used for fuel cell applications. Future work in this area also includes further improve- ment of the conductivity under low-humidity and hightemperature conditions, which is critical for practical applications of automotive fuel cells, [30,31] by growing the nanowires in porous membranes or by using other aromatic carboxylic acids or aromatic sulfonic acids to provide more free protons. Growing nanowires in ordered, porous membranes, such as anodized Al 2 O 3 , will not only secure the fast transportation of protons in the anticipated direction between a cathode and an anode, but also enhance the robustness of the nanowires.…”

High Proton Conductivity of Water Channels in a Highly Ordered Nanowire

“…Currently, we are investigating approaches to tackle the challenge of placing the nanocrystals in an ordered arrangement between the cathode and the anode of fuel cells before the nanowires can be practically used for fuel cell applications. Future work in this area also includes further improvement of the conductivity under low‐humidity and high‐temperature conditions, which is critical for practical applications of automotive fuel cells,30, 31 by growing the nanowires in porous membranes or by using other aromatic carboxylic acids or aromatic sulfonic acids to provide more free protons. Growing nanowires in ordered, porous membranes, such as anodized Al 2 O 3 , will not only secure the fast transportation of protons in the anticipated direction between a cathode and an anode, but also enhance the robustness of the nanowires.…”

Investigation into the gas diffusion electrodes of polymer electrolyte membrane fuel cell under long-term durability test

“…5 The operating electrode area was 25 cm 2 . The MEA was held between two graphite separators with parallel-flow serpentine gas channels.…”