Development of hydroxide ion conductors for intermediate-temperature alkaline fuel cells

2017 Fiscal Year Final Research Report

• Project/Area Number: 25288106
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Inorganic industrial materials
• Research Institution: Nagoya University
• Principal Investigator: Hibino Takashi 名古屋大学, 環境学研究科, 教授 (10238321)
• Co-Investigator(Renkei-kenkyūsha): NAGAO Masahiro 名古屋大学, 大学院環境学研究科, 講師 (40432223)
• Project Period (FY): 2013-04-01 – 2018-03-31
• Keywords: 水酸化物イオン導電体 / アルカリ形燃料電池 / 中温作動 / 金属空気バッテリー

Outline of Final Research Achievements

Anion exchange membranes are widely viewed as promising candidates for the electrolyte component; however, the operating temperature of these membranes has been limited to 80 °C. The U.S. Department of Energy has recommended development of fuel cells capable of operating at temperatures up to 120 °C to reduce the cost of fuel cell vehicles. Here, we report SnP2O7-based hydroxide ion conductors and an intermediate-temperature fuel cell with the optimized electrolyte component. Hydroxide ion exchange capability was introduced into the bulk of SnP2O7 by the partial substitution of Sn4+ cations with high valency cations, such as Sb5+, Nb5+, V5+, and Ta5+. Consequently, Sn0.92Sb0.08P2O7 exhibited the highest hydroxide ion conductivity of 0.04 S cm-1 at 200 °C. Furthermore, a H2/air fuel cell with this membrane generated a power density of 147 mW cm-2 at 200°C. Notably, this membrane could also be utilized as the electrolyte component for rechargeable aluminum-air batteries.

Free Research Field

環境・エネルギー物質