Development of composite bipolar plate for polymer electrolyte membrane fuel cell

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05091
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 26050:Material processing and microstructure control-related
• Research Institution: Iwate University
• Principal Investigator: Yashiro Hitoshi 岩手大学, 理工学部, 教授 (60174497)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: PEFC / セパレーター / アルミニウム / 腐食

Outline of Final Research Achievements

In order to reduce the weight of the bipolar plates for polymer electrolyte fuel cells, a composite bipolar plate consisting of a carbon channel forming material and a reaction gas isolation plate made of aluminum (Al) has been proposed. When Al was not surface-treated, the cell voltage was not high enough due to the contact resistance with the flow path forming material, but the cell was successfully operated for 1000 hours. After the operation, Al maintained its luster on the cathode side, but turned white on the anode side, and an oxide film with a thickness of 1 μm or more was formed. By comparison with the results of the corrosion test of Al in the simulated environment, this result was considered to indicate that condensed water was generated on the anode side. On the other hand, when Al plate was treated with TiN-SBR, the cell performance was comparable to that using a carbon bipolar plate.

Free Research Field

工学

Academic Significance and Societal Importance of the Research Achievements

燃料電池車を普及させるため、セパレーターの重量と価格を下げることが強く望まれている。アルミニウム(Al)は軽量で低価格なことから、セパレーター材料として期待されているが、ガス拡散層と直接接触する状態での使用は、耐食性の点で困難と考えられていた。本研究では、セパレーターを流路形成材と反応ガス隔離板とに分け、Alを隔離板に使うことを提案した。その結果Alに接触抵抗改善のために表面処理を行うことで、優れた発電性能が得られることを実証できた。また、Alを隔離板として使用して発電試験を行うことで、直接観察することが困難な、流路内における凝縮水発生の有無を間接的に評価できることも明らかとなった。