Assessment of the durability of low-cost Al bipolar plates for High Temperature PEM fuel cells

The present research aims to assess the durability of a single cell formed by a commercial high-temperature membrane electrode assembly (MEA) and Al bipolar plates (Al-BPPs) coated with Ni-P. To this end, an accelerated degradation test based on voltage load cycles is carried out, and the effects of...

ver descrição completa

Detalhes bibliográficos
Autores: Alegre Gresa, Cinthia, Álvarez Manuel, Laura, Mustata, Radu, Valiño García, Luis, Lozano Fantoba, Antonio, Barreras Toledo, Félix
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2019
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:dnet:digitalcsic_::7e99be4c2d017ae7ce92bd1240a41195
Acesso em linha:http://hdl.handle.net/10261/209571
Access Level:acceso abierto
Palavra-chave:High temperature PEM fuel cell
Aluminum bipolar plates
Ni-P coating
MEA degradation
Stress test
Descrição
Resumo:The present research aims to assess the durability of a single cell formed by a commercial high-temperature membrane electrode assembly (MEA) and Al bipolar plates (Al-BPPs) coated with Ni-P. To this end, an accelerated degradation test based on voltage load cycles is carried out, and the effects of the degradation on the MEA and its impact on the Al-coated bipolar plates are analyzed. They are compared with the results obtained testing a similar cell formed by the same MEA with graphite plates. MEAs from both cells were analyzed by different characterization techniques before and after the degradation tests (XRD, SEM, TEM). The performance of the Al-based cell is initially better, but it suffers a faster deterioration mainly due to the degradation of the Ni-P surface coating. A green deposit is formed, probably due to the chemical reaction of the phosphoric acid leached from the MEA. These deposits cause an increase in the contact resistance of the plates, local channel blockages and, eventually, a larger degradation. This work proves that PBI membranes still need to be improved to ensure their long-term durability.