Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells

Fuel cells (FCs) are among the more efficient solutions to limit the emission of greenhouse gases. Based on the conversion of the chemical energy of a fuel (often hydrogen) and an oxidizing agent (often oxygen) into electrical energy, a typical FC produces a voltage of 0.7 V under load. The potentia...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Giffin Jürgen, Conti Fosca, Korte Carsten
Formato:	article
Lenguaje:	EN
Publicado:	Sciendo 2021
Materias:	acid doping electrical conductivity fuel cell phosphoric acid polymer electrolyte membranes proton exchange membrane vapor activity Renewable energy sources TJ807-830
Acceso en línea:	https://doaj.org/article/d813692b8e6241d1a4ef49dcd4018465
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:d813692b8e6241d1a4ef49dcd4018465
record_format	dspace
spelling	oai:doaj.org-article:d813692b8e6241d1a4ef49dcd40184652021-12-05T14:11:10ZElectrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells2255-883710.2478/rtuect-2021-0034https://doaj.org/article/d813692b8e6241d1a4ef49dcd40184652021-01-01T00:00:00Zhttps://doi.org/10.2478/rtuect-2021-0034https://doaj.org/toc/2255-8837Fuel cells (FCs) are among the more efficient solutions to limit the emission of greenhouse gases. Based on the conversion of the chemical energy of a fuel (often hydrogen) and an oxidizing agent (often oxygen) into electrical energy, a typical FC produces a voltage of 0.7 V under load. The potential is highly increased by placing the cells in series to obtain a stacked cell. Among the types of FCs, the polymer electrolyte membrane FCs (PEMFCs) are developed mainly for transport applications, because of their low impact on the environment, high power density and light weight compared with other types of FCs. Phosphoric acid (H3PO4) doped polybenzimidazole (PBI) membranes are widely used as efficient electrolytes. The performance of a (high temperature, 130–200 °C) HT-PEMFC depends mainly on the amount of H3PO4 in the solid polymer membrane. The strong autoprotolysis of H3PO4 is responsible for the high proton conductivity also in the anhydrous state. In this study, the H2OH3PO4 system is investigated in the temperature range 60–150 °C with varying water vapour activity at constant atmospheric pressure. Main purpose is to gain more insights into the kinetics of the equilibria in the H2O-H3PO4 system, which influence the fuel cell performance. Density, water content, electrical conductivity and activation energy are determined by exposing H3PO4 solutions for sufficiently long periods to controlled gas atmosphere in order to reach near-equilibrium conditions. The coexistence of ortho- and pyrophosphoric acid is analysed and higher condensed species are also considered. A new setup fully made in quartz is designed and developed to mix the phosphoric acid solutions in a climate chamber. The experimental results are compared to literature data to validate the developed setup and the methodology.Giffin JürgenConti FoscaKorte CarstenSciendoarticleacid dopingelectrical conductivityfuel cellphosphoric acidpolymer electrolyte membranesproton exchange membranevapor activityRenewable energy sourcesTJ807-830ENEnvironmental and Climate Technologies, Vol 25, Iss 1, Pp 467-478 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	acid doping electrical conductivity fuel cell phosphoric acid polymer electrolyte membranes proton exchange membrane vapor activity Renewable energy sources TJ807-830
spellingShingle	acid doping electrical conductivity fuel cell phosphoric acid polymer electrolyte membranes proton exchange membrane vapor activity Renewable energy sources TJ807-830 Giffin Jürgen Conti Fosca Korte Carsten Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells
description	Fuel cells (FCs) are among the more efficient solutions to limit the emission of greenhouse gases. Based on the conversion of the chemical energy of a fuel (often hydrogen) and an oxidizing agent (often oxygen) into electrical energy, a typical FC produces a voltage of 0.7 V under load. The potential is highly increased by placing the cells in series to obtain a stacked cell. Among the types of FCs, the polymer electrolyte membrane FCs (PEMFCs) are developed mainly for transport applications, because of their low impact on the environment, high power density and light weight compared with other types of FCs. Phosphoric acid (H3PO4) doped polybenzimidazole (PBI) membranes are widely used as efficient electrolytes. The performance of a (high temperature, 130–200 °C) HT-PEMFC depends mainly on the amount of H3PO4 in the solid polymer membrane. The strong autoprotolysis of H3PO4 is responsible for the high proton conductivity also in the anhydrous state. In this study, the H2OH3PO4 system is investigated in the temperature range 60–150 °C with varying water vapour activity at constant atmospheric pressure. Main purpose is to gain more insights into the kinetics of the equilibria in the H2O-H3PO4 system, which influence the fuel cell performance. Density, water content, electrical conductivity and activation energy are determined by exposing H3PO4 solutions for sufficiently long periods to controlled gas atmosphere in order to reach near-equilibrium conditions. The coexistence of ortho- and pyrophosphoric acid is analysed and higher condensed species are also considered. A new setup fully made in quartz is designed and developed to mix the phosphoric acid solutions in a climate chamber. The experimental results are compared to literature data to validate the developed setup and the methodology.
format	article
author	Giffin Jürgen Conti Fosca Korte Carsten
author_facet	Giffin Jürgen Conti Fosca Korte Carsten
author_sort	Giffin Jürgen
title	Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells
title_short	Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells
title_full	Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells
title_fullStr	Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells
title_full_unstemmed	Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells
title_sort	electrical conductivity and water effects in phosphoric acid solutions for doping of membranes in polymer electrolyte fuel cells
publisher	Sciendo
publishDate	2021
url	https://doaj.org/article/d813692b8e6241d1a4ef49dcd4018465
work_keys_str_mv	AT giffinjurgen electricalconductivityandwatereffectsinphosphoricacidsolutionsfordopingofmembranesinpolymerelectrolytefuelcells AT contifosca electricalconductivityandwatereffectsinphosphoricacidsolutionsfordopingofmembranesinpolymerelectrolytefuelcells AT kortecarsten electricalconductivityandwatereffectsinphosphoricacidsolutionsfordopingofmembranesinpolymerelectrolytefuelcells
_version_	1718371327490916352

Electrical Conductivity and Water Effects in Phosphoric Acid Solutions for Doping of Membranes in Polymer Electrolyte Fuel Cells

Ejemplares similares