TY - JOUR
T1 - A solid polymer water electrolysis system utilizing natural circulation
AU - Kobayashi, Yoshinori
AU - Kosaka, Kenichiro
AU - Yamamoto, Takashi
AU - Tachikawa, Yuya
AU - Ito, Kohei
AU - Sasaki, Kazunari
N1 - Funding Information:
The authors would like to thank New Energy and Industrial Technology Development Organization (NEDO) for supporting this study. The authors also thank Dr Stephen M. Lyth and Ms. Ayumi Zaitsu at Kyushu University for their editorial support.
Publisher Copyright:
© 2014 Hydrogen Energy Publications, LLC.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2014/10/2
Y1 - 2014/10/2
N2 - Solid Polymer Water Electrolysis (SPWE) is a method to efficiently produce high-purity hydrogen gas using a polymer electrolyte membrane-based system. SPWE systems that utilize natural water circulation (resulting from a difference in buoyancy) are a promising technology, which need no additional circulation pump for water supply to the electrolysis cells, and generate no pressure difference between the hydrogen generation and oxygen generation chambers. However, despite not needing an accurate pressure control, gas bubbles formed and trapped within the cell stacks can inhibit heat convection, leading to hot-spot formation and consequent destructive degradation. Improving the reliability is therefore one of the most important technological issues in natural circulation SPWEs. In this study, hot-spot formation is studied both by numerical heat and flow analysis, and by experimental in-situ visualization. This leads to insights into the degradation mechanisms of SPWE stacks, and their possible solutions. An improved design for an SPWE cell stack is successfully fabricated, and reliable operation up to 5000 h is demonstrated.
AB - Solid Polymer Water Electrolysis (SPWE) is a method to efficiently produce high-purity hydrogen gas using a polymer electrolyte membrane-based system. SPWE systems that utilize natural water circulation (resulting from a difference in buoyancy) are a promising technology, which need no additional circulation pump for water supply to the electrolysis cells, and generate no pressure difference between the hydrogen generation and oxygen generation chambers. However, despite not needing an accurate pressure control, gas bubbles formed and trapped within the cell stacks can inhibit heat convection, leading to hot-spot formation and consequent destructive degradation. Improving the reliability is therefore one of the most important technological issues in natural circulation SPWEs. In this study, hot-spot formation is studied both by numerical heat and flow analysis, and by experimental in-situ visualization. This leads to insights into the degradation mechanisms of SPWE stacks, and their possible solutions. An improved design for an SPWE cell stack is successfully fabricated, and reliable operation up to 5000 h is demonstrated.
UR - http://www.scopus.com/inward/record.url?scp=84908020914&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84908020914&partnerID=8YFLogxK
U2 - 10.1016/j.ijhydene.2014.07.153
DO - 10.1016/j.ijhydene.2014.07.153
M3 - Article
AN - SCOPUS:84908020914
SN - 0360-3199
VL - 39
SP - 16263
EP - 16274
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
IS - 29
ER -
