Investigation of water generation and accumulation in polymer electrolyte fuel cells using hydro-electrochemical impedance imaging

JOURNAL OF POWER SOURCES

卷:414

Article

Wu, Y.¹  Meyer, Q.²  Liu, F.³  Rasha, L.¹  Cho, J. I. S.¹  Neviile, T. P.¹  Millichamp, J.¹  Ziesche, R.¹  Kardjilov, N.⁴  Boillat, P.⁵  Markoetter, H.⁴  Manke, I.⁴  Cochet, M.⁵  Shearin, P.¹  Brett, D. J. L.¹ 

[1] UCL, Dept Chem Engn, Electrochem Innovat Lab, London WC1E 7JE, England

[2] UNSW, Sch Chem, Nanoelectrochem Grp, Sydney, NSW 2052, Australia

[3] UCL, Dept Elect & Elect Engn, London WC1E 7JE, England

[4] HZB, Hahn Meitner Pl 1, D-14109 Berlin, Germany

[5] PSI, NIAG, CH-5232 Villigen, Switzerland

关键词: Neutron imaging;    Polymer electrolyte fuel cell;    Water management;    Electro-hydrography;   

DOI  :  10.1016/j.jpowsour.2019.01.003

来源: Elsevier

【 摘 要 】

In-depth understanding of water management is essential for the optimization of the performance and durability of polymer electrolyte fuel cells (PEFCs). Neutron imaging of liquid water has proven to be a powerful diagnostic technique, but it cannot distinguish between 'legacy' water that has accumulated in the system over time and 'nascent' water recently generated by reaction. Here, a novel technique is introduced to investigate the spatially resolved water exchange characteristics inside PEFCs. Hydro-electrochemical impedance imaging (HECII) involves making a small AC-sinusoidal perturbation to a cell and measuring the consequential water generated, using neutron radiographs, associated with the stimulus frequency. Subsequently, a least-squares estimation (LSE) analysis is applied to derive the spatial amplitude ratio and phase shift. This technique provides a complementary view to conventional neutron imaging and provides information on the source and 'history' of water in the system. By selecting a suitable perturbation frequency, HECII can be used to achieve an alternative image 'contrast' and identify different features involved in the water dynamics of operational fuel cells.

【 授权许可】

Free