Practical deployment of anion exchange membrane water electrolyzers (AEMWEs) requires a comprehensive understanding of the influence of key parameters and components such as porous transport layer (PTL) structure, interlayer material and architecture, applied compression pressure, and electrolyte management on the performance and durability under realistic operating conditions. Herein, these parameters were comprehensively investigated in a flow-field free single-cell under “dry-cathode” configuration with an external applied external pressure of 10 and 20 bar. Multiple interlayers and PTL were evaluated with the objective of optimizing the contact resistance and pressure distribution over the membrane electrode assembly while enhancing the chemical stability. A wire-sintered nickel interlayer combined with Ni mesh was identified as the optimal configuration, outperforming the stability of the stainless-steel-based counterparts that exhibited an accelerated performance degradation after a 30-hour period operating at 1 A cm -2 . Flow-rate studies show that electrochemical performance of the AEMWE was largely independent of anode KOH circulation rate when this was above 3.0 mL min -1 cm -2 , whereas insufficient flow (1.5 mL min -1 cm -2 ) led to pronounced performance losses, particularly at high current densities. Long-term stability tests exceeding 400 h on a ∼7 cm 2 AEMWE single cell demonstrated a strong dependence on electrolyte concentration and operating current density, with degradation rates decreasing from 1.260 mV h -1 in 0.1 M KOH to 0.175 mV.h -1 in 1 M KOH at 0.5 A cm -2 , and increasing to 0.949 mV h -1 at 1.0 A cm -2 . Post-operation analysis revealed negligible Ni dissolution and just a small Fe leaching detected from the anode catalyst. Overall, this study provides practical design guidelines for AEMWE operation under industrially relevant conditions.
Moulaee et al. (Fri,) studied this question.