Improved operation of SO₂ depolarized electrolyser stack for H₂ production at ambient conditions

In this paper, the performance of a robust SO₂ depolarized electrolyser (SDE) stack that involves neither Pt catalyst nor carbon compounds at ambient conditions is demonstrated. In particular, the effect of different anolyte flow configurations to the overall H₂ production rate and SO₂ carry-over phenomenon is presented. These results indicate that serpentine anolyte flow (U-configuration) provides higher SO₂ conversion, however, results in a more severe SO₂ carry-over phenomenon due to increased membrane-electrolyte interface. In addition, individual unit cells in the stacks are monitored for further understanding about the different operational environment in each cell and to provide guidelines for future SDE stack design.