Study on Electro-Thermal Balance in Hydrogen Production via Pulse Electrolysis Using Reversible Solid Oxide Cells

Abstract: [Background]:Reversible Solid Oxide Cells (RSOC) represent a high-efficiency energy conversion technology suitable for large-scale storage of intermittent renewable energy. [Purpose]:However, RSOC stacks operating in high-temperature environments between 700℃ and 900℃ tend to generate significant internal temperature gradients, causing thermal stress and performance degradation. To address this, this study proposes a dynamic operation mode based on long-pulse periodic electrolysis to reduce temperature gradients in RSOC stacks. [Methods]:We used the COMSOL software to establish a planar RSOC multi-physics coupled model and analyze the effects of different pulse sequences on system temperature, temperature gradients, and hydrogen production rates. [Results]:Results show that dynamic operation stabilizes system temperature and significantly reduces temperature gradients. At voltages of 1.2V, 1.3V, and 1.4V, temperature gradients decreased by 43%, 44%, and 46% respectively. While pulsed electrolysis reduces hydrogen production rates, the loss remains minimal at lower voltages, with less than 7% loss at 1.2V.