Enhancing ceramic fuel cells stability via anode lithium content regulation based on anode-assisted in-situ densification of electrolyte technology

The high temperature (>750 °C) operation has always hindered ceramic fuel cells (CFCs) commercialization. This work investigates the effect of lithium content in anode on the performance and stability of low-temperature (< 550 °C) CFCs based on anode-assisted in-situ densification of electrolyte (AASDE) technology. Electrochemical impedance spectroscopy (EIS) analysis reveals that increasing lithium content in the anode results in valley values for ohmic resistance and anode activation resistance while cathode activation resistance decreases. Consequently, CFCs with optimal lithium content in anode exhibit improved performance and stability. Specifically, CFCs using Li_0.8Ni_0.91Co_0.06Al_0.03O₂ anode achieve maximum power density of 493 mW cm⁻² and stable operation for 47 h at current density of 163 mA cm⁻² at 500 °C. EIS curves under various atmospheres and concentration cell curve indicate that sodium doped samarium oxide (NDS) electrolyte shows proton conduction based on AASDE technology. High temperature contact angle of 2.6 ° indicates that LiOH can adsorb onto NDS, forming a stable physicochemical system. Based on a stable electrolyte system, the CFCs maintain stable operation for 42 h at 450 °C. This study highlights the potential for low-cost, stable operation of CFCs at low temperatures based on AASDE technology.