Electrical and Electrochemical Performances Evaluation of LaNi0.6Fe0.4O3 Cathode Contact and Current Collecting Layer in SOFCs

Abstract

In this work, the electrical and electrochemical performances of LaNi0.6Fe0.4O3 (LNF) cathode contact and current collecting layer are investigated. The screen-printed LNF thin film on LSCF-GDC cathode effectively improves the performance of anode supported single cell with maximum power density increase by ∼15% and polarization resistance decrement by ∼24%. However, the LNF layer is found to hinder oxygen diffusion under low cathode oxygen partial pressure below ∼0.07 atm. For the application as thick contact layer, an optimized method is developed in combination with alternate ink deposition and drying processes, to provide decent structural stability and interfacial contact. The area specific resistance (ASR) of thick LNF contact layer shows high long-term stability under current load of 300 mA cm−2. The ASR stabilizes at 0.086 Ω·cm2 for more than 1600 h. Moreover, the LNF contact layer operates stably after 7 thermal cycles. The results indicate that, LNF is promisingly applicable as current contact and collecting material in solid oxide fuel cells.