High-Performance La<sub>0.9</sub>Sr<sub>0.1</sub>Ga<sub>0.8</sub>Mg<sub>0.2</sub>O<sub>3-δ</sub> Electrolyte-Based Direct Raw Brown Coal Fuel Cells
Xiao Chen, Can Wu, Senran Hao, Boyuan Liu, Tengda Lu, Peng Dong, Yingjie Zhang, Jie Xiao, Xiaoyuan Zeng, Shuo Zhai
Abstract
The direct carbon solid oxide fuel cell (DC-SOFC) is a potential energy conversion device that cleanly and effectively utilizes various carbon resources to generate electric power through electrochemical conversion. Recently, DC-SOFCs utilizing real-world coal fuel have gained great momentum due to the “dual carbon strategic goals”. Here, we report high-performance La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3-δ (LSGM) electrolyte-supported DC-SOFCs, by integrating Ag–Gd 0.1 Ce 0.9 O 2−δ (GDC) as symmetrical electrodes, which enable highly efficient utilization of raw brown coal as fuel. As a comparison, the performances of the conventional yttria-stabilized zirconia (YSZ) electrolyte supported-DC-SOFCs are also investigated. Fueled by raw brown coal, the LSGM-based cells can deliver a maximum power density of 367 mW cm –2 at 850 °C, which is distinctly superior than that of the YSZ-based cells (249 mW cm –2 ). In addition, stability tests reveal that under a discharge current of 0.15 A, the cell can achieve a discharge time of 4.38 h and a better fuel utilization of 14.8%, indicating that a large current discharge is more propitious for the LSGM-based DC-SOFCs fueled by raw brown coal to achieve higher fuel utilization. This study exhibits the enormous potential of LSGM as an electrolyte material for high-performance direct brown coal fuel cells and provides direction guidance for the optimization of discharge operation of DC-SOFCs directly utilizing brown coal in consideration of fuel utilization.