Toward Understanding of Temperature Dependence of an Advanced Ceramic Fuel Cell with Ni_0.8Co_0.15Al_0.05LiO₂ as an Electrode

Abstract

Ceramic fuel cells with Gd0.1Ce0.9O1.95 (GDC) as an electrolyte and Ni0.8Co0.15Al0.05LiO2 (NCAL)-coated foam Ni as a symmetric electrode are prepared. The effect of initial reduction temperature of the NCAL anode on the performance of the cells is investigated. When the initial test temperatures of the three cells were 550, 500, and 450 °C, respectively, the maximum power densities of the three cells at 450 °C were 0.221, 0.125, and 0.02 W·cm–2, respectively. At 450 °C, the ionic conductivities of the electrolytes in the cells with three different initial reduction temperatures were 0.288 (550 °C), 0.165 (500 °C), and 0.011 S·cm–1 (450 °C), respectively. During the test, LiOH/Li2CO3 produced by H2 reduction of the NCAL anode diffuses into the GDC electrolyte, and the interface between LiOH/Li2CO3 and GDC becomes the main channel of ion conduction. The scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction results indicated that the amount and the diffusion rate of the LiOH/Li2CO3 mixture diffused into the GDC electrolyte increased with the increase of initial reduction temperature. The LiOH/Li2CO3 mixture entering into the electrolyte will directly affect the effective area or the length of the ion conduction channel formed by the LiOH/Li2CO3 mixture and GDC in the electrolyte, thus significantly affecting the electrochemical performance of the cells.

Semiconductor Heterostructure (SFT–SnO2) Electrolyte with Enhanced Ionic Conduction for Ceramic Fuel Cells

“…The cross-sectional image of the evaluated pellet after fuel cell performance is shown in Figure b, where the symmetrical electrodes Ni–NCAL and SFT–SnO 2 are appropriately sandwiched together. The electrodes seem to be porous, contributing to the higher catalytic activity of NCAL electrodes; also, according to previous reports, NCAL is an excellent electrode, as depicted in Figure c. , Figure d shows the Ni–NCAL electrodes, where Ni foam is well attached to NCAL, and the electrolyte layer seems dense, as confirmed in Figure e. Figure f shows the uniform distribution of particles at the microscale, where particles are adherent establishing an intelligent pathway for easy and quick charge transportation, which overall enhances the performance of the device.…”

Ni/NiO Exsolved Perovskite La0.2Sr0.7Ti0.9Ni0.1O3−δ for Semiconductor-Ionic Fuel Cells: Roles of Electrocatalytic Activity and Physical Junctions

“…The electrochemical performances of SIFCs with various semiconductor-ionic composite electrolytes were evaluated with the NCAL symmetric electrode under the same operating condition. In literature, NCAL has been demonstrated to show high activity toward fuel cell electrode ORR and HOR reactions. , As exhibited in Figure c, all SIFCs (Cell IV-VI) showed OCV values above 1.10 V, and P max of 431–650 mW cm –2 were obtained. In contrast with the lower power outputs of the corresponding SLFCs (Figure a), the addition of the NCAL electrode layers in SIFC dramatically enhances the OCV and the fuel cell performance.…”

Unveiling the role of lithium in cerium oxide based ceramic fuel cells employing lithium compounds as the anode

“…Small well distributed porous nano particle ceria can be clearly observed before the treatment, whereas it becomes sticky and something like glue covers on its surface after treatment. The glue has been reported to be lithium hydroxide, 31,32 which reduces the electronic conductivity and gas leakage issue for the NCAL based fuel cell in this initial stage. Therefore, it is conjected that lithium is transferred from the anode to the cathode after hydrogen treatment, contributing to some of improved electrochemical performance.…”