Hybrid Direct Carbon Fuel Cells with Different Types of Mineral Coal

Abstract

Three types of coal, anthracite, bituminous and lignite with no pretreatment, were investigated in hybrid direct carbon fuel cells (HDCFC). The HDCFC is composed of 1 mm YSZ electrolyte-supported cell with a NiO-YSZ anode and a LSM-YSZ cathode, and lithium-potassium carbonate mixed with coal in the anode chamber. Anthracite and bituminous coals show promising performance. Bituminous coal shows good initial cell performance as well as short term durability in two hour tests; whilst anthracite coal shows good initial cell performance but a slightly faster performance drop as compared to bituminous coal. It seems that coal with high carbon content and low sulphur content is desirable for direct carbon fuel cell application. Gas analysis shows that the ratio of carbon to oxygen content in coal, is likely to be of importance for the cell performance in terms of carbon oxidation process.

Hybrid direct carbon fuel cell anode processes investigated using a 3-electrode half-cell setup

“…As shown in Table 2, de-mineralized anthracite samples (AIII-MD, AIII-C) exhibited poor performance (low current at fixed overpotential) at 800 C in 96e4 N 2 eCO 2 , with bituminous coal showing the highest performance, as has been reported elsewhere [3,6,41,42].…”

“…The use of anthracite coal-based fuels have previously been shown to give relatively limited performance in SOFC-type [3], MCFC-type DCFC [6,11] and HDCFC configurations [3,41,42]. Although, anthracite has been reported to generate lower Step A is the dissolution of CO 2 into the molten carbonate solution, Step B is dissolved CO 2 transport to the solid carbon particle, Step F is the dissolved CO transport between carbon particle and Ni-YSZ interface, and Step I is the dissociation of electrochemically formed CO 2 into the under-saturated molten carbonate solution.…”

Application of Ternary Carbonate in Hybrid Direct Coal Fuel Cells

“…The electrochemical test system is shown in previous paper (11). A YSZ electrolyte in 1 mm thickness was prepared by a dry-pressing method.…”

Comparative study of durability of hybrid direct carbon fuel cells with anthracite coal and bituminous coal

“…Lignite coal, bituminous coal and anthracite coal were evaluated in a button cell with a NiO-YSZ anode, a YSZ electrolyte and a LSM-YSZ cathode. The bituminous and anthracite coal had shown good durability over two hours of testing compared to the lignite coal 15 . We also investigated the application of ternary carbonate of lithium, sodium and potassium carbonate with a molar ratio of 43.5:31.5:25 in HDCFCs.…”

“…The fast degradation rate with raw coal was attributed to its ash accumulation on the anode surface, and also to the continuous carbon consumption 14 . In our previous research, different types of coal were selected for a primary test in hybrid DCFCs 3,15,16 . Lignite coal, bituminous coal and anthracite coal were evaluated in a button cell with a NiO-YSZ anode, a YSZ electrolyte and a LSM-YSZ cathode.…”