Improved mechanical strength, proton conductivity and power density in an ‘all-protonic’ ceramic fuel cell at intermediate temperature

Abstract

Protonic ceramic fuel cells (PCFCs) have become the most efficient, clean and cost-effective electrochemical energy conversion devices in recent years. While significant progress has been made in developing proton conducting electrolyte materials, mechanical strength and durability still need to be improved for efficient applications. We report that adding 5 mol% Zn to the Y-doped barium cerate-zirconate perovskite electrolyte material can significantly improve the sintering properties, mechanical strength, durability and performance. Using same proton conducting material in anodes, electrolytes and cathodes to make a strong structural backbone shows clear advantages in mechanical strength over other arrangements with different materials. Rietveld analysis of the X-ray and neutron diffraction data of BaCe0.7Zr0.1Y0.15Zn0.05O3−δ (BCZYZn05) revealed a pure orthorhombic structure belonging to the Pbnm space group. Structural and electrochemical analyses indicate highly dense and high proton conductivity at intermediate temperature (400–700 °C). The anode-supported single cell, NiO-BCZYZn05|BCZYZn05|BSCF-BCZYZn05, demonstrates a peak power density of 872 mW cm−2 at 700 °C which is one of the highest power density in an all-protonic solid oxide fuel cell. This observation represents an important step towards commercially viable SOFC technology.

A review of progress in proton ceramic electrochemical cells: material and structural design, coupled with value-added chemical production

“…11,233 Moreover, the fuel electrodes are often adopted as supports, which need to have sufficient mechanical strength and shock tolerance to prevent cell failure during operation. 275,276 Meanwhile, maintaining a reasonable porosity is essential to achieve rapid diffusion and transport of gases or electrolysis products. 275,276 In this section, adhering to the framework established in the previous sections, the focus is placed on innovative materials and structural design tailored for the application of different fuel gases.…”

“…275,276 Meanwhile, maintaining a reasonable porosity is essential to achieve rapid diffusion and transport of gases or electrolysis products. 275,276 In this section, adhering to the framework established in the previous sections, the focus is placed on innovative materials and structural design tailored for the application of different fuel gases.…”

Super–protonic conductors for solid acid fuel cells (SAFCs): a review

“…Because of its promising advantages, SOFC is still a desirable prospective alternative today, as evidenced by the fact that this technology is being used in more and more applications today, particularly in the sectors of portable power production and transportation [79,80]. Noteworthy, SOFCs based on proton-conducting electrolytes are also referred to as protonic ceramic fuel cells (PCFCs) [81,82]. By adopting affordable manufacturing techniques, PCFCs have made it feasible to attain significantly greater cell power densities at lower working temperatures (400-600 • C), potentially resulting in lower stack costs than traditional SOFC technology [83].…”

Classification of Solid Oxide Fuel Cells

“…The overwhelming majority of studies of H-SOFC are carried out on cells having an anode supported construction, which allows obtaining the highest power [ 39 , 78 , 97 , 98 ]. Only a few works were performed on cells with a supporting electrolyte [ 99 ] and supporting metal [ 100 , 101 ].…”