Structural and electrochemical properties of interconnect integrated solid oxide fuel cell

•An II-SOFC using alloy foam and high temperature sinter-joining method was fabricated.•Adoption of alloy foam can lead to significant improvement of gas transport and light weight.•A maximum power density of 0.37 W cm−2 was obtained at 800 °C.

Interconnect integrated solid oxide fuel cells (II-SOFC) have remaining design and process issues due to their differences in thermal and mechanical properties between metal and non-metal materials. In this work, a lightweight design of an II-SOFC using metal foam and a high temperature sinter-joining process, which is one of the less expensive fabrication methods, is proposed for mobile and automotive applications, and the electrochemical performance is evaluated. 8 mol% of Y2O3 stabilized ZrO2 (8YSZ) is used as electrolyte and NiO/8YSZ as anode material. Ce0.9Gd0.1O1.9 (CGO91) and Ba0.5Sr0.5Co0.8Fe0.2O3−d (BSCF)/Sm0.2Ce0.8O1.9 (SDC) are used as the in-situ buffer layer and in-situ composite cathode, respectively; to avoid oxidation of the metal interconnect, no additional sintering process is employed. A very strong bonding property is achieved at the ceramic-metal interface; the cell has a maximum power density of 0.37 W cm−2 at 800 °C in hydrogen operating conditions.

Graphical abstractSEM images of alloy foam and fully sinter joined metal alloy foam-supported cell; (a) ally foam before sintering, (b) fully sinter-joined metal alloy foam-supported cell, (c) top view of bonded surface, (d) side view of bonded area between anode and foam.Figure optionsDownload full-size imageDownload as PowerPoint slide