Stack of solid oxide fuel cells

Abstract

Purpose – The paper aims to present the innovative design of a planar multilayered high temperature solid oxide fuel cell (SOFC), which is easy to manufacture, and features high resistance to rapid temperature changes. Temperature resistance was accomplished thanks to easy to heat, thin flat ceramic structure of the cell and elimination of metallic interconnections. Design/methodology/approach – The ceramic fuel cell consists of the anode core made of six to eight layers of nickel/yttria-stabilized zirconia tapes (Ni/YSZ) isostatically pressed into a laminate. Two networks of fuel distribution microchannels are engraved on both sides of the anode laminate. The microchannels are subsequently covered with a thin layer of the functional anode tape made of Ni/YSZ and a solid electrolyte tape made of YSZ. Findings – The single planar double-sided ceramic SOFC of dimensions 19 × 60 × 1.2 mm3 provides 3.2 Watts of electric power. The prototype of the battery which consists of four SOFCs provides an output power of > 12 W. Tests show that the stack is resistant to the rapid temperature change. If inserted into a chamber preheated to 800°C, the stack provides the full power within 5 minutes. Multiple cycling does not destroy the stack. Originality/value – This anode-supported fuel cell structure is provided with thin anode functional layers suspended on a large number of fine beams. The whole anode structure is made with the same ceramic material, so the mechanical stress is minimized during the cell operation.