Fabrication and Demonstration of 1 kW Class SOFC Stack and System for Residential Power Generation Application

摘要

The planar type 1 kW class solid oxide fuel cell (SOFC) stack using metallic interconnectsnsuch as ferritic stainless steel has been developed for application in a residentialnpower generation system. For the intermediate temperature operation of the SOFC, anhigher performance of anode-supported single cells of 10u000110 cm2 with a thin electrolytenlayer of yttria-stabilized zirconia were fabricated by slurry coating, and their performancesnwere improved by a microstructure-controlled anode substrate and by introducingnalternative cathode materials. The thicknesses of the electrolyte and the cathodenlayers were about 20 u0002m and 40 u0002m, respectively. I-V and ac impedance characteristicsnof single cells were evaluated at an intermediate temperature u0001650–800°Cu0002 by usingnhydrogen gas as fuel. The maximum power density of the 10u000110 cm2 anode-supportedncells was about 0.32 W/cm2 at 750°C and 0.2 W/cm2 at 650°C. In this work a 1 kWnclass SOFC stack composed of 37 cells u000110u000110 cm2u0002 was successfully manufacturednand a SOFC system with balance of plant (BOP) (reformer, heat exchanger, catalyticnburner, etc.) integrated for combined heat and power. The system designed for powerngeneration by using a natural gas as fuel can concurrently produce electricity at a SOFCnstack and hot water from recuperating heat. The system showed a maximum dc output ofn1.3 kWe. Detailed status and experimental results of the 1 kW SOFC system will bendiscussed in this paper.