Wanbing Guan

Research on Performance of LSM Coating on Interconnect Materials for SOFCs

Experiments were conducted using SUS430 and Crofer 22 APU steels coated by LSM using plasma spray and slurry spray methods, respectively. High-temperature conductivity and oxidation resistance were investigated. For comparison, SUS430 and Crofer 22 APU without LSM coating were also investigated and coefficient of thermal expansion (CTE) was measured. The results show that the materials without LSM coating exhibit almost the same CTE as YSZ electrolyte in a range of temperatures of 550~850℃. When coated with LSM, the oxidation rate of the steels decreases by 30~40% using slurry spray and by 10~30% using plasma spray whereas the steels using plasma spray have a better high-temperature conductivity than the steels using slurry spray. It is thus concluded that the LSM coating has a limited effect on increasing high-temperature conductivity while it can effectively reduce the oxidation of the steels.

Solid Oxide Fuel Cell Development at NIMTE

The largest SOFC R&D activity in China is conducted at NIMTE where 45 full time staff is vertically integrated. We manufacture and sell planar anode supported cells for international market with the highest performance/price ratio. We offer various nanopowders including LSM, LSCF, LSC, CGO, YSZ and SSZ. Long term tests on performance degradation, in particular at low temperature and high current density, are intensively carried out in our cell testing group. We demonstrated low cost stack by combining internal manifolding design and low cost components selection. A five cell short stack has run for more than 3000 hours and the voltage is monitored for individual cells. Stacks of 500 W to kW power range are built and tested. We successfully manufactured 30×30cm 2 cells for multi-kilowatt single stack. 2 kW power and heat co-generation system are under development and 20 kW electrical generation system is planned this year in collaboration with a large Chinese electricity generation company.

development and performance of planar sofc stacks

Stacks are made of conventional single cells with configuration of Ni-YSZ/YSZ/LSM-YSZ. Thermal cycling, degradation and power density are investigated. A cell stack unit showed degradation rate of less than 1%/per cycle and maintained 1.15 volt OCV after going through 1350 hours and 46 thermal cycles at 0.1 A/cm2 and 75O°C The OCV of two-cell stack was above 2.2 V after 400 hours and 15 thermal cycles at 0.1 Acm-2. The degradation of two cell stack was also lower than 1% per cycle. A five cell stack has been tested for more than 3000 hours in which the individual stack unit is monitored. Our 10 cell stack reached 310 W with 0.31 W/cm2 in power density. The single cell could reach 50 W power in the current stack design which corresponds to our results from single cell test with active area of 4x4 cm2. A stack of 550 W was built and tested. ©The Electrochemical Society.