TY - JOUR

T1 - Microstructure degradation of LSM-YSZ cathode in SOFCs operated at various conditions

AU - Liu,Yi-Lin

AU - Thydén,Karl Tor Sune

AU - Chen,Ming

AU - Hagen,Anke

PY - 2012

Y1 - 2012

N2 - Systematic microstructural analyses have been carried out on a series of technological SOFCs that went through long-term cell tests with various operating parameters including temperature, current load and time length under current. For the LSM-YSZ cathode, a number of microstructure degradation mechanisms have been identified. And it has been observed that different mechanisms dominate the degradation process under different test conditions. The severe cathode degradation at 750 °C operation with high current density is attributed to a loss of the cathode/electrolyte interface stability. For the cells tested at 850 °C, the interface stability is maintained due to further sintering during cell operation. A cell test lasting for 2 years (17500 h) at 850 °C with a moderate current density (not greater than 1 A/cm2) has shown that the cathode microstructure is fairly robust to the degradation processes at this temperature, such as grain coarsening and element diffusion. The cell degrades mildly with a cell voltage degradation rate of 7 mV/1000 h.

AB - Systematic microstructural analyses have been carried out on a series of technological SOFCs that went through long-term cell tests with various operating parameters including temperature, current load and time length under current. For the LSM-YSZ cathode, a number of microstructure degradation mechanisms have been identified. And it has been observed that different mechanisms dominate the degradation process under different test conditions. The severe cathode degradation at 750 °C operation with high current density is attributed to a loss of the cathode/electrolyte interface stability. For the cells tested at 850 °C, the interface stability is maintained due to further sintering during cell operation. A cell test lasting for 2 years (17500 h) at 850 °C with a moderate current density (not greater than 1 A/cm2) has shown that the cathode microstructure is fairly robust to the degradation processes at this temperature, such as grain coarsening and element diffusion. The cell degrades mildly with a cell voltage degradation rate of 7 mV/1000 h.

KW - Interface

KW - Solid Oxide Fuel Cells

KW - Degradation

KW - Long-term stability

KW - SEM

KW - LSM-YSZ cathode

KW - Microstructure

U2 - 10.1016/j.ssi.2011.10.020

DO - 10.1016/j.ssi.2011.10.020

M3 - Journal article

VL - 206

SP - 97

EP - 103

JO - Solid State Ionics

T2 - Solid State Ionics

JF - Solid State Ionics

SN - 0167-2738

ER -