Abstract

Recently, eco-friendly sources of energy by fuel cells that use hydrogen as an energy source has emerged as the next generation of energy to solve the problem of environmental issues and exhaustion of energy. A solid oxide fuel cell (SOFC) classified based on the type of ion transfer mediator electrolyte has actively being researched. SOFC has several advantages over any other fuel cell because it’s unnecessary complex external reforming, and not used platinum catalyst that operating high temperature.
However, the reliability according to the thermal cycle is low during the operation of the fuel cell, and deformation problem comes from the difference in thermal expansion coefficient between the electrode material, the components made of ceramic material is also brittle, which means disadvantages in terms of the strength.
Therefore, in this study, considering the states of the manufacturing and stack and operating of SOFC single cells, the stress analyses in the each of the interfacial layer between the anode , electrolyte and the cathode were performed to get the basic data for reliability assessment of SOFC.
The obtained results are follows below von Mises stress inside the active area on a distance of 1 ㎛ from the electrode interface were estimated. The maximum stress of 1.66GPa were occurred at 1 ㎛ from anode-electrolyte interface to the electrolyte at the manufacturing stage. And also the principal strain according to the thickness direction at the manufacturing state was maximum in the electrolyte layer. The results in the case of stack stage are also estimation with the case of manufacture. And the stress inside the active area on a distance of 1 ㎛ from the electrolyte was obtained as maximum stress. The maximum strain was 0.00295 at 1 ㎛ from cathode at the operating stage. while the principal strain according to the thickness direction at the operating state was maximum in the cathode layer.
Futhermore the evaluation was done for the variation of the stress according to the stage of the operation divided into three stages of manufacturing, stack, and operating.