Using aluminum and Li₂CO₃ particles to reinforce the α-LiAlO₂ matrix for molten carbonate fuel cells

The electrolyte substrate (matrix) of a molten carbonate fuel cell (MCFC) provides both ionic conduction and gas sealing. During the starting-up and operating of MCFC stacks at 923 K, the matrix can experience mechanical stresses that can cause cracking. In particular, the pure α-LiAlO₂ that is generally used for the MCFC possesses poor mechanical strength. In this study, we employed Al and Li₂CO₃ particles as reinforcement materials to increase the mechanical strength of the α-LiAlO₂ matrix for its stable long-term operation. The mechanical strength of the matrix increased dramatically after adding Al particles into the pure matrix. Moreover, we operated a single cell for 2000 h after adding Li₂CO₃ particles into the Al-reinforced matrix to prevent a Li-ion shortage caused by a lithiated Al reaction in the matrix.