It was recalled that the ionic conduction mechanism in high-temperature sulfate phases had been extensively studied, and that 2 mechanisms (paddle-wheel, percolation) had been proposed for ionic migration. The Zn2+ ion was selected here as a dopant for Li2SO4, and the transport mechanism was investigated via conductivity changes. The results showed that the conductivities of all of the Zn2+-containing samples were higher than that of β-Li2SO4(Al2O3) below 500C. Above 550C, the samples exhibited higher conductivities than that of α-Li2SO4. However, the conductivity first decreased when the Zn2+ content was less than 4mol%, and then increased to a maximum at about 7mol%Zn2+ or 7mol% of ionic vacancies. It was concluded that both the paddle-wheel and percolation mechanisms contributed to ionic conduction in α-Li2SO4.

Electrical Conductivity in Zn2+-Substituted Lithium Sulfate-Alumina Ceramics. G.Meng, S.Tao, D.Peng: Solid State Ionics, 2000, 136-137, 495-9