An investigation was made of  H+-ion diffusion in LATP glass and their interactions with the glass surface using both experimental and modelling approaches. The results indicated that the apparent H+-related current observed in the initial cyclic voltammetry scan should be attributed to the adsorption of H+ ions on the LATP glass rather than the bulk diffusion of H+ ions. Furthermore, density functional theory calculations indicate that the H+-ion diffusion energy barrier (3.21 eV) was much higher than that for Li+ ions (0.79 eV) and Na+ ions (0.79 eV) in a NASICON-type LiTi2(PO4)3 material. As a result, H+-ion conductivity in LATP glass was negligible at room temperature. However, significant surface corrosion was found after the LATP glass in a strong alkaline electrolyte. Therefore, to prevent LATP glass from corrosion, appropriate electrolytes must be developed for long-term operation of LATP in aqueous Li-air batteries.

H+ Diffusion and Electrochemical Stability of Li1+x+yAlxTi2-xSiyP3-yO12 Glass in Aqueous Li/Air Battery Electrolytes. F.Ding, W.Xu, Y.Shao, X.Chen, Z.Wang, F.Gao, X.Liu, J.G.Zhang: Journal of Power Sources, 2012, 214, 292-7