Solid electrolyte materials Li1.3Al0.3Ti1.7(PO4)(3) (NASICON, R-3c) were synthesized via novel acetate routes A (simple precipitate), A1 (spray-dried precipitate) and B (sol-gel synthesis) and their properties are compared. Spray-dried spherical granules show characteristic features as a result of their particular microstructure. Temperature dependent DC measurements provide an informative basis to discuss two different grain boundary ionic conduction mechanisms in these spray-dried granules. (C) 2011 Elsevier B.V. All rights reserved.