Structural and crystallographical factors of sintered and non-sintered units of garnet type cubic Li7La3Zr2O12 (c–LLZO) on the Li-ion conductivity were examined by using c–LLZO nanostructured particles synthesized via a solid state route. Two structural unit genres used are (i) sintered pellets, and (ii) thick films. Preparative variations chosen were among others, sintering temperature for (i) and degree of dispersion and formulation of binders for (ii). For the interpretation of electric conductivity acquired from impedance spectra, we used the analytical tools X-ray diffractometry, Raman spectra, dynamic light scattering, electron microscopy and 6Li MAS NMR spectroscopy. By devising the preparative method, we succeeded in reaching the conductivity 8 x 10-5 S/cm for the sinterless thick film, which is about a half of the value from the sintered pellet. Out of diversity of controlling parameters for the conductivity, we preferentially discuss the grain structure and the interaction between the c-LLZO particles and binders in view of minimizing the contact resistance.