Wetting of Na on β″-Al2O3/YSZ composites was investigated using the sessile drop technique. The effects of moisture and surface preparation were studied at low temperatures. Electrical conductivity of Na/β″-Al2O3-YSZ/Na cells was also investigated at low temperatures and correlated to the wetting behavior. The use of planar β″-Al2O3 substrates at low temperature with low cost polymeric seals is realized due to improved wetting at low temperature and conductivity values consistent with the literature.