“…Since the first study on primary solid-state Li-ion batteries in 1972 (Scrosati, 1972), large number of inorganic solid-state electrolytes were investigated for Li-S cells as well as Li-ion batteries, including LiSICON-type phosphates, perovskite-type La (2/3)x Li 3x TiO 3 (LLT), Li 3 N, and Li 4 SiO 4 (Hayashi et al, 2003b;Stramare et al, 2003;Kobayashi et al, 2008;Nagao et al, 2011Nagao et al, , 2013. A list of non-polymer electrolytes, comparing with other electrolytes including polymer electrolytes, ionic liquids, and gel electrolytes, are shown in Figure 6.…”