Material design of new lithium ionic conductor, thio-LISICON, in the Li2S–P2S5 system

Preparation of lithium ion conducting glasses and glass–ceramics for all-solid-state batteries

“…The XRD pattern of the glass-ceramic after crystallization (q) (except for the peaks due to Li 2 S crystal () which remains a little in the as-prepared glass) is very similar to that of the thio-LISICON Li 4Àx Ge 1Àx P x S 4 phase in region II (0.6 < x < 0.8) (abbreviated name: thio-LIS-ICON II), which exhibited high conductivity of 2.2 Â 10 À3 S cm À1 at room temperature [25]. Thio-LIS-ICON Li 3+5x P 1Àx S 4 without germanium has also been synthesized by solid-state reaction [26]. This thio-LISICON phase is reported to have the different structure from the thio-LISICON II and exhibit lower conductivity of 1.5 Â 10 À4 S cm À1 than the thio-LISICON II and the glass-ceramics.…”

“…This thio-LISICON phase is reported to have the different structure from the thio-LISICON II and exhibit lower conductivity of 1.5 Â 10 À4 S cm À1 than the thio-LISICON II and the glass-ceramics. The crystal phases with the same structure as the thio-LISICON II were not formed by solid-state reaction in the Li 2 S-P 2 S 5 binary system [26], suggesting that the thio-LISICON II analog would be precipitated as a metastable phase from the mechanically milled glass. We confirmed that the thio-LISICON II analog was formed in the Li-rich 80Li 2 S Á 20P 2 S 5 glass while it could not be formed in the 75Li 2 S Á 25P 2 S 5 glass; in the latter case, the conductivity enhancement by crystallization was slightly observed [22].…”

Alkali Metal Cation and Proton Conductors: Relationships between Composition, Crystal Structure, and Properties

“…First principles modeling of the Li þ diffusion in g-Li 3 PO 4 [236] predicts a considerable anisotropy, but the single-crystal conductivity of the g-type Li 3.34 P 0.66 Ge 0.34 O 4 has been found almost isotropic [237]. Thio-LISICONS, Li 4Àx Ge 1Àx P x S 4 [238], Li 4À2x Zn x GeS 4 , Li 4 þ x þ y Ge 1Àx-z Ga x S 4 [239], Li 4 þ x Si 1Àx Al x S 4 , Li 4Àx Si 1Àx P x S 4 [240], and Li 4 þ 5x Si 1Àx S 4 [241], are similar to their oxo-counterparts, but often show complicated superstructures and/or slight monoclinic distortions. The larger and more polarizable S 2À ions provide a higher Li þ ion conductivity, especially at low temperatures.…”

Thermal Stability of Various Cathode Materials against Li_6.25Al_0.25La₃Zr₂O₁₂ Electrolyte

“…There are many kinds of inorganic solid electrolytes such as sulfidetype electrolytes (ex. Li 2 S-P 2 S 5 glass ceramics 1 and thio-LISICONtype 2,3 ) and oxide type electrolytes (NASICON-type, 4 perovskitetype 5 and garnet-type 6,7 etc.). Among many kinds of inorganic electrolytes, garnet structure oxide materials such as Li 7 have advantages, such as high Li + conductivity (10 ¹4 S cm…”