tailieunhanh - Lithium-ion Batteries Part 7

Tham khảo tài liệu 'lithium-ion batteries part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | A novel all-solid-state thin-film-type lithium-ion battery with in-situ prepared electrode active materials 77 date. Figure 1 shows the temperature dependence of ionic conductivities for these conductors. Several kinds of conductors such as Li-PAl2O3 Yao and Kummer 1967 and Li3N Rabenau A. 1982 show high ionic conductivities larger than 10-3 S cm-1 even at room temperature comparable to that of the currently used liquid or gel electrolytes in lithium-ion batteries. However they are not simply used as solid electrolytes for lithium batteries because of their chemical instability. For example Li3N has a low decomposition potential V vs Li Li so that its application to all-solid-state batteries is limited. t C Fig. 1. a Temperature dependence of ionic conductivities for typical solid state lithium-ion conductors listed in Table 1. Dotted box in panel a is enlarged in panel b . Crystalline oxide-based inorganic solid electrolytes with higher chemical stability have been explored since the late 1970s. The material design of crystalline oxide-based ionic conductors is based on certain structural criteria i mobile ions should have suitable sizes for conduction pathways in the lattice and ii there should be disorder in the mobile ion sublattice. Based on these considerations solid solutions of Li4GeO4-Li3VO4 which is isostructural to Li14Zn GeO4 4 lithium super ionic conductor LISICON Hong 1978 related to the Ỵ-LÍ3PO4 structure were synthesized Kuwano and West 1980 . Partial substitution of Li4GeO4 by Li3VO4 induced vacancies in the lithium sites resulting in easier lithium-ion hopping in the structure. The substituted crystal attained ionic conductivity of 4 X 10-5 S cm-1 at room temperature which were a few orders higher than those of the members. Another example is lithium lanthanum titanate Li3xLa 2 3 -xTiO3 x LLT with ABO3-perovskite structure Inaguma et al. 1993 . LLT showed high ionic conductivity on the order of 10-3 S cm-1 taking .