Zr- and Ce-doped Li(6)Y(BO(3))(3) electrolyte for all-solid-state lithium-ion battery

The ionic conductivity of Li(6)Y(BO(3))(3) (LYBO) was enhanced by the substitution of tetravalent ions (Zr(4+) and Ce(4+)) for Y(3+) sites through the formation of vacancies at the Li sites, an increase in compact densification, and an increase in the Li(+)-ion conduction pathways in the LYBO phase. As a result, the ionic conductivity of Li(5.875)Y(0.875)Zr(0.1)Ce(0.025)(BO(3))(3) (ZC-LYBO) reached 1.7 × 10(−5) S cm(−1) at 27 °C, which was about 5 orders of magnitude higher than that of undoped Li(6)Y(BO(3))(3). ZC-LYBO possessed a large electrochemical window and was thermally stable after cosintering with a LiNi(1/3)Mn(1/3)Co(1/3)O(2) (NMC) positive electrode. These characteristics facilitated good reversible capacities in all-solid-state batteries for both NMC positive electrodes and graphite negative electrodes via a simple cosintering process.