All-ceramic Li batteries based on garnet structured Li7La3Zr2O12

All-ceramic Li batteries (CLBs) are expected as next generation energy storage devices because of their potential to have higher energy density and safety than nowadays Li-ion batteries. Garnet structured Li7La3Zr2O12 (LLZO) plays an important role on CLB developments due to its fast Li-ion conductivity, intrinsic stability toward Li and high chemical and electrochemical stabilities. After a decade of researches, many problems have been answered for LLZO-based CLB developments but still numerous challenges left to be solved. This review presents the latest efforts on the development of LLZO based CLBs, which covers the advances in LLZO crystal structure to increase its ionic conductivity and progresses in the use of Li as the electrode, regarding to its intrinsic chemical stability toward Li and interface elaboration for allowing Li dendrite suppression. On the positive electrode developments, chemical compatibility of various active materials and strategies to circumvent the incompatibility issue at high sintering temperatures are inspected.