Compatibility of Li[sub 7]La[sub 3]Zr[sub 2]O[sub 12] Solid Electrolyte to All-Solid-State Battery Using Li Metal Anode

Abstract

Electrochemical properties of Li7La3Zr2normalO12 (LLZ) were investigated to reveal its availability as a solid electrolyte for all-solid-state rechargeable batteries with a Li metal anode. After calcination at 1230°C , a well-sintered LLZ pellet with a garnet-like structure was obtained, and its conductivity was 1.8×10−4Scm−1 at room temperature. The cyclic voltammogram of the Li/LLZ/Li cell showed that the dissolution and deposition reactions of lithium occurred reversibly without any reaction with LLZ. This indicates that a Li metal anode can be applied for an LLZ system. A full cell composed of a LiCoO2/LLZ/Li configuration was also operated successfully at expected voltage estimated from the redox potential of Li metal and LiCoO2 . Simultaneously, an irreversible behavior was observed at the first discharge and charge cycle due to an interfacial problem between LiCoO2 and LLZ. The discharge capacity of the full cell was 15μAhcm−2 . These results reveal that LLZ is available for all-solid-state lithium batteries.

Li Ion Dynamics in Al-Doped Garnet-Type Li7La3Zr2O12 Crystallizing with Cubic Symmetry

“…The high lithium-ion conductivity of such ceramics showing good electrochemical stability to lithium metal makes them promising candidates to be used, for example, in thin-film batteries [9].…”

Tetragonal Li10GeP2S12 and Li7GePS8 – exploring the Li ion dynamics in LGPS Li electrolytes

“…The lack of suitable materials triggered intense research efforts in the eld of solid state ionics. During recent years signicant progress has been achieved, such that the materials available now are suitable for commercial applications.2 Hereby, two main classes of solid electrolytes have attracted the attention of both academia and industry, namely (i) oxide-based garnet-type electrolytes such as Li 7 La 3 Zr 2 O 12 , [3][4][5] and (ii) sulde-based electrolytes.6-8 The oxide-based materials generally show a wider electrochemical window, whereas the sulde-based electrolytes usually exhibit a higher Li-ion conductivity. In 2011, a new solid electrolyte Li 10 GeP 2 S 12 (LGPS), a metastable phase occurring in the system xLi 4 GeS 4 : yLi 3 PS 4 , was reported.…”

“…2 Hereby, two main classes of solid electrolytes have attracted the attention of both academia and industry, namely (i) oxide-based garnet-type electrolytes such as Li 7 La 3 Zr 2 O 12 , [3][4][5] and (ii) sulde-based electrolytes.…”

Electrolytes for high-energy lithium batteries

“…Li 7 La 3 Zr 2 O 12 (LLZ) was calcined to obtained garnetlike structure pellet that in a symmetric Li cell showed interfaced stability, reversible plating and de-plating with no reaction. However, Li/LLZ/LiCoO 2 cell that was successfully cycled showed irreversible behavior between LLZ and LiCoO 2 (Kotobuki et al 2010b).…”