High lithium ionic conductivity in the garnet-type oxide Li7−X La3(Zr2−X, NbX)O12 (X = 0–2)

Abstract Lithium garnet-type oxides Li7−XLa3(Zr2−X, NbX)O12 (X = 0–2) were synthesized by a solid-state reaction, and their lithium ion conductivity was measured using an AC impedance method at temperatures ranging from 25 to 150 °C in air. The lithium ion conductivity increased with increasing Nb content, and reached a maximum of ∼0.8 mS cm−1 at 25 °C. By contrast, the activation energy reached a minimum of ∼30 kJ mol−1 at the same point with X = 0.25. The potential window was examined by cyclic voltammetry (CV), which showed lithium deposition and dissolution peaks around 0 V vs. Li+/Li, but showed no evidence of other reactions up to 9 V vs. Li+/Li.

[1]  V. Thangadurai,et al.  New lithium-ion conductors based on the NASICON structure , 1999 .

[2]  E. Cussen.  The structure of lithium garnets: cation disorder and clustering in a new family of fast Li+ conductors. , 2006, Chemical communications.

[3]  Venkataraman Thangadurai,et al.  Fast Lithium Ion Conduction in Garnet‐Type Li7La3Zr2O12 , 2007 .

[4]  Norihito Kijima,et al.  Synthesis and structure analysis of tetragonal Li7La3Zr2O12 with the garnet-related type structure , 2009 .

[5]  V. Thangadurai,et al.  Li6ALa2Nb2O12 (A=Ca, Sr, Ba): A New Class of Fast Lithium Ion Conductors with Garnet-Like Structure , 2005 .

[6]  V. Thangadurai,et al.  Investigations on electrical conductivity and chemical compatibility between fast lithium ion conducting garnet-like Li6BaLa2Ta2O12 and lithium battery cathodes , 2005 .

[7]  R. D. Shannon.  Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides , 1976 .

[8]  Venkataraman Thangadurai,et al.  Li6ALa2Ta2O12 (A = Sr, Ba): Novel Garnet‐Like Oxides for Fast Lithium Ion Conduction , 2005 .

[9]  K. Hayashi,et al.  Crystal structures of La3Li5M2O12 (M=Nb, Ta) , 1988 .

[10]  G. Jellison,et al.  A Stable Thin‐Film Lithium Electrolyte: Lithium Phosphorus Oxynitride , 1997 .

[11]  P. Slater,et al.  Identification of the Li sites in the Li ion conductor, Li6SrLa2Nb2O12, through neutron powder diffraction studies , 2007 .

[12]  Takashi Uchida,et al.  High ionic conductivity in lithium lanthanum titanate , 1993 .

[13]  Venkataraman Thangadurai,et al.  Lattice Parameter and Sintering Temperature Dependence of Bulk and Grain-Boundary Conduction of Garnet-like Solid Li-Electrolytes , 2008 .

[14]  Jie Fu.  Fast Li+ Ion Conduction in Li2O‐Al2O3‐TiO2‐SiO2‐P2O2 Glass‐Ceramics , 2005 .

[15]  Preparation of positive LiCoO2 films by electron cyclotron resonance (ECR) plasma sputtering method and its application to all-solid-state thin-film lithium batteries , 2007 .