Electrical, mechanical and chemical behavior of Li1.2Zr1.9Sr0.1(PO4)3

• Published in: Solid state ionics 2017-02, Vol.300 (C), p.38-45
• Main Authors: Smith, Sheila, Thompson, Travis, Sakamoto, Jeff, Allen, Jan L., Baker, David R., Wolfenstine, Jeff
• Format: Article
• Language: English
• ISSN: 0167-2738; 1872-7689
• DOI: 10.1016/j.ssi.2016.11.032

The elastic modulus, fracture toughness, ionic conductivity, Li and water stability of dense (~97%) fine-grain (~10μm) Li1.2Zr1.9Sr0.1(PO4)3 (LZSP) consolidated by reactive hot-pressing was investigated. Low values of elastic modulus (25.2 and 40.9GPa), fracture toughness (0.29 and 0.37MPa-m1/2), total conductivity (2.1×10−5S/cm) at room temperature were exhibited as a result of the presence of microcracks formed during cooling from the hot-pressing temperature. The lattice conductivity of LZSP is 0.85×10−4S/cm with an activation energy for bulk conductivity of 0.29eV. The results of Li/LZSP/Li cell impedance as a function of time and surface examination suggest that LZSP is not stable against metallic lithium. The results of the water stability test suggest that LZSP is a possible membrane for use in aqueous Li-Air cells. The results of this study reveal for the case of lithium zirconium phosphates are as follows: 1] a small grain size is required to prevent microcracking to avoid a reduction in total conductivity and mechanical properties and 2] even though they do not contain a transition metal cation they are not stable against Li at room temperature. •The elastic modulus, fracture toughness, ionic conductivity, Li and water stability of dense (~97%) fine-grain (~10 μm) Li1.2Zr1.9Sr0.1(PO4)3 (LZSP) consolidated by reactive hot-pressing was investigated. Low values of elastic modulus (25.2 and 40.9 GPa), fracture toughness (0.29 and 0.37 MPa-m1/2), total conductivity (2.1×10-5 S/cm) were exhibited as result of the presence of microcracks formed during cooling from the hot-pressing temperature.•The lattice conductivity of LZSP is 0.85×10-4 S/cm with an activation energy for bulk conductivity of 0.29 eV.•The results of Li/LZSP/Li cell impedance as a function of time and surface examination suggest that LZSP is not stable against metallic lithium.