Stability of composite electrolytes based on Li7La3Zr2O12 to metallic lithium.

The stability of the composite electrolytes based on tetragonal and cubic modification of Li₇La₃Zr₂O₁₂ with 65Li₂O·27B₂O₃·8SiO₂ or 40.2Li₂O·5.7Y₂O₃·54.1SiO₂ glass addition versus metallic lithium in stationary conditions and under constant current applied is studied in the paper. A complex of electrochemical techniques established the growth of symmetric cell resistance and overvoltage in measuring cell for composites based on tetragonal Li₇La₃Zr₂O₁₂, which denotes the degradation of the solid electrolyte surface for tetragonal Li₇La₃Zr₂O₁₂–x wt% glass electrolytes due to the formation of the impurities confirmed by XRD. The resistance of the symmetric cells with composite electrolytes based on cubic modification of Li₇La₃Zr₂O₁₂ does not change in the course of the experiment and the voltage reaches the plateau at constant current applied. Thus, composites based on the cubic Li₇La₃Zr₂O₁₂ with a small addition of lithium boron-silicate and yttrium-silicate glasses are stable versus lithium. Moreover, the cross section of the samples remains white colored after electrical testing and no dendrite formation is observed. [ABSTRACT FROM AUTHOR]