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 65Li(2)O center dot 27B(2)O(3)center dot 8SiO(2) or 40.2Li(2)O center dot 5.7Y(2)O(3)center dot 54.1SiO(2) 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.