Effect of Li content in ion conductivity of lithium silicate glasses

• Published in: Journal of alloys and compounds 2020-06, Vol.827, p.154253, Article 154253
• Main Authors: Rim, Young Hoon, Kim, Mac, Baek, Chang Gyu, Yang, Yong Suk
• Format: Article
• Language: English
• Subjects: Depolymerization; Electrical conductivity; Electrical impedance; Electrical resistivity; Glass; Ion transport; Lithium; Lithium ions; Lithium oxides; Lithium silicate; Low conductivity; Raman spectroscopy; Rayleigh equations; Silicon dioxide; Solid electrolytes
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2020.154253

We present the electrical and the phonon vibrational properties of Li2O–2SiO2 (LS12) and Li2O–SiO2 (LS11) glasses to exploit for lithium ion transport in the merits of solid electrolyte. Electrical impedance measurements are carried out in the frequency 100 Hz–30 MHz and temperature range 30–150 °C. Based on the theory of the modified fractional Rayleigh equation, we predict the number densities of the lithium ions in the lithium silicate glasses. As an increase in lithium content, the covalent interaction between the Li-cation and its local sites of network increases the number of the non-bridging oxygen (NBO) sites by the depolymerization of the silicate glass network. We find the fact that the number of NBOs in the LS11 glass increases a factor of two larger than the number of NBOs in the LS12 glass. A low conductivity of lithium oxide glasses is reflection of a long stay of the lithium ions in the NBO atoms. The partial Li+ ions in the lithium silicate glasses participate on the ac conduction through the NBO sites. •Li2O-xSiO2 (x = 1, 2) glasses were synthesized by melt quenching method.•The number densities of Li ions were estimated in the lithium silicate glasses.•The number of NBOs in LS11 glass increase to exactly the twice of it in LS12 glass.•The partial Li + ions participate on the ac conduction through the NBO sites.