The diffusion couples of lanthanum‐based barium borosilicate glass with high‐ and low‐temperature electrolytes have been heat‐treated at 850°C and 800°C, respectively, for 5, 100 and 750 h. These prepared diffusion couples have been characterized using various techniques like X‐ray diffraction (XRD), scanning electron microscopy (SEM), X‐ray dot mapping, and electron probe microanalysis (EPMA). The thermodynamic parameters like frequency factor, crystallization constants, free volume, and bulk thermal expansion coefficients have been calculated to understand the behavior of glass. Interestingly, glass revealed self‐healing tendency with heat treatment duration.