Concerted migration typically occurs when multiple ions move together as a group rather than individually. By this the ions become more mobile and can move through the solid material more easily. This phenomenon is desirable because it can enhance the overall ionic conductivity of the solid material, enabling faster ion transport and thus improving the battery performance. It has already been demonstrated that similar phenomena significantly reduce the barriers of surface reactions when concerted reaction mechanisms are considered. Nevertheless, such a concerted motion of the ions is not well described with conventional diffusion models. While a comprehensive understanding of the migration mechanism has been provided, predicting E a = 0.5 eV for Li (E a = 0.3 eV) of same crystal framework and comparable energy landscapes. During concerted migrations, the Nernst-Einstein equation fails to uphold the approximate correlation between the tracer diffusion coefficient and the ionic conductivity. As a substitute, the charge diffusion coefficient D σ supersedes D tr , and the accurate manifestation of the Nernst-Einstein equation yields the ionic conductivity as: