I. Introduction
State-Of-Charge (SOC) is a crucial parameter in the battery management systems of electric vehicles that indicates the amount of charge left in its batteries [1]. Accurate SOC estimation is essential in ensuring the longevity and safety of the lithium-ion (Li-ion) batteries. The formal definition of SOC is the ratio of available capacity Q at time, t, to the nominal capacity [2] as given in the following equation: \begin{equation*} {\rm{SOC}} = \frac{{Q\left(t \right)}}{{{Q_n}}}\tag{1} \end{equation*}