Temperature Dependent Coulomb Counting Method for State of Charge Estimation of Battery

A battery’s State of Charge (SOC) indicates how much capacity or energy it still has stored. Nonlinear behaviour, ageing and degradation, temperature effects, high self-discharge, load changes, and a variety of other factors make estimation difficult. To overcome these difficulties in estimation combination of various methods and algorithms are required. The estimation of the initial state of charge is the primary flaw in the coulomb counting approach. For precise state of charge estimation, we proposed an improved version of the enhanced coulomb counting technique. Generic battery of 48V-30AH is designed and considered for evaluation of proposed method. Simulink model is developed considering situational awareness, non-linear characteristics such as driving loads, operational conditions. Measured SOC and modelled SOC are compared, and results show that they are almost similar. In the future work, the estimation accuracy will be improved by adaptive estimation, combining and comparing the similar estimation methods.