Estimation of state of charge of lithium-ion battery taking into account temperature effects

Lithium-ion batteries have a high capacity for storing energy and power. That is why it is very common to use them in fast-charging stations as energy storage. Due to the fact that the battery of a system is closed, it is not possible to accurately calculate the amount of power stored in it. Using the battery charge level indicator allows a relatively accurate estimate of the amount of power and energy stored in the battery. One of the most widely used estimation methods is the Kalman filter and the H-infinity filter. Modeling, determining the exact capacity of the battery, and how to estimate its charge level is one of the most important and difficult techniques to ensure efficient and safe battery operation. Because the capacity and charge level of a battery are highly correlated, it is difficult to accurately estimate charge level without knowing the exact capacity of the battery. On the other hand, battery performance is partly dependent on temperature effects. Using the offline parameters of the battery allows the algorithm to estimate the battery temperature in addition to the battery charge level. This indicator can be used as a control signal by estimating the battery temperature moment.