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Energy management algorithms have a crucial role in electric vehicles due to their limited driving range. For an energy management algorithm to be effective, we should model the vehicle as accurately as possible. That is, not only the structure of the model should be accurate, but also the parameters of the model should be accurate. In this work, we take the model of an electric vehicle and tune three parameters in it based on trip data, namely, vehicle mass, air drag coefficient, and rolling resistance coefficient. We do this by using Least Squares method to set the initial guess and then by optimizing the parameters using Gradient Descent. To the best of our knowledge, this is the first work that simultaneously estimates these three parameters. Our work is also unique in the sense that it combines Least Squares and Gradient Descent.

State of Charge (SOC) estimation is critical for battery powered devices in order to find out the remaining charge level. This process is relatively straightforward when the battery is in the resting state. However, it can be challenging while the device is operating, due to the process disturbances and model uncertainties. Various kinds of approaches have already been proposed in the literature like Neural Networks, Kalman Filtering, and Nonlinear Observers. Nevertheless, proposed methods in the literature do not have fast response for initial condition errors. This paper proposes a new implementation of Extended Kalman Filter, which improves the convergence characteristics of states for SOC estimation. The importance of initial condition errors is articulated in this paper, especially from an automotive perspective.