Determining the State of Charge and the State of Health of a Battery Pack

In this paper, a state of charge (SOC) and state of health (SOH) mobile estimation lab is developed, and the error of the setup is quantified. Multiple implementations for estimating the SOC and SOH are outlined below. However, the coulomb counting estimation method is employed to estimate the SOC, while the linear regression of the SOC is used to estimate the SOH. This is accomplished by using a current probe connected to an oscilloscope to record current levels. The data acquired inputs into a Matlab script, which calculates the SOC and SOH values. Experimental data show that this implementation can estimate the SOC value and thus the implementation can also estimate the SOH. However, a standalone coulomb counting implementation has a couple of drawbacks. These drawbacks and ways to overcome these drawbacks are detailed below. The setup is validated by the open-circuit voltage method, and it is figured out that the error of this implementation grows at 0.0013 ΔSOC/minute.