Our derivations provide some useful general physical insights. The overpotentialdominant electrode with slower kinetics tends to dominate full cell electrochemical response, which makes it difficult to probe the properties of the other electrode. For pulse schemes, the corresponding fitness variables are directly proportional to the ratio of instantaneous power. This understanding is important, since assessing instantaneous power output is challenging without conducting experiments. These straightforward and explicit linear approximations provide a direct link between physically meaningful degradation parameters and power, offering a simplified pathway for evaluating the state of health of a battery system.