We envision that in the future, these methods could help detect critical transitions in degradation, often referred to as "knees," where it has been predicted that the electrode undergoes major changes in degradation . Such transitions are challenging to discern using conventional techniques, but our method allows for the determination of dominant degradation mechanisms for each electrode in operando. This provides a pivotal method of detection and prevention of battery failure. In addition, determination of the failure mechanism can also guide the selection of a second life application of the degraded battery . Some drawbacks of our approach include the fact that the impact of degradation on the kinetics of the electrode material must be physically understood to be included in the model. In addition, mathematical models of the reaction kinetics must be selected before the optimization can be performed, although one can imagine automating this process with inverse learning from data. Chemo-mechanics and microstructural effects have also been neglected. It is also essential to acknowledge that some degradation mechanisms, such as lithium plating and surface degradation in nickel-rich materials, can have similar electrochemical signatures, posing challenges in their differentiation. In addition, though the theoretical analysis of these experiments has revealed much about the practicality and also limitations of HPPC diagnostics, experimental validation is a crucial step. Forthcoming works will be focused on improved design-of-experiments for optimal HPPC and rigorously verifying these methods through experiments. Following the protocols in Ref. , we see that for a reference electrode, if the foil reaction is defined with a simple Butler-Volmer reaction as