where j r is the diffusive flux on the surface, and n is the unit normal to the reactive surface. The reaction rate depends on the local state-of-charge and the local overpotential, which can be described via generalized Butler-Volmer kinetics . In this study, galvanostatic simulations are performed for a given (dis)charge rate. Consequently, a constant ionic flux is applied normal to the reactive surface of the secondary particle and is directly related to the current density. Then, at a (dis)charge rate of nC, the reaction rate is given by