A model that predicts the current density and potential distributions as a function of depth of discharge discharge rate and grid design has been developed for application to lead‐acid batteries. The calculated potential distributions are in excellent agreement with the observations reported in a companion paper. The effects of the ohmic resistance of electrodes on capacity and distributions of potential, current density, and local active material utilization are discussed. It is demonstrated that the model can be used to optimize the design of grids or current collectors commonly used in lead‐acid batteries.