During the last decades, huge efforts have been made to enhance the efficiency as well as performance of lead–acid batteries. The configuration of grid wires plays an important role in minimizing the ohmic drop and hence, improving its current collecting ability. In the current study, numerical methods have been employed to investigate the effects of grid configuration on the performance of a positive electrode in lead–acid batteries. Potential and current density distributions have been modeled through grid wires, active material and adjacent electrolyte to the surface of each grid. The modeling results are consistent with experimental findings in the literature saying that the optimized diagonal design for grid configuration provides lower total grid weight as well as enhanced current collecting role comparing to other designs such as, conventional, diagonal and expanded metal. This confirms that numerical modeling is a fast, inexpensive and effective method for optimization of the battery grid configuration.