The mechanistic aspects of the beneficial effects of different manufacturing processes on the performance of lead/acid batteries have been studied using electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The implications of grid etching, active material compression and spiking of active material with conductive additives, along with various combinations of these processes, on the PAM and positive electrode corrosion layer have shown that a combination of compression and conductive additives reduces the PbSO4 content of both the positive active material (PAM) and the grid corrosion layer, leading to an enhancement in battery performance. Furthermore, the impact of the most promising battery manufacturing process on the kinetics of electrochemical processes occurring in the LAB, as studied using EIS, has shown that the charge transfer resistance of control cells in the fully discharged state increases with cycling, while the treated cells behaved like a near-perfect capacitor, yielding a negligible charge transfer resistance. EIS has shown that the kinetics of lead/acid battery processes in additive spiked and compressed cells is accelerated with respect to control cells.