 Enhancement of the discharge capacity and cycle life of lead–acid batteries demands the innovative formulation of positive and negative electrode pastes that can be achieved through the modifications in the leady oxide morphology and the use of additives to control characteristics such as grain size, specific surface area, electrical conductivity, and chemical reactivity. In the present work, we describe a methodology for the improvement of the cycle life of lead oxide electrodes by the addition of multi-walled carbon nanotubes (MWCNT) and high-energy ball milling of leady oxide obtained by Barton and Sovema reactors. Positive and negative electrodes were produced and tested by cycling at constant discharge current. An improvement of 110% on the number of cycles over the unaltered Sovema electrode, and 168% over Barton electrode were found and attributed to the cured electrode morphology and the improved conductivity introduced by the addition of MWCNT. Symmetrical cells of high energy ball-milled leady oxide electrodes with MWCNT withstood 528 cycles, retaining more usable charge than its counterparts.