<p>Electrolyte additives play a crucial role in enhancing the performance of lead-acid batteries. In this study, varying amounts of manganese sulfate (MnSO₄) were introduced into the electrolyte to investigate its effects on the LAB negative electrode. The results indicate that MnSO₄ significantly improves the reversibility of the negative electrode reaction and reduces plate internal resistance. Furthermore, batteries incorporating MnSO₄ exhibit superior specific discharge capacity and excellent rate capability. Notably, at an optimal concentration of 0.5 wt.%, the negative electrode delivered discharge capacities of 123.9 mAh g⁻¹ at 100&#xa0;mA&#xa0;g⁻¹and 89.0 mAh g⁻¹at 400&#xa0;mA&#xa0;g⁻¹. After 1000 cycles at 100&#xa0;mA&#xa0;g⁻¹, the electrode retained a discharge capacity of 106.8 mAh g⁻¹, representing a 79% improvement over the blank battery. Characterization analysis confirms that MnSO₄ not only enhances negative electrode formation efficiency but also effectively suppresses sulfation.</p>