Achieving high performances of lead-carbon battery with MnO2 positive additive

The development of the related negative additives renders the positive electrode as essential factor limiting the further upgrade of advanced lead-carbon battery. In this study, conductive manganese dioxide (MnO2) materials as functional additives were introduced into the positive electrode of lead-carbon batteries to boost the electrochemical activity. The effect of MnO2 additive on the substances conversion during curing and formation stages were investigated, also the specific capacity, rate and cycling durability. The results reveal that the MnO2 additive could accelerate the charge transfer in the positive electrode and promote the conversion kinetic between PbSO4/PbO2 phases. When the doping amount of MnO2 is 0.1 wt%, the modified lead-carbon batteries delivered an initial specific capacity of 60.74 mAh g-1, which was 24% higher than the blank sample. Besides, the lead-carbon batteries with MnO2 positive additive also display impressive rate capacity and excellent cycle stability, which could retain the capacity retention rate of 89.2 % after 150 cycles under 100 % DOD condition. The excellent performances could be attributed to the fact that MnO2 could facilitate the conversion within the positive active material, reduce the generation of large PbSO4 crystals, and remarkably enhance the utilization rate of positive active materials during the charging/discharging processes.