Lead Sulfate As The Positive Active Material Of Lead Acid Batteries

Traditionally, the materials used in lead acid battery are leady oxide. the oxidation of metallic lead consume long time in the process of producing, and require considerable energy and space. The above-mentioned problems can be avoided if PbSO4 used as the active materials directly. Moreover, it could make producing and recycling simplified and pollution reduced. We proved that PbSO4 can be used as the negative active materials, but we had found that the electrochemical property of PbSO4 is poor when used as the positive active materials. Consequently, we need to find out possible ways to improve the electrochemical performance of PbSO4.Firstly, PbSO4 is prepared by facile chemical precipitation of aqueous lead acetate, lead nitrate and lead chloride with sodium sulfate, respectively. The particles size of PbSO4 is about 1～10 μm, they are flaky, rod-shaped and gravel, respectively. Adding 20 wt.% of PbO2, the electrochemical property of PbSO4 prepared by aqueous lead acetate with sodium sulfate is the best. PbSO4 prepared by aqueous lead acetate with sodium sulfate mixtures with different ratios 0%、10%、5%、20%、25%、30%、40%、50% and 100% of PbO2, respectively. The mixtures containing 20% and 30% discharge 80.51 mAh/g and 82.69 mAh/g, the utilization of samples are 43.34% and 43.31%, Also, the one with 20% PbO2 remains 90% capacity in 300 100% Depth of discharge cycles.PbSO4 mixtures with different ratios 0%、2%、5%、10%、20%、30%、40% and 70% of Pb3O4. The mixtures containing 2% and 5% discharge 60 mAh/g and 77 mAh/g in the current density of 100 mA/g, the mixtures containing 10%～70% discharge 90 mAh/g. The utilization of the mixtures containing 5%、10%、20% and 30% of Pb3O4 are 43.5%,50.9%, 46.7%,47.1%, respectively. XRD and surface morphology of the samples containing 0%、 5%、10%、20% and 30% of Pb3O4 are examined after curing and formation. The results show that Pb3O4 is helpful for PbSO4 formation, but it has no effect on PbSO4 curing. Also, the one with 10% Pb3O4 remains 93% capacity in 150 100% DOD cycles.Lastly, different ratios 5%、10%、20%、30% and 40% of tetrabasic lead sulfate were added in PbSO4, its electrochemical properties are still poor, the one with 40% discharge only 50 mAh/g. We also mixture with 10% of Pb3O4 base on mixture with 40% 4BS, the discharge capacity reach to 104 mAh/g.