Study on synthesis and application of tetrabasic lead sulfate as the positive active material additive for lead-acid batteries

Tetrabasic lead sulfate (4BS) was used as a positive active material additive for lead-acid batteries, which affirmatively affected the performance of the battery. Herein, tetrabasic lead sulfate was synthesized from scrap lead paste that was formed through the production process of the lead-acid batteries. This solves the disposing problem of the scrap lead paste that is challenging in the production of the lead-acid batteries. Scrap lead paste was first pre-treated and the 4BS with high purity and crystalline was synthesized by sintering at the temperature of 450°C and hold time of 7 h. As demonstrated by X-ray diffraction and scanning electron microscopy test and Material Studio software calculation, the purity of synthesized 4BS is higher than 98 wt%, small particles have pillar forms and are evenly distributed. Moreover, the synthesized 4BS of 1 wt% was added to the positive lead paste and then valve-regulated lead-acid battery was made after the pasting, curing and formation processes. The effectiveness of the lead-acid batteries after adding 4BS as crystal seeds was evaluated, and the 100% charge–discharge cycle life of the new battery (523 times) was about 1.4 times higher than that of general lead-acid batteries (365 times).

SODIUM LAURYL SULFATE EFFECTS ON ELECTROCHEMICAL BEHAVIOR OF POSITIVE ACTIVE MATERIAL AND COMMERCIAL POSITIVE PLATES IN LEAD-ACID BATTERY

Sodium lauryl sulfate (SLS) is an anionic surfactant used in many applications such as cleaning and hygiene products, electroplating, etc. For the first time, effects of SLS as an electroyte additive on electrochemical behavior of positive active material and commercial positive plates have been studied by cyclic voltammetry (CV), eletrochemical impedance measurements. The electrode surface morphology after 20 cycles of CV was studied by using scanning electron microscopy (SEM). Results show that SLS additive significantly improves the conversion reactions of positive active material and therefore enhances charge/discharge capacity. By increasing SLS concentrate, crystalline structure of positive active material changed. The effects of SLS on kinetic parameters of positive electrode reactions are also discussed in this paper. The results showed that SLS is promising for use as electrolyte additive for lead- acid batteries.