A facile route to search antioxidant additives for dry charged negative plate of the lead acid battery

Here we report a new way to characterize the performance of antioxidant additives for dry charged negative plate of the lead acid battery by measuring the anodic excursion peaks (AEPs). Cyclic voltammetry (CV), and linear sweep voltammetry (LSV) combined with potential step method have been conducted to investigate the effects of polyhydric compounds (sorbitol) and cetyltrimethyl ammonium bromide (CTAB) on AEPs and corrosion resistance. The results show that sorbitol increases AEPs but prevents the formation of PbO2, and on the contrary CTAB promotes the formation of PbO2 but eliminates AEPs. These phenomena reveal that the increase of AEPs and the increase of corrosion resistance of lead electrode are synchronous, which indicate that the additives that can enhance AEPs could be used as antioxidant additives. The effectiveness of the new AEPs test on searching antioxidant additives for protection of lead electrode has been compared with the general potentiodynamic polarization (Tafel) method, and the results of the two tests are consistent. Also, it has been obtained that characterizing the antioxidative effect of antioxidant additives on lead electrode via measuring AEPs in CV or LSV is reliable and more facile than Tafel.

► AEPs has been exploited to characterize antioxidant for lead acid batteries.
► AEPs was increased by usually used antioxidant and sorbitol but eliminated by CTAB.
► The higher the AEPs is, the higher the corrosion resistance is.
► The mechanism of the inhibition of sorbitol on corrosion of Pb has been suggested.