Such applications include automotive starting lighting and ignition (SLI) and battery-powered uninterruptable power supplies (UPS). Lead acid battery cell consists of spongy lead as the negative active material, lead dioxide as the positive active material, immersed in diluted sulfuric acid electrolyte, with lead as the current collector:
The lead-acid battery is a kind of widely used commercial rechargeable battery which had been developed for a century. As a typical lead-acid battery electrode material, PbO 2 can produce pseudocapacitance in the H 2 SO 4 electrolyte by the redox reaction of the PbSO 4 /PbO 2 electrode.
The negative side was protected by a thin lead sheet, which was adhered to the core layer by using graphite-filled epoxy adhesive. Saakes et al. proposed an innovative composite substrate for fabricating fast discharge 4 V bipolar lead-acid batteries.
The use of lead acid batteries for energy storage dates back to mid-1800s for lighting application in railroad cars. Battery technology is still prevalent in cost-sensitive applications where low-energy density and limited cycle life are not an issue but ruggedness and abuse tolerance are required.
Due to the production of hydrogen at the positive electrode, lead acid batteries suffer from water loss during overcharge. To deal with this problem, distilled water may be added to the battery as is typically done for flooded lead acid batteries.
One major cause of failure is hard sulfation, where the formation of large PbSO 4 crystals on the negative active material impedes electron transfer. Here, we introduce a protocol to remove hard sulfate deposits on the negative electrode while maintaining their electrochemical viability for subsequent electrodeposition into active Pb.