20 Apr 2026

A Simple Room-Temperature Refurbishment Method for Sulfated Lead-Acid Batteries Using Ammonium Acetate Treatment

Abstract: Current recycling paradigms of lead-acid batteries (LABs) involve the use of toxic, polluting, and energy- demanding processes. Here we report a novel strategy to refurbish LABs which failed due to the formation of hard sulfation on the anodes. We used ammonium acetate (NH4Ac) to selectively dissolve the water-insoluble lead sulfate (PbSO4) crystals which cause the hard sulfation from commercial LAB anodes and electrodeposit metallic lead on a new surface. The remarkable removal of hard sulfation was characterized by a combination of X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX). The treatment replenished a fresh LAB anode surface, recovering the capacity from ~0 % to 99 %. The dissolved Pb2+ was retrieved with an efficiency of >99.9 % through electrodeposition, completing a refurbishing process that minimizes the release of heavy metals into the environment. We demonstrated a proof-of-concept refurbishing of a full commercial LAB, which recovered 35 % of its capacity. With a noteworthy capacity renewal and minimal release of hazardous materials, NH4Ac refurbishing promises to be an environment-friendly and economic alternative recycling paradigm for the LAB industry.