Environmental Impact of Lead-Acid Batteries: A Review of Sustainable Alternatives for Production and Recycling Based on Life Cycle Analysis

Lead-acid batteries (LAB) continue to be one of the most widely used energy storage technologies worldwide, especially in the automotive sector and in backup systems. However, their use is a significant source of lead and sulfuric acid pollution, with negative impacts on the environment and human health. This review analyzes the environmental and health effects of LAB manufacturing, use, and recycling, and evaluates sustainable alternatives through life cycle analysis. A search was conducted in the Multidisciplinary Digital Publishing Institute (MDPI), Science Direct, and Springer databases, yielding more than 247 documents, from which 84 technical and scientific articles were selected, mostly from the last five years, excluding duplicates and irrelevant texts or those in languages other than English. The results reveal that conventional pyrometallurgical processes release between 30 and 50 kg of lead fumes per ton processed, causing concentrations of up to 5000 mg/kg of Pb in soils near informal plants, exceeding international limits by more than 25 times. In contrast, closed-loop hydrometallurgical technologies reduce emissions by more than 70% and increase secondary lead recovery, making them an environmentally friendly option. It is concluded that the sustainability of the LAB system requires technological innovation, effective regulation, and extended responsibility within an eco-friendly circular economy model.