One of the main challenges in the implementation of renewable energy, such as solar or wind energy, is to balance the power grid during fluctuations in supply and demand. This requires the availability of the appropriate technology to store electrical energy. In this context, different methodologies are being developed and improved, including physical methodologies, which include pumped hydroelectric power plants and compressed air storage, as well as electrochemical methodologies, which consider fuel cells and rechargeable batteries. Within the latter group, redox flow batteries are one of the most interesting options due to their easy scalability and the possibility of developing safe, highly efficient, long-lasting and environmentally friendly systems. This project focuses on the use of metals from the Andalusian Pyrite Belt (Copper, Zinc, Lead, Cu-Zn-Pb) to develop efficient new generation batteries for renewable energy storage.