As the demand for batteries continues to surge in various industries, effective recycling of used batteries has become crucial to mitigate environmental hazards and promote a sustainable future. This review article provides an overview of current technologies available for battery recycling, highlighting their strengths and limitations. Additionally, it explores the current challenges faced by the industry and discusses potential future advancements. Through an in-depth analysis of the state-of-the-art recycling methods, this review aims to shed light on the progress made in battery recycling and the path ahead for sustainable and efficient battery waste management.

Photovoltaic panels were included in EU Directive as WEEE (Wastes of Electric and Electronic Equipment) requiring the implementation of dedicated collection schemes and end-of-life treatment ensuring targets in terms of recycling rate (80%) and recovery rate (85%). Photovoltaic panels are mainly made up of high-quality solar glass (70–90%), but also metals are present in the frames (Al), the cell (Si), and metallic contacts (Cu and Ag). According to the panel composition, about $72 per 100 kg of panels can be recovered by entirely recycling the panel metal content. The PhotoLife process for the treatment of end-of-life photovoltaic panels was demonstrated at pilot scale to recycle high value glass, Al and Cu scraps. A process upgrade is here reported allowing for polymer separation and Ag and Si recycling. By this advanced PhotoLife process, 82% recycling rate, 94% recovery rate, and 75% recoverable value were attained. Simulations demonstrated the economic feasibility of the process at processing capacity of 30,000 metric ton/y of end-of-life photovoltaic panels.

The aim of the present work is the recycling treatment of tubular α-Al₂O₃-supported ceramic membranes with a Pd/Ag selective layer, employed in hydrogen production with integrated CO₂ capture. A nitric acid leaching treatment was investigated, and recovered ceramic supports were characterized, demonstrating their suitability for the production of novel efficient membranes. The main objective was the metal dissolution that preserved the support integrity in order to allow the recovered membrane to be suitable for a new deposition of the selective layer. The conditions that obtained a satisfactory dissolution rate of the Pd/Ag layer while avoiding the support to be damaged are as follows: nitric acid 3 M, 60 °C and 3.5 h of reaction time. The efficiency of the recovered supports was determined by nitrogen permeance and surface roughness analysis, and the economic figures were analysed to evaluate the convenience of the regeneration process and the advantage of a recycled membrane over a new membrane. The experimentation carried out demonstrates the proposed process feasibility both in terms of recycling and economic results.

An innovative cryo-mechano-hydrometallurgical process (named LIBAT) was demonstrated at pilot scale for the treatment of EOL lithium primary batteries with chemistry Li(0)-MnO₂. The process allowed the recycling of steel scraps from external cases after cryomechanical dismantling, and the recovery of Mn and Li products after hydrometallurgical processing. During demonstration activities, about nine tons of batteries were treated in the cryomechanical section, and one ton of black mass was treated in the hydrometallurgical section for the recovery of Mn hydroxides and Li₂CO₃. The environmental impacts of the process were evaluated in comparison with an innovative pyrometallurgical approach allowing Li recovery, confirming the benefits of the proposed process due to a reduction in energy consumption. Process simulations were performed considering different mixture feeds (only Li primary, or mixture with Li-ion batteries) and process options (only the cryomechanical section of the integral process) to assess the lower limits of potentiality that would ensure economic sustainability.

Li primary batteries are currently treated along with other Li batteries in several big pyro- metallurgical plants in Northern EU countries. Nevertheless, pyro-metallurgical processes do not allow for Mn and Li recycling and present negative environmental impacts, on the other hand hydrometallurgical processing can potentially ensure the integral recovery of all materials in Li primary batteries. In this work, preliminary experimental findings obtained in the LIFE-LIBAT project (LIFE16 ENV/IT/000389) are reported. In this project, end of life Li(0)-MnO₂ batteries were cryo-mechanically treated and then the metals were recovered by a hydrometallurgical process. Representative samples of end of life Li(0) batteries were characterized by type and composition. Batteries were stabilized in an N₂ bath and then crushed, sieved, and magnetically separated in the SEVal pilot units. Separated fractions (fine fraction, magnetic coarse fraction, and non-magnetic coarse fraction) were chemically characterized for target metal content (Li and Mn). Fractions were first treated for Li extraction and recovery, then the fine fraction was also leached for Mn recovery. Mass balances evidenced a 55% recycling rate and process simulations outlined profitability in the potentiality range in agreement with battery collection fluxes.