Progress and Status of Hydrometallurgical and Direct Recycling of Li-Ion Batteries and Beyond

Abstract

An exponential market growth of Li-ion batteries (LIBs) has been observed in the past 20 years; approximately 670,000 tons of LIBs have been sold in 2017 alone. This trend will continue owing to the growing interest of consumers for electric vehicles, recent engagement of car manufacturers to produce them, recent developments in energy storage facilities, and commitment of governments for the electrification of transportation. Although some limited recycling processes were developed earlier after the commercialization of LIBs, these are inadequate in the context of sustainable development. Therefore, significant efforts have been made to replace the commonly employed pyrometallurgical recycling method with a less detrimental approach, such as hydrometallurgical, in particular sulfate-based leaching, or direct recycling. Sulfate-based leaching is the only large-scale hydrometallurgical method currently used for recycling LIBs and serves as baseline for several pilot or demonstration projects currently under development. Conversely, most project and processes focus only on the recovery of Ni, Co, Mn, and less Li, and are wasting the iron phosphate originating from lithium iron phosphate (LFP) batteries. Although this battery type does not dominate the LIB market, its presence in the waste stream of LIBs causes some technical concerns that affect the profitability of current recycling processes. This review explores the current processes and alternative solutions to pyrometallurgy, including novel selective leaching processes or direct recycling approaches.

Challenges in Ecofriendly Battery Recycling and Closed Material Cycles: A Perspective on Future Lithium Battery Generations

“…Leaching is the first step and describes the dissolution of metals via the usage of acids or bases. Typically, at first, the black mass is dissolved in NaOH and afterwards leached using H 2 SO 4 , with initial impurities such as iron, aluminum, and copper precipitated by small amounts of NaOH and sieving [46,47]. The purification is the second step in the process chain where the metals are separated and purified via e.g., selective chemical reactions.…”

“…For example, the individual metals can be further precipitated as sulfate salts by adding NaOH or other basic agents and increasing the pH. Selectively, this can be controlled by considering the different solubilities of the metal salts [46,47]. Hydrometallurgical process steps are capable of producing high product purities.…”

“…However, the electrolyte, binder, and conductive additives are lost for reuse. Nevertheless, the active material chemistry is retained and cannot be adapted to new requirements [47,51].…”

Lightweight Cement Conglomerates Based on End-of-Life Tire Rubber: Effect of the Grain Size, Dosage and Addition of Perlite on the Physical and Mechanical Properties

“…(Terlizzi, Bari, Italy). Moreover, in this case, the samples were prepared with 225 g of water and 450 g of cement [42], and the total volume of aggregate was set at 450, 600, and 750 cm 3 . Tables 3 and 4 report, respectively, the aggregate and mortar composition.…”

“…Industrial waste recycling and reuse are considered important issues to face the need for a more sustainable and environmentally friendly building trade in order to obtain an appropriate management of a large quantity of by-products such as agro-food waste [1], plastics [2], batteries [3], municipal solid waste [4], and glass [5][6][7]. Indeed, the construction industry has an extensive impact on raw materials consumption and waste production; accordingly, the reuse and the conversion of a waste into a new resource (recycling operation) is fundamental to increasing the sustainability of a product, the socalled secondary raw material that can be re-used in the construction industry [8][9][10][11] or in environmental applications [12][13][14][15].…”