Hydrometallurgical Recovery of Spent Lithium Ion Batteries: Environmental Strategies and Sustainability Evaluation

Abstract

Lithium ion batteries have been undergoing rapid development in the global market due to their superior performance. However, the soaring number of lithium ion batteries in the market presents serious disposal challenges at the end of life. Moreover, continuous mining processes are harmful to the environment. From the viewpoint of cleaner production and green chemistry, the efficient recovery and reutilization of spent lithium ion batteries are necessary. In this perspective, the overall process of lithium ion battery recycling, especially the recent advances of hydrometallurgical methods, are summarized, focusing on the leaching, separation, and purification processes. The proper disposal of the waste discharged during the recycling process is proposed, highlighting the mitigation of secondary pollution. In addition, the environmental impact of recycling processes is summarized and thoroughly evaluated by recent life cycle assessment studies, revealing the key role of recycling strategic metal elements toward sustainability in an anthropogenic cycle. Finally, the current challenges in this area are pointed out and perspectives on sustainable approaches, cleaner production, and life cycle assessment are proposed.

Upcycling Real Waste Mixed Lithium-Ion Batteries by Simultaneous Production of rGO and Lithium-Manganese-Rich Cathode Material

“…The Hummers’ method involves the use of sulfuric acid and potassium permanganate, both as intercalating and oxidizing species, and hydrogen peroxide, as a reducing agent. Excluding potassium permanganate, sulfuric acid and hydrogen peroxide are generally used to perform acid-reductive leaching of LIBs electrodic powder with high extraction yields for the target metals (Co, Ni, Mn) . The resulting solution obtained after the application of the Hummers’ method on the electrodic powder, that generally constitutes a liquid waste with high Mn concentration, was characterized by AAS and the solution composition (Hummers’ leachate) was reported in Table .…”

“…Excluding potassium permanganate, sulfuric acid and hydrogen peroxide are generally used to perform acid-reductive leaching of LIBs electrodic powder with high extraction yields for the target metals (Co, Ni, Mn). 29 The resulting solution obtained after the application of the Hummers' method on the electrodic powder, that generally constitutes a liquid waste with high Mn concentration, was characterized by AAS and the solution composition (Hummers' leachate) was reported in Table 1. As shown in Table 1, besides Mn added as KMnO 4 in the application of the Hummers' method, we also found all of the other metals contained in the electrodic powder.…”

Advances and Challenges on Recycling the Electrode and Electrolyte Materials in Spent Lithium-Ion Batteries

“…Acidity and type of the acid are the most effective properties for leaching the spent LIBs. [1] 1 mole of citric acid produces 3 mole H + , and presences strong acidity. [35] Moreover, citric acid can chelate with transition metal cations which will promote the further separation process of metal cations.…”

“…In the light of the lifetime of LIBs for EVs is 8-10 years and only 1-3 years for electronic products, the number of spent LIBs will increase subsequently. [1,2] It is estimated that by 2035, the amount of spent LIBs will increase to 6.8 million tons. [3] If the spent LIBs are not disposed of suitably, it will pollute the environment and threaten human health.…”

Effect of Hydrogen Peroxide on the Recovery of Valuable Metals from Spent LiNi0.6Co0.2Mn0.2O2 Batteries

“…[1,2] It is notable that the global LIB recycling market is expected to grow to $23.72 billion in 2030 from $1.78 billion in 2017. [3] In addition, spent LIBs can result in severe environmental pollution and have a threat to human health. [4][5][6] Hence, the recycling of spent LIBs is of great significance not only to bring enormous economic value, but also to protect the environment and avoid the risk of human health.…”