Search

Spent LiFePO4 batteries are gradually increasing in popularity and interest, and their stable and insoluble olive-shaped structure poses a great challenge for the sustainable recycling of Li. In this study, a simple and sustainable Ca(ClO)2 system was proposed for the recovery of spent LiFePO4 battery cathode materials. The effects of both mechanochemical activation and hydrometallurgical enhanced leaching on the deconstruction of LiFePO4 and the leaching rates of Li and Fe in the Ca(ClO)2 system were studied. Compared with mechanochemical activation, Ca(ClO)2-assisted hydrometallurgical enhanced leaching can simultaneously achieve the separation and enrichment of the target components Li+ and Fe3+ and the Ca2+ impurities. The transformation path and reaction mechanism of LiFePO4 in the Ca(ClO)2 system were proposed based on the phase composition and micromorphology of the reaction products. In addition, the economic evaluation results show that Ca(ClO)2-assisted hydrometallurgical enhanced leaching has a high recovery economy. The developed Ca(ClO)2 system realizes the strong dissolution of spent LiFePO4 battery cathode materials and the sustainable comprehensive recovery of valuable components. [ABSTRACT FROM AUTHOR]

• A facile-fast process was established for spent LiFePO 4 batteries recycling. • Mechanical mechanism and chemical mechanism jointly reveal the mechanochemical activation process. • The precursors of Li 2 CO 3 and FePO 4 were prepared by selective recovery of Li, Fe and P. • Advanced mechanochemical oxidation technology creates an acid-free environment. • The 4-minute activation time shows high economic benefits. As LiFePO 4 (LFP) gradually becomes the leader in the energy storage and power battery field, achieving a green and efficient industrialized recovery of Li from the stable lattice structure of LFP has become a significant requirement for driving resource and environmental sustainability. Here, a non-acid wet ultra-fast mechanochemistry reaction (UMR) instantaneous metallurgy technology is proposed, water leaching has obvious green and sustainable advantages. Including the wet mechanochemical reaction of C 10 H 14 N 2 Na 2 O 8 assisted H 2 O 2 and water leaching to deconstruct the orthorhombic olivine structure, and an innovative, detailed explanation of the mechanism of this technology is presented from the perspective of the synergy between mechanics and chemistry. The results indicate that under optimal conditions, stress energy accumulation and single-factor conditions can instantly achieve the activation process of efficiently deintercalating Li and enriching Fe in a single step within 4 mins, while still maintaining the olivine structure. Through the coupling of UMR with chelation reactions, the fastest selective recovery of 99.17 % of Li is achieved. Following filtration and precipitation, Fe and Li are ultimately recovered in the form of FePO 4 and Li 2 CO 3 precursors, respectively. Grey correlation analysis, grain flows numerical simulation, and the mechanism of chemical reactions indicate that rotation speed is the most critical factor affecting Li recovery, leading to the desorption of Fe(III) and Li+ mainly caused by the wear to the lattice structure by normal cumulative force, energy accumulation dissipation-induced advanced oxidation reactions, and chelation reactions. The non-acid USMR reported in this study offers a sustainable new pathway for the rapid extraction of Li from spent LFP for industrial purposes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A facile new process was established for spent LiFePO 4 batteries recycling. • Revealing conversion mechanism in (NH 4) 2 S 2 O 8 -assisted mechanochemical activation. • Closed-loop recycling of Li, Fe and P as high purity Li 2 SO 4 and FePO 4 /C. • A 1.0 kg scale up experiments showed a good economic benefits. With the rapid development of the lithium-ion battery industry, safe disposal of spent LiFePO 4 batteries (SLFPBs) has gradually become a focus of attention. However, the stable olivine structure of LiFePO 4 prevents deconstruction and separation of the elements Li, Fe and P. Mechanochemical activation proved to be an effective and environmentally friendly method for phase deconstruction. An efficient recycling method involving (NH 4) 2 S 2 O 8 -assisted mechanochemical activation and water leaching is reported herein for the deconstruction of SLFPBs. The results indicated that advanced oxidation of the (NH 4) 2 S 2 O 8 and synergistic mechanical forces accelerated the deconstruction of the LiFePO 4 mineral phase. Efficient leaching of the Li and targeted enrichment of the Fe and P were achieved simultaneously while preserving the olivine structure. Under the optimal conditions, the leaching efficiency for Li was 95.3%, and the leaching efficiencies for Fe and P were both less than 1.5%. A Li 2 SO 4 purity of 98.8% was obtained by evaporative crystallization and roasting. A 1.0 kg scale-up experiment showed that an economic profit of $4.768 was generated by recycling 1.0 kg of SLFPBs. This inexpensive, green and sustainable recycling method shows great potential for industrial planning. [ABSTRACT FROM AUTHOR]