Recovery and regeneration of LiFePO₄ from spent lithium ion batteries via a novel pretreating process

Recently, the recycling of spent LiFePO₄ batteries has received extensive attention due to their environmental impact and economic benefit. In the pretreating process of spent LiFePO₄ batteries, the separation of the active materials and the current collectors determines the difficulty of recovery process and the quality of product. In this work, a facile and efficient pretreating process is first proposed. After only freezing the electrode pieces and immersing it in boiling water, LiFePO₄ materials have been basically peeled from Al foil. Then, after roasting in an inert atmosphere and sieving, all of the cathode and anode active materials were separated from Al and Cu foils easily and efficiently. The active materials were subjected to acid leaching and the leaching solution further prepared FePO₄ and Li₂CO₃. Finally, the battery-grade FePO₄·and Li₂CO₃ were used to re-synthesize LiFePO₄/C via the carbon thermal reduction method. Re-synthesized LiFePO₄/C cathode exhibits good electrochemical performance, which satisfies the requirement for middle-end LiFePO₄ batteries. The whole process is found to be environmental and have great potential for industrial-scale recycling of spent lithium-ion batteries.