In response to the increasingly prominent problems of security and environment of energy, lithium-ion power batteries were recognized as the most potential power battery to alleviate the difficulties because of its high energy density, fast charging and discharging speed, long cycle life environment friendly. Thanks to the strong support of the national support policy, it had been widely used in the field of new energy vehicles. The spent lithium-ion batteries contained valuable components such as cobalt, lithium, copper, nickel and graphite etc. with great recycling value, on the other hand, it contained toxic and harmful substances such as heavy metal ions and organic carbonates. So, it was obvious that the spent lithium-ion battery had both resource and hazard characteristics, which would pose a great threat to the environment if not treated properly. So, recycling and innocuity treatment of that had become a research hotspot. Physical separation was a process to separate and purify the components of spent lithium-ion battery according to the differences in particle size, specific gravity, magnetism, wettability, friction charge and other physical properties.Physical separation technology was the method which could realize the pre-concentration of lithium, cobalt, copper, manganese and other metals in the treatment of spent lithium-ion batteries environmentally friendly and economically, which showed great potential in combination with other technologies to separate and purify the useful components. However, compared with metallurgical purification technology, the related research and reports of which were relatively few, and the systematic theory and efficient separation technology had not yet been formed.In this paper, the recovery of spent lithium-ion batteries by physical separation technology including crushing, screening, gravity separation and flotation and combination of which at home and abroad in recent years were introduced, and the advantages and disadvantages of each process were introduced and compared with detailed examples.The main conclusions were as follows: (1) In the process of crushing of spent lithium-ion battery cell, the selective crushing effect should be expanded as much as possible, so that the crushed products could be efficiently concentrated in the specific particle size fraction. Besides, special attention should be paid to the disposal of electrolyte, which was a safety problem that could not be ignored. (2) Flotation was an effective method to separate the cathode material and graphite from the electrode mixture, it had the advantages of low cost, low energy consumption, strong applicability and little harm to the environment. In the process of industrial application, low toxicity, economic and efficient removal of the binder which affected the flotation effect greatly was the most critical technical problem. (3) Physical separation created favorable conditions for subsequent separation in treatment of spent lithium-ion batteries, it was pointed out that the combined pretreatment by combined processes had showed a good application prospect.In order to further improve the purity of separation products, it was pointed out that it must strengthen the research of physical separation technology to improve the purity of sorting products, and the process of high efficiency, low cost, low pollution was the development direction of in future. To overcome the weakness of physical separation such as low product purity and incomplete disposal of harmful substances, some effective managements must be taken in: (1) According to the material and structure characteristics of different spent lithium-ion batteries, the crushing methods should be selected to expand the selective crushing effect, and the study on the properties of crushed products should be strengthened, so as to lay the foundation for the formulation of reasonable physical separation process. (2) In the process of physical separation and pretreatment of spent lithium-ion battery, it was necessary to strengthen the research on low-cost and high-efficiency recovery technology of useful components such as separator, anode material and electrolyte of them. Special attention should be paid to the treatment of toxic and harmful substances of waste batteries, no matter what process was selected. (3) When selecting the treatment process, interdisciplinary integration should be emphasized to change or optimize the physical and chemical properties such as magnetism, specific gravity and floatability of some components of spent lithium-ion battery by appropriate methods, so as to achieve the purpose of green, efficient and economic recycling.(4) Physical separation should not be simply regarded as the pretreatment process in the recovery process. The combination of physical separation with hydrometallurgy, pyrometallurgy and bio-metallurgy would be an important research content of recycling spent lithium-ion batteries in the future. © Editorial Office of Chinese Journal of Rare Metals. All right reserved.
