What are the recycling technologies for used lithium-ion batteries?

　　The recycling technology of waste lithium-ion batteries is to separate valuable components in waste lithium-ion batteries according to their respective physical and chemical properties.

　　Recycling technology of waste lithium-ion batteries: mainly wet recycling technology.

　　The recycling technology of used lithium-ion batteries is to separate the valuable components of used lithium-ion batteries according to their respective physical and chemical properties. Generally speaking, the entire recovery process is divided into 4 parts: (1) pretreatment part; (2) electrode material repair; (3) leaching of valuable metals; (4) chemical purification.

　　In the recycling process, according to different extraction processes, the recycling technology of lithium-ion batteries can be divided into three categories: (1) dry recycling technology; (2) wet recycling technology; (3) biological recycling technology.

　　Dry recovery mainly includes mechanical separation and high temperature pyrolysis (or called pyrometallurgy). The dry recovery process is relatively short, and the recovery is not very specific. It is the preliminary stage to realize the separation and recovery of metals. It mainly refers to the method of directly realizing the recovery of materials or valuable metals without using media such as solution, mainly through physical separation and high-temperature pyrolysis, the battery is crushed and classified by coarse screening, or the organic matter is removed by high-temperature decomposition for further Element recycling.

　　Wet recovery technology is more complicated, but the recovery rate of each valuable metal is relatively high. It is currently the main technology for processing waste nickel-hydrogen batteries and lithium-ion batteries. Wet recovery technology uses various acid and alkaline solutions as the transfer medium to transfer metal ions from the electrode material to the leaching solution, and then through ion exchange, precipitation, adsorption and other means, the metal ions are removed from the form of salts, oxides, etc. Extract from the solution.

　　Bio-recycling technology has the characteristics of low cost, low pollution and reusability. It is the ideal direction for the development of lithium-ion battery recycling technology in the future. Biological recovery technology mainly uses microbial leaching to convert the useful components of the system into soluble compounds and selectively dissolve them to obtain a solution containing effective metals, to achieve the separation of target components from impurity components, and finally to recover valuable lithium and other valuable components. Metal. At present, the research on bio-recovery technology has just started, and then it will gradually solve the problems of the cultivation of high-efficiency strains, the long cycle, and the control of leaching conditions.

　　From the perspective of the sequence of the recycling process, the first step: the pretreatment process, the purpose of which is to initially separate and recover the valuable parts of the old lithium-ion battery, and efficiently and selectively enrich the high value-added parts such as electrode materials for subsequent recovery. The process went smoothly. The pretreatment process generally combines crushing, grinding, screening and physical separation methods. The main pretreatment methods include: (1) pre-discharge; (2) mechanical separation; (3) heat treatment; (4) lye dissolution; (5) solvent dissolution; (6) manual dismantling, etc.

　　Step 2: Material separation. The mixed electrode material of the positive electrode and the negative electrode is enriched in the pretreatment stage. In order to separate and recover valuable metals such as Co and Li from it, the mixed electrode material needs to be selectively extracted. The process of material separation can also be classified according to the classification technology of dry recovery, wet recovery and biological recovery: (1) inorganic acid leaching; (2) biological leaching; (3) mechanochemical leaching.

　　The third step: chemical purification. Its purpose is to separate, purify and recover various high value-added metals in the solution obtained in the leaching process. The leaching solution contains various elements such as Ni, Co, Mn, Fe, Li, Al, and Cu, among which Ni, Co, Mn, and Li are the main recovered metal elements. After the Al and Fe are selectively precipitated by adjusting the pH, the Ni, Co, Mn, and Li in the leaching solution are processed and recovered in the next step. Commonly used recovery methods are chemical precipitation, salting out, ion exchange, extraction and electrodeposition.

　　The technical route and trend of power battery recycling in domestic and foreign enterprises: wet process and high temperature pyrolysis are the mainstream. Compare the waste power battery recycling process of mainstream foreign battery recycling companies. It can be found that the current mainstream lithium battery recycling process is wet process and high temperature pyrolysis. Mainly, and a large part of it has been put into the industrial production stage.