Lithium-ion battery recycling technology equipment

Lithium-ion battery is the best rechargeable chemical battery with the best technical performance in the world. It has the advantages of high working voltage, large specific energy, long cycle life, small self-discharge, no memory effect, and no pollution. It is widely used in mobile communications, notebooks, etc. Computers, portable tools, electric bicycles and other fields. Due to the huge consumption of lithium batteries, the consumption of non-renewable metal resources is quite large. Therefore, it is of great significance to recycle metals with high economic value and large content in lithium-ion batteries to achieve energy saving, emission reduction and sustainable development.

The cobalt and aluminum that need to be recovered in lithium-ion batteries are mainly concentrated on the positive electrode material cobalt-lithium film. The main components of the cobalt-lithium film are LiCoO2 active material, conductive acetylene black, aluminum foil current collector and PVDF (polyvinylidene fluoride) adhesive .

1. Recycling of lithium-ion battery casings

Lithium battery casings include steel casings (square type is rarely used), aluminum casings, nickel-plated iron casings (used for cylindrical batteries), aluminum-plastic film (soft packaging), etc., as well as battery caps, which are the terminals of the positive and negative electrodes of the battery. Before recycling the casing, the waste lithium battery needs to be pre-discharged before dismantling, and the disassembled plastic and iron casing can be recycled. Usually there are: mechanical crushing and screening method, that is, through mechanical crushing, sieving, and sorting out the shell material; manual dismantling, considering the harm to the human body, try not to use this method; The technology is very environmentally friendly, but it can only recycle some metal materials and lithium salts, and the recycling efficiency is low, and it is impossible to effectively recycle plastics.

2. Recycling of cathode materials

Lithium-ion batteries use lithium-containing compounds as the positive electrode, only lithium ions, no metal lithium. Usually lithium manganese oxide, lithium cobalt oxide, lithium iron phosphate, nickel cobalt lithium manganese oxide and other materials, most of the positive electrode active material of lithium ion batteries still use lithium cobalt oxide, because nickel cobalt lithium manganate combined with lithium manganate The advantages of the two materials, lithium cobalt oxide and lithium cobalt oxide, have attracted the interest of many researchers, and they have great potential as power batteries for electric bicycles and electric vehicles.

With the depletion of this non-renewable mineral resource, and the positive electrode material accounts for 40% of the total battery cost, if the heavy metals such as cobalt, nickel, and lithium in the positive electrode material are effectively recovered, waste can be turned into treasure, and materials can be recycled. It can alleviate the crisis of mineral resources and achieve sustainable development, and it will also bring huge economic benefits.

3. Recycling of anode materials

There are many types of lithium battery anode materials: ① metal materials, such as lithium metal. ② Inorganic non-metallic materials, mainly carbon materials, silicon materials and other non-metallic composite materials. ③ transition metal oxides. At present, carbon, graphite and non-graphite carbon materials are widely used. Lithium titanate can also be used as a negative electrode material in electric vehicles due to its excellent cycle life, safety and rate performance. The main disadvantage is that it will reduce the energy density of the battery. There are also some companies that have developed tin alloys as anode materials, but they are still in the research stage and have fewer applications. The conductive current collector uses electrolytic copper foil with a thickness of 7-15 μm, so the copper (about 35%) in it can be recycled, and the carbon powder adhering to it can also be recycled as an additive for plastics, rubber, etc. Therefore, it is first necessary to effectively separate the negative electrode constituent materials of waste lithium batteries to maximize the resource utilization of waste lithium batteries.

The mutual peeling between carbon powder and copper foil is effectively realized through hammer vibration crushing, and then the copper foil and carbon powder are initially separated by vibrating sieve according to the size difference and shape difference between particles. Copper foil is enriched in the particle size range greater than 0.250 mm and carbon powder is enriched in the particle size range less than 0.125 mm, which can be directly recycled according to the particle size.

For the crushed particles with a particle size of 0.125-0.250 mm, the effective separation between copper and carbon powder is achieved by airflow separation. The resource utilization of metal copper and carbon powder in the anode materials of waste lithium batteries can be realized through the combined process of hammer vibration crushing, vibration screening and air flow separation.

4. Recovery of organic electrolyte and separator

Most of the electrolytes of digital waste lithium-ion batteries are not recycled, and they are usually burned by fire; while the electrolyte of lithium-ion batteries as a power source accounts for about 15% of the battery cost, and contains rich

Rich lithium ions have higher recovery value. Moreover, the currently commonly used electrolytes generally use LiPF6 carbonate organic solutions. In humid air, LiPF6 will react with water to generate harmful gas hydrogen fluoride. It can be seen that effective recovery of electrolytes can not only reduce harmful gas emissions, but also has certain economic benefits. benefit. The diaphragm of the lithium battery has a microporous structure, which can prohibit the passage of electrons and allow lithium ions to pass through freely. A part of the electrolyte is dispersed in the gap between the electrode and the diaphragm, so the diaphragm is recycled.

After the electrode and diaphragm are immersed in a suitable solvent for a certain period of time, the electrolyte will completely come out and enter the solvent. Polycarbonate (PC) has a large relative dielectric constant, which is conducive to the dissolution of lithium salts. Tong Dongge, Lai Qiongyu, Ji Xiaoyang, etc. soaked the electrolyte and separator in PC solvent for a period of time, and the recovered electrolyte LiPF6 can be reused in batteries.

A Canadian company used low-temperature technology to reduce the relative activity of each component in the electrolyte, and then neutralized the electrolyte with NaOH solution to realize the recovery of lithium battery electrolyte.

The above is the relevant introduction about lithium-ion battery recycling. SUNY GROUP has taken a leading position in the industry in the research and development and manufacturing of lithium-ion battery recycling equipment. At present, it has many cooperative customers in India, South Korea, Vietnam, Japan, Europe and the United States. , if you have related needs, please leave a message and contact us.