Lithium Battery Recycling
Description
Lithium battery recycling is a rather complex process,it can no longer be used when their lifespan comes to an end,the following are its general steps and key points:
1.Collection and classification
1.1 Collection channels
Cooperating with battery manufacturers, electronic equipment manufacturers, used battery recycling stations, environmental sanitation departments, etc., a wide recycling network is established to collect various used lithium batteries,for example, cooperate with mobile phone manufacturers to recycle the used mobile phone batteries replaced by their users.
1.2 Classification
Batteries are classified according to their types (such as lithium cobalt oxide batteries, lithium iron phosphate batteries, etc.), specifications, shapes, and sources of recycling. Different types of lithium batteries may vary in recycling methods and processes,classification helps to enhance recycling efficiency and the utilization rate of resource recovery.
2.Pre-treatment
2.1 Discharge treatment
Prevent safety accidents such as short circuits and fires from occurring during subsequent processing,special discharge equipment can be used to discharge the battery power below the specified safe voltage,for instance, for some large capacity power batteries, an intelligent discharge cabinet can be used for constant current discharge.
2.2 Disassemble
Disassemble the battery pack into individual cells and remove non-battery parts such as the battery casing and connecting wires,this process requires the use of professional disassembly tools, such as electric screwdrivers and hydraulic shears, and at the same time, it is necessary to pay attention to avoiding secondary damage to the battery.
2.3 Crushing
Further break the individual batteries into smaller particles for subsequent processing,crushing equipment usually adopts hammer crushers, jaw crushers, etc,by controlling the crushing force and time, the battery particles can reach the appropriate particle size.
3. Battery Recycling of valuable metals
3.1 Physical method
Magnetic separation: It uses magnets to separate magnetic metals such as iron and nickel from the crushed materials. For instance, through the magnetic field effect of the magnetic separator, magnetic metal particles are adsorbed onto the drum of the magnetic separator, thereby being separated from other non magnetic materials.
Screening: Classification and screening are carried out based on the size of the material particles,the crushed battery materials are screened into parts of different particle sizes through screens of different apertures, so that they can be processed separately later.
Gravity separation: By taking advantage of the density differences among various metals and materials, they are separated through the force of gravity,for instance, in shakers or heavy medium separation equipment, metal particles with higher density will settle at the bottom, while those with lower density, such as plastics and graphite, will be carried away by water or air flow.
3.2 Chemical method
Acid leaching: The pre-treated battery materials are mixed with acid solutions (such as sulfuric acid, hydrochloric acid, etc.) to dissolve the valuable metals (such as lithium, cobalt, nickel, etc.) in the acid solution,to enhance the leaching efficiency, it may be necessary to add some catalysts and control the reaction conditions such as temperature, time and acidity.
Extraction: Selectively extract valuable metals from the acid leaching solution using an extractant,for instance, by using extractants such as tributyl phosphate (TBP), metals like cobalt and nickel can be extracted from acid leaching solutions and separated from other impurities.
Precipitation: Add a precipitating agent to the solution after extraction to precipitate valuable metals in the form of hydroxides, carbonates or oxalates, etc,for instance, adding sodium hydroxide solution can cause lithium to precipitate in the form of lithium hydroxide. After steps such as filtration, washing and drying, compound products of lithium can be obtained.
4.Resource regeneration and product production
4.1 Produce battery materials
The recovered valuable metal compounds are further processed to produce raw materials that can be used in the production of lithium batteries, such as lithium carbonate, cobalt hydroxide, nickel sulfate, etc,these recycled materials can be reintroduced into the manufacturing process of lithium batteries to achieve the recycling of resources.
4.2 Other applications
In addition to producing battery materials, some of the recycled metals and materials can also be used in other fields,for instance, recycled metals such as copper and aluminum can be directly sold to relevant metal processing enterprises for the production of products like wires, cables and auto parts,recycled plastics can be modified and used to manufacture plastic containers, electronic product casings, etc.
5.Safety and environmental protection measures
5.1 Safety management
At every stage of lithium battery recycling, it is essential to strictly follow safety operation procedures and be equipped with necessary safety protection devices, such as fire prevention, explosion prevention, gas masks, and protective gloves,at the same time, regular safety training and emergency drills should be conducted for employees to enhance their safety awareness and emergency response capabilities.
5.2 Environmental protection treatment
Effective treatment and disposal should be carried out for pollutants such as wastewater, waste gas and waste residue generated during the recycling process,wastewater needs to be purified and treated to meet the national discharge standards before being discharged,waste gas needs to be treated by purification equipment to remove harmful gases and particulate matter from it,waste residue should be collected and treated in a classified manner,for waste residue containing harmful substances such as heavy metals, it should be disposed of in accordance with the management requirements for hazardous waste to prevent environmental pollution.
6.Conclusion
Lithium battery recycling requires professional technology, equipment and qualifications, while strictly abiding by relevant laws, regulations and safety and environmental protection standards. Without relevant professional knowledge and experience, it is not recommended that individuals or unlicensed enterprises carry out lithium battery recycling and processing.