Did you know that battery recycling conserves natural, finite resources such as lithium, cobalt and nickel?
Batteries, including those used in electric vehicles and mobile devices, are also recycled to prevent the release of hazardous substances (e.g. lead, cadmium and acids) into the environment. Importantly, it takes considerably less energy to extract and refine metals from recycled batteries than it does from mining and processing virgin ores. This helps reduce greenhouse gas emissions and the overall environmental impact.
The recycling process varies depending on the type of battery, but here’s a snapshot of how batteries are typically recycled:
1) Collection
Used batteries are collected from various sources, including recycling centres, electronic waste collection points, retail outlets, car repair shops and manufacturers. It is crucial to keep batteries separate from regular waste to prevent environmental contamination. Certain batteries, particularly lithium-ion batteries, have the potential to catch fire or explode if they are damaged, crushed or punctured. When batteries are mixed with other waste, there is a higher risk of them being damaged during handling or transportation, leading to potential fires or hazardous incidents.
2) Sorting
The batteries are sorted based on their chemistry and type, as different battery chemistries have different recycling processes. The most common types of batteries include alkaline (e.g. AA, AAA, C, D, as used in remote controls, toys, torches and clocks), lead-acid (e.g. used in cars and backup power systems), as well as lithium-ion and nickel-metal hydride (used in portable electronics like smartphones, laptops, tablets, cameras and power tools). The sorting process helps prevent cross-contamination and ensures that hazardous batteries are handled and dealt with safely to protect the environment and the workers involved.
3) Discharge
Before processing, any remaining electrical charge stored within the battery cells must be removed, to ensure safe handling during the next steps. Having said that, not all batteries can be fully discharged due to their chemistry or design. In such cases, special precautions must be taken to handle and process these batteries safely.
4) Mechanical shredding
The next stage involves the batteries being shredded into small pieces using specialised equipment. The aim is to break down the batteries into smaller components, such as metals, plastics and other materials.
5) Processing the shredded components
This step depends on the battery type.
Lead-acid batteries, for example, undergo a hydrometallurgical process called ‘leaching’. This involves submerging the shredded components in sulfuric acid or another chemical solution to dissolve and recover the lead, so it can be used to make new batteries or other products.
Lithium-ion batteries, on the other hand, undergo a pyrometallurgical process called ‘smelting’. Here, the shredded battery components are heated in a furnace to a high temperature, which separates the metals from other materials. This process recovers metals such as cobalt, nickel, lithium and copper.
Advanced recycling methods for lithium-ion batteries involve electromechanical processes (hydrometallurgical and direct recycling techniques), where valuable materials, such as cobalt, lithium and nickel, are recovered directly from the electrode materials through solvent extraction, precipitation and/or electrowinning. This eliminates the need for smelting.
6) Refining and purification
The recovered metals may undergo additional refining and purification processes to meet the required quality standards for reuse in battery manufacturing.
7) Recycling of other materials
Apart from metals, batteries may contain other valuable materials like plastics and electrolytes. These materials can also be recycled or used for various applications.
8) Responsible disposal
Any remaining waste or hazardous substances that cannot be recycled are disposed of in accordance with environmental regulations and guidelines.
Battery recycling is vital for conserving natural resources, reducing the environmental impact and promoting the circular economy, where materials are reused to create new products. This therefore minimises the need to mine for raw materials. As battery technology advances and recycling methods improve, this whole process is likely to become more efficient and sustainable.
Help us give your old batteries a proper farewell! Never put them in a skip – even if they’re tiny – take them to a dedicated collection point instead. Together, we can make a world of difference.