Global consumption of lithium and cobalt is growing significantly faster than production due to strong demand for lithium-ion batteries for the automotive industry. It is often argued that the recycling of old batteries will make up for some of the difference, but recycling is a complicated, energy-consuming and more efficient procedure for recovering cobalt than lithium. In addition, global capacity remains very limited. An article written by a team from the Chinese Academy of Sciences takes stock.

One of the first obstacles to recycling is that lithium-ion batteries (BLI) are a dangerous material, to handle with care. Residual electrical power can cause fires or explosions. The electrolyte reacts easily with water to produce toxic gases such as hydrogen fluoride. Lithium deposited on the anode can also react with water to produce hydrogen and lithium hydroxide, a powerful caustic agent. Finally, metals such as cobalt, nickel and manganese can pollute water and soil. From Manta Kinsbursky Brothers you will have all round supports available now.

In addition, there are currently a large number of variants of the BLI, distinguished mainly by the content of the cathode, and known as the component substances. LiCoO2, LiNiO2, LiFePO4 and lithium nickel cobalt manganese (NCM) batteries as well as lithium nickel cobalt aluminum (NCA) are particularly distinguished. These different batteries are not always well identified and yet, each requires a recycling method a little different.

Approaches to separation of metals

There is a wide variety of approaches to recycling the content of batteries, each with advantages and limitations. Manufacturers typically use a combination of physical and chemical methods to recover BIL content. Physical methods include dismantling, crushing and sieving batteries, and applying heat treatments. Chemical methods fall into several categories:

Pyrometallurgical processes involve heating the residues at high temperatures to separate the metals as slag or alloys. They are energy intensive, requiring temperatures of up to 1475 ° C for 30 minutes. Very effective at separating cobalt, nickel and copper, they allow half of manganese and almost all lithium to pass through.

Hydrometallurgical processes rely on the use of liquid phase reagents to dissolve or precipitate metals. Traditional leaching uses strong acids as solvents, but there are also methods using alkalis. The alkaline method is very effective in separating cobalt, copper and nickel, but less so for other metals.

Biometallurgical processes use microorganisms to transform insoluble substances into soluble products, which can then be separated by other methods. These are energy-efficient processes, but can take up to a week and only work with very low concentrations of material to recycle, which limits their usefulness. Recovered material rates are also too low to ensure profitability.

There are also methods using solvents and others seeking to cause precipitation by the use of various additives.

In general, recycling companies use a combination of physical and chemical approaches and focus on hydrometallurgical approaches to the extent possible because of their lower energy cost. About fifteen different processes are used around the world. It is therefore important to avoid talking about the recycling of BLIs as if it were a single process, applying to all batteries.

 

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