Recycling Lithium-Ion Batteries

Recycling Lithium-Ion Batteries
05 Okt 2021

Lithium-ion batteries are real all-rounders used in a wide variety of products such as notebooks, smartphones and electric cars. In our blog article entitled Lithium Ion Batteries in Focus, we took a closer look at the technology involved. But what happens to them at the end of their use phase? Does future recycling entail problems for the environment, or can it spawn a new, strong business sector? And how critical is the extraction of the raw materials?

Critical reaction to lithium extraction

The extraction of raw materials for lithium-ion batteries has been the subject of criticism since long before the boom in electric vehicles. Rare earths and minerals, including the key element lithium, are required for the production of such batteries. Lithium salts occur in sea water and, under certain conditions, in inland waters such as the salt flats in the border region of Chile, Argentina and Bolivia. Salt flats are dried-up waters with high concentrations of mineral and salt residues. The extraction of the raw materials in particular presents significant ecological and social challenges. For example, it destroys natural barriers, resulting in the mixing of salt water and potable water, thus contaminating reserves of drinking water in the region. And the extraction of other raw materials used in the batteries is also highly problematic for the environment.

Recycling methods for lithium-ion batteries

Up to 75% of the raw materials in a battery can be returned to the usage cycle, depending on the processing methods and the materials themselves. Researchers believe that, in theory, a recycling rate of 90% is possible, but that will require further development in the technologies involved and optimisation of the process steps. There are currently two different recycling processes:

Mechanical recycling

Mechanical recycling is the conventional approach in which the lithium-ion batteries are first sorted according to the substances they contain and processed in piles. The battery modules then go into a shredder. The shredded material is sorted by magnetic and electrical properties so that the metals are now in powder form and processing can continue.

Pyrometallurgical recycling

Due to the raw materials‘ different melting points and densities, phases occur in which the metals can be easily separated, thus enabling the extraction of a high percentage of material. Other components such as plastic, halogens or other materials are separated from the battery in thermal processing.

Critics are unhappy with the huge energy requirement of the pyrometallurgical process, and in most cases more CO2 is emitted during recycling than during the manufacture of a new battery. Moreover, the yield in raw materials is very low compared to the energy requirement, and the processes are enormously complicated, slow and susceptible to malfunctions. However, one advantage is the ability to assign priorities to the extraction of raw materials. For example, it is possible to regain up to 95 percent of the cobalt.

Perspectives regarding the recycling of lithium-ion batteries

In future it is likely that repairs will extend battery lifetime so they can be used for twice as long. However, as soon as battery performance begins to decline, it is high time to think about recycling the materials used.

Due to the critical situation requiring the procurement of raw materials, as much raw material as possible needs to be recovered from batteries – and the method should be as sustainable as possible.

Despite the many and varied fields of application, there are currently so few batteries that one can hardly speak of an economic benefit from recycling. Due to low capacities, there are currently no large-scale, profitable recycling processes. However, there is a very good chance that recycling will become profitable for companies at some point in the future, both in terms of the energy footprint and from a commercial point of view. However, large volumes are essential for this scenario.

The laws and regulations governing electronic waste already oblige every manufacturer to dispose of or recycle its products. However, this currently represents an additional cost factor for producers. But as sales increase, it is conceivable that recycling capacities for batteries will be increased and evolve into a profitable industry.

Summary

The procurement of raw materials and the recycling processes for lithium-ion batteries are not always clean and are currently the cause of a large number of problems. In future, batteries should be used that do not depend on critical raw materials or rare earths. Sodium, for example, could be a possible alternative – a raw material that is more common and less costly to extract.

There is also a noticeable trend towards lithium-ion batteries in solar power systems. They are flexible in terms of size and don’t have to deal with the restrictions that apply to electric cars. Furthermore, their design is less complex and other technologies can also be used more easily.

A further promising approach is represented by batteries that lend themselves to repair and therefore remain in the usage cycle for longer. A very long life cycle is always the most sustainable option.


Lisa Neulichedl