The evolution of battery recycling

With the increasing use of portable electronic devices, battery-powered tools and electric vehicles, batteries are more popular than ever, and so is the desire to recycle them. Humans have begun to take notice of their impact on the environment, which has led to an increased focus on recycling and safe, sustainable treatment of end-of-life batteries.

On top of that, the materials used in lithium-ion batteries could potentially be in short-supply soon, as supply chains struggle to keep up with the ever increasing demand. Effective recycling methods could potentially provide a source of materials for new batteries.

In some countries batteries are still largely discarded as household waste, while in others over 65% of domestic-use batteries end up recycled.

A new regulatory framework

Battery recycling has long been governed by minimum targets — a floor percentage of batteries that had to be collected and recycled. That approach is now evolving significantly. Under EU Regulation 2023/1542 of the European Parliament and of the Council of 12 July 2023, the bar is being raised both in scope and ambition.

Overall recycling efficiency targets are increasing: by 2025, at least 75 % of lead-acid batteries and 65 % of lithium-based batteries must be recycled. By 2030, those figures rise to 80 % and 70 %respectively.

But perhaps the most significant shift is the move beyond overall recycling rates. The new regulation introduces material recovery targets for specific critical metals.

Material	By 2027	By 2031
Cobalt	90%	95%
Copper	90%	95%
Nickel	90%	95%
Lead	90%	95%
Lithium	50%	80%

These targets reflect the growing recognition that the materials inside batteries are critical resources. As demand for these metals continues to outpace supply, the regulatory pressure to recover them efficiently will only increase.

Recycling the old and the new

While some older batteries, such as lead-acid ones commonly found in cars, are already recycled with great efficiency, as their construction is straightforward and the technology to recycle them relatively simple, the technologies to recycle other more recent types of battery are still being optimised as their structure and chemistries are more complicated. As new battery chemistries are developed, new technologies will need to be developed to recycle them.

For example, button cell batteries have grown in popularity with more and more miniaturised electronics in our lives. Lithium-ion batteries have become a lot more popular in recent years, particularly with the rise of lithium-cell-powered electric vehicles. This is having an enormous impact on battery production and recycling as we know it. New processes, innovations and regulations are coming into effect to ensure the responsible reclamation of lithium and other valuable resources contained in batteries.

At the same time, other batteries have fallen out of fashion in the last few decades, replaced by better alternatives or phased out of production due to environmental concerns. For example, nickel cadmium batteries are slowly being replaced by nickel metal-hydride, which offers improved energy density and no toxic cadmium. NiMh batteries are in turn also being phased out in favour of lithium-ion batteries for their superior energy density.

Challenges in recycling: built-in batteries

Other than optimising recycle technologies because of more complex battery structures and chemistries, another significant challenge for battery recycling is that many new electronic devices use a “sealed inside” battery rather than a removable component. This is a challenge for future battery recycling as it limits the channels through which a battery can be recycled – with devices requiring specialised dismantling by a skilled technician to remove the battery before it can be recycled.

It is essential that manufacturers pay greater attention to recyclability during the battery design phase. By designing batteries with end-of-life considerations in mind, it becomes significantly easier to dismantle them and recover more materials during the recycling process. This design-for-recyclability approach could substantially improve recovery rates and reduce processing costs.

Shredding vs. disassembly

Current battery recycling methods tend to involve shredding batteries into tiny pieces, which makes it easier to extract certain materials, but also makes subsequent processing more challenging. However, new and future-focused recycling methods make use of automation and robotics for the disassembly of batteries. This could improve safety and efficiency while allowing us to recover battery parts in their entirety, ready to be directly re-used in the production of new batteries.

The need for flexibility

Recycling methods that rely on disassembly will need to be highly flexible in order to process a range of batteries from various devices. Some manufacturers are already developing sophisticated robots capable of dismantling products and batteries for recycling. For example, Apple has demonstrated smart robots that can disassemble their phones for recycling. This is a fine solution for manufacturers who take back their own products for recycling. However, more general recyclers will need to develop more complex and flexible solutions in order to deal with a wider range of different feedstock batteries and devices.

Direct recycling and bioleaching
In recent years, there has been a growing focus on "direct recycling" methods, which aim to work more efficiently, recover more materials, and save energy compared to traditional recycling approaches. These direct recycling techniques preserve the structure of battery materials, allowing them to be reused more directly in new battery production.

Researchers are also developing innovative new techniques such as bioleaching, which uses biological processes to extract valuable metals from batteries. However, these emerging technologies still need to prove their commercial viability and effectiveness at scale.

Did you know... It’s a matter of size

For some types of batteries it’s particularly challenging to improve the recovery rates of materials. Small batteries from mobile devices often end up in general waste instead of appropriate battery recycling channels. For larger electric vehicle batteries recovery rates are much higher due to heavy regulation within the industry, prescribed routes for treating end of life vehicles and effective infrastructures already in place.

How about electric vehicles?

The electric vehicle industry is expected to continue growing dramatically, which means a huge increase in the number (and size) of batteries that need to be recycled in the years to come. This has led to the development of new battery recycling processes, with a particular focus on lithium-ion batteries, as these rechargeable batteries are set to power many modern electrical devices.

Removing these batteries from the vehicle is labour intensive, and once removed they need to be disassembled and the separate modules tested to ascertain whether they can be remanufactured, reused or recycled. This entire process is slow when done manually and there is potential to speed it up through automation and smart robotics.

Recycling electric vehicle batteries

There are some methods for recycling electric vehicle batteries which have been adapted from other processes used in the treatment of waste electrical and electronic goods. Pyrometallurgical processes are attractive due to their flexibility: they can accept a wide range of battery chemistries, sizes and conditions, requiring little pre-sorting or pre-processing. Operating at high temperatures, they safely destroy electrolytes, binders and organics, simplifying downstream processing. They also efficiently recover valuable metals such as cobalt, nickel and copper. However, pyrometallurgy is not optimised towards recovery of all materials — lithium, aluminium and manganese typically end up in a slag form from which they cannot be recovered in an economically viable way.

This is where hydrometallurgy plays a complementary role. Using chemical leaching and separation techniques, it selectively extracts and purifies metals from black mass — including lithium — achieving recovery rates of up to 95 %, in line with EU targets. It can also produce battery-grade materials ready for direct reuse in new battery manufacturing.

In practice, modern recycling plants increasingly combine both approaches: pyrometallurgy for its robustness and flexibility at intake, hydrometallurgy for its precision and maximum material recovery.

What does the future look like?

Battery technology continues to advance with manufacturers developing increasingly sophisticated batteries using less expensive materials. There are now rechargeable batteries available that contain no cobalt, nickel, or lithium. Whilst this represents progress in terms of sustainability and cost reduction, it creates a significant contradiction for the recycling industry: when batteries contain fewer valuable materials, there is less economic incentive to recover them, which increases recycling costs. This paradox presents major challenges for the future of battery recycling economics.

Also, recycling facilities across Europe remain relatively small-scale operations. Looking towards the future, upscaling these facilities and implementing standardisation across the industry will be crucial for reducing costs and improving efficiency. Only through larger, more standardised recycling operations can the industry hope to achieve the economies of scale necessary to make battery recycling economically viable on a continental level.