For electric mobility to be truly sustainable, battery recycling still has some way to go. Nevertheless, signs of promise are beginning to grow.

Covid-19 may have hit car manufacturers hard, but amid the struggles, there has been a chink of light as electric vehicle (EV) sales continue to increase. 2020 saw global year-on-year growth of more than 40 per cent – a rise that shows no signs of slowing. According to the International Energy Agency, there could be more than 230 million EVs on the roads by 2030 – a huge leap from just over 10 million today.

While this will drastically reduce tailpipe emissions, it does present two major challenges: making enough batteries and recycling them at end of life – especially with the simultaneous growth in other electric mobility like scooters and bikes.

Raw materials such as cobalt, lithium and nickel are key ingredients for lithium-ion batteries. The mining of these materials can present serious ethical and environmental concerns, including reports of child labour, pollution and heavy water use. What’s more, the materials are finite: supply may struggle to meet future demand.

That makes recycling all the more important. Currently, however, the recycling rate for EV batteries is extremely low, with some estimates putting it at five per cent. For electric mobility to represent a truly sustainable solution, this needs to change.

Battery recycling: How it works

Manufacturers typically guarantee an EV lithium-ion battery for seven to eight years, or 100,000 miles of use, although they often last longer. Rather than reusability, they have traditionally been built for performance and durability. EV batteries are large and heavy, comprising several hundred individual cells, all of which need dismantling. However, most components are welded together, which is good for electrical connection, but bad for efficient recycling. It can also be dangerous work: cut into the wrong place and a battery can short-circuit, combust and release toxic fumes.

But things are changing. The latest EVs now have solid-state batteries, which are smaller, less complex and not as flammable. Meanwhile, the new Blade battery, from Chinese firm BYD, is expected to raise the bar even higher in terms of performance, safety and recyclability – thanks to its modular design.

Traditionally, lithium-ion battery recycling relies on two techniques: pyrometallurgy and hydrometallurgy. For the former, which is more common, recyclers shred and then burn the batteries, before extracting the metals. In hydrometallurgy, batteries are dissolved in acid, leaving a metal “soup” ready for extraction. Neither is ideal: pyrometallurgy is energy-intensive, while the alternative uses potentially harmful chemicals.

Building a circular battery industry

The EV battery recycling market is currently a small one, comprising around 100 companies worldwide. But it is growing fast. Some, like Sweden’s Northvolt, combine battery recycling with manufacturing. Founded by Tesla’s former supply chain head, it was recently valued at almost $12 billion and has racked up orders worth a reported $27 billion. The company is currently building a huge 500,000-square-metre factory in Sweden as part of its plan to create a “circular European battery industry”.

Other companies focus solely on recycling. In the United States, another Tesla alumnus, co-founder and former CTO JB Straubel, has set up Redwood Materials. The company takes e-waste from a variety of industries before sending repurposed materials to battery makers like Panasonic. It, too, has already reached a multi-billion-dollar valuation.

German firm Duesenfeld, meanwhile, is a dedicated lithium-ion battery recycler. It uses a patented method that combines mechanical, thermodynamic and hydrometallurgical processes to extract high-quality recycled materials from batteries. This is important: some recycled battery metals are only suitable for use as ”inferior” materials in areas like construction, but Duesenfeld says it can deliver battery-ready secondary raw materials.

Giving batteries a second life

Not all used batteries are redundant once they are removed from an EV. Although they may no longer be able to power a vehicle, many still have sufficient capacity for other functions. Nissan and Volkswagen, for example, are now reusing old EV batteries in some of their factory robots.

Other batteries are being repurposed by “upcycling businesses” like Betteries. The German company uses second-hand EV batteries to power fishing boats or as mobile power units for remote locations. Solving this problem will require vehicle manufacturers, battery makers and third parties to work hand in hand.

Further impetus to change will undoubtedly come from legislation. China already has incentives for manufacturers to source recycled over virgin materials. Europe is set to introduce stricter recycling requirements in the next couple of years and, although the US is yet to propose any concrete changes, they may soon have little choice but to follow suit.