How recyclable are batteries from electric cars?

Electric cars produce zero emissions as they drive around, but how environmentally friendly is the production and disposal of their batteries? Vicky Parrott investigates

Batteries

Electric cars are The Future. We all know it. Sales of pure electric cars rose by nearly 14% in 2018 compared to 2017, while hybrid and plug-in hybrids rose by more than 20%. 

This is an environmental and air quality win, no doubt – especially as mains electricity is gets greener every year, but there is an environmental burden that often causes concern: the batteries. 

If every new vehicle sold in 2040 is a plug-in vehicle, it could equate to around 2.5 million battery packs that will need to be reused or recycled. 

These batteries – most of them lithium-ion – typically last around 10 years before losing enough performance that most would consider replacing them. So how recyclable are they, and what are the options other than recycling?

Nissan energy storage

Well, one popular solution is to re-use them as power storage for domestic and commercial buildings. Nissan recently launched the largest power storage facility in Europe to use both new and used car batteries; the Johan Cruyff Arena in Amsterdam (above) uses 63 second-hand EV battery packs and 85 new battery packs, which feed off of 4,200 solar panels on the stadium roof. 

This doesn’t mean that the stadium is off grid, although it is capable of powering the entire venue during an event for up to an hour (the equivalent of providing energy for 700,000 domestic homes) if necessary. Rather, Nissan’s battery-powered energy storage system acts as a generator that can back up the stadium’s energy supply during times of heavy power usage, reducing the strain on the grid at peak times. 

Nissan also offers an off-the-shelf home or commercial energy storage unit, called xStorage (below); a rival to Tesla’s Powerwall 2 system, Nissan’s system is different in that you can choose to have new or second-hand EV batteries. 

There’s an appealing circuitousness to the situation, if used electric car batteries can provide a home energy solution to solve the potential issue of increased car charging putting too much strain on the mains power grid at certain times.

Nissan energy storage

Even so, static energy storage is no one-shot solution for where the redundant electric vehicle batteries will go. Some don’t think it’s a viable solution at all.

Batteries for electric vehicles need to provide a lot of energy in a small package, which requires fairly large quantities of cobalt in lithium-ion batteries. But energy storage units in buildings don’t need to be so small and lightweight, so it’s a common argument that the precious metals of lithium and cobalt are better recycled for more transport applications.

Cobalt production is a critical issue for battery production and the future of electric mobility. Much of it is currently mined in the Democratic Republic of Congo, where the process raises serious ecological, ethical and human rights concerns, so reducing dependency on it as demand for batteries rise is one of the greatest challenges. 

Dr. Gavin Harper, a Faraday Institution Research Fellow at the Birmingham Energy Institute’s project on Recycling and Reuse of lithium-ion batteries (ReLiB), stated that “if we face constraints around cobalt, some feel we should focus this precious resource on more demanding applications such as EVs. It may make more economic sense to recycle EV batteries for use in brand new batteries for cars, rather than using them in a used state in a less demanding application [such as power storage].”

Mercedes power storage

Mercedes-Benz would agree. The German manufacturer launched a home energy storage system (above) using batteries from its range of EVs in April 2017, but the product was axed only a year later, with the company claiming that “it’s not necessary to have a car battery at home: They don’t move, they don’t freeze, it’s overdesigned.” So, for Mercedes-Benz at least, the costs didn’t add up. 

Nissan, however, is adamant that EV battery tech is transferrable for home energy use. A spokesperson stated that Nissan “is committed to operating in the energy services market and is strongly placed to utilise both new and second life EV batteries for energy storage in a way that is commercially viable.”

Another huge consideration is the recycling process. Belgium-based company, Umicore, is one of the businesses already offering recycling for lithium-ion batteries. It reclaims the valuable metals using a combination of pyro- and hydro-metallurgy, and while the company currently runs a pilot plant, it can still recycle around 35,000 EV batteries per year. According to a company spokesperson, Umicore “can easily scale up its recycling activities when the market grows, which we expect to happen in 2025.”

Even better, metals are infinitely recyclable, so they can be reclaimed from used batteries and to produce new batteries that are as good as any other.

Tesla Supercharger

Tesla plans to recycle its batteries to the point where it hopes that the reclaimed materials would negate the need to mine new metals. Tesla CTO, JB Straubel, said that Tesla is “developing more processes on how to improve battery recycling to get more of the active materials back. Ultimately, what we want is a closed loop that reuses the same recycled materials.”

Changing battery tech is another big factor. One hope for the future is sodium-ion batteries, which operate in much the same way as lithium-ion and are similarly recyclable. Sodium is cheaper and far more abundant than lithium, so if sodium-ion batteries can be brought up to the same performance levels as li-ion it could be a no-brainer. 

Solid-state batteries are another likely battery tech of the future, as they’re much less flammable and potentially even more efficient than current lithium-ion cells. BMW, Dyson and Toyota are just some of the manufacturers who have stated that they’ll be using solid-state batteries in the near future. But how recyclable are solid-state batteries?

According to Peter Slater, Professor of Materials Chemistry and Co-director of the Birmingham Centre for Energy Storage, the recyclability of solid-state batteries “would present different challenges in terms of separating the components. In particular, it is likely that it would need chemical separation routes, such as those being developed through the Faraday Institution’s ‘ReLib’ project.”

Ultimately, if the appalling environmental ramifications of putting batteries into landfill aren’t persuasive enough, the cold reality is that the metals they contain – regardless of the cell tech involved - are too valuable to waste. 

In the end, there will be many and varied answers to the question of “what do we do with used electric vehicle batteries?” The good news is that ecological and economic good reason are unanimous on one thing: don't put them in the ground.