What happens to old EV batteries?

Saturday, 18 September 2021

There are simply too many valuable resources in old EV batteries to just throw them away.

The environment is becoming a key focus in ‘circle of life’ production for most industries these days, and arguably none more so than in automotive manufacture.

From the power source of the factory, through the use of recycled materials and then on to end of life reuse, carmakers are squeezing virtually every last drop out of each and every vehicle component, and that includes EV batteries.

It takes a lot of power to run an electric vehicle, in fact, on average an EV consumes around 0.20 kWh/Km. It’s a tough application for rechargeable batteries too with huge power draws followed by hefty charging regimes and over time, even using ‘by the book’ best practice recharging, at some point the lithium-ion batteries will degrade (approximately a decade), but don’t think all is lost for our multi-celled friend.

There is a misconception that in years to come, our landfills will be awash with toxic battery waste leaking into the earth and soiling our beautiful blue planet. But thanks to ‘second-life’ opportunities and the desirable materials EV batteries are actually made from, the landfill option is actually the least attractive one. So what are the other options?

Battery refurbishment

Not all EV batteries are constructed the same way and there are some battery modules that, provided they have minimal degradation and are defect or damage free, can be refurbished and reused directly as a replacement for the same model vehicle. Major automakers are offering rebuilt or refurbished battery packs for purchase or warranty replacement of original battery packs in EVs.

Second-life application

Renault uses ‘second life’ batteries to power a number of its facilities.

When an EV battery reaches the end of its useful first life, (about 70 to 80 per cent of its capacity), they’ve still got more than two thirds of their usable energy storage, which means that there is still more than enough power to store the likes of solar-generated energy for home or office (or even camping) use, and some car-makers themselves are using second-life batteries to power their facilities and other operations.

Depending on their condition, it is believed that used EV batteries could deliver an additional five to eight years of service in this secondary application.

Volkswagen has recently started a battery recycling pilot programme.

For the consumer, (even without solar panels) the ability to pick off-peak power rates to charge their EV battery storage will see a significant power bill reduction and for energy supply companies, EV energy storage cells could even negate the need to build additional power plants.

It’s believed that with the rapid rise of EVs (and the even faster expected growth over the next ten years) the second-life-battery supply for stationary applications could exceed 200 gigawatt-hours per year by 2030.

Technology does exist to shred lithium-ion batteries to recycle the metals.

Recycle - the sum of all parts

Production of an EV battery requires many raw materials, and they currently include carbon, graphite, metal oxide, and lithium salt and electrolyte liquid, gel or polymer. Often these cells will be created in a cylindrical shape with the cathode and anode produced as sheets (with a separator in between), then filled with the electrolyte material. These cylindrical cells are linked together to carry the charge and arranged as a ‘module’. Multiple modules will then make up an EV battery ‘pack’.

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Obviously, the opposite is required to dismantle and recycle, but unlike production, it’s not exactly an automated process. So is it worth it? Well, yes, it is.

Dismantled parts of the battery systems such as aluminium and copper are simply given to established recycling streams, however, the industry as a whole is still working out the best way to recycle the EV variant of lithium-ion, particularly at scale.

Currently, a lot of the battery is reduced during the recycling process to what is called ‘black mass’ which is a mixture of lithium, manganese, cobalt and nickel. This does however, still require a further, energy-intensive process to recover the materials in a usable form.

Manually dismantling the fuel cells allows for more of these precious materials to be efficiently recovered, but this brings about problems of its own in terms of health and safety and labour costs.

But make no mistake, recycling is still a serious option, particularly as prices for precious metals such as lithium, cobalt, manganese and nickel have risen considerably over time.

Several carmakers have announced battery recycling plans, with one recently opening its first recycling plant and currently plans to recycle up to 3,600 battery systems per year during the pilot phase.

As with the vehicles themselves, the recycling ethos will (in time) be more prevalent and this in turn will reduce the need to mine core materials and make the EV battery ‘circle of life’ even more sustainable.