July 12, 2020

EVs, batteries and the multi-million-tonne scrap heap

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To say that the legacy of today’s electric vehicles is set to be a mountain of lithium-ion battery waste would be kind. In 2017, when worldwide sales of electric vehicles exceeded one million cars per year for the first time, calculations from UK-based University of Birmingham researchers revealed stark figures. These vehicles alone are destined to leave some 250,000 tonnes of unprocessed battery waste when they eventually reach the scrap heap in 2027. This is just the beginning.

Latest modelling from the Paris-based International Energy Agency indicates the number of electric cars on the road will lie between 125 million and 220 million by 2030. Given this, come the middle of this century, the 250,000-tonne waste figure looks meagre against the tens of millions of tonnes of waste that could follow. And to make matters worse, recycling is playing catch-up.

Right now, lithium-ion battery recycling rates across Europe, the US and Australia typically come in at less than 5 per cent, for one simple reason – it isn’t easy. Every electric-vehicle (EV) battery is home to a wealth of exotic materials that make lead-acid or nickel metal hydride battery recycling look like a walk in the park. While large-scale facilities do exist to recycle the core elements within the lithium-ion battery, the processes cost the Earth in terms of cash and energy consumed.

Yet all is not lost. A growing number of research organisations, start-ups and established companies are rolling out novel methods to retrieve more elements from within the electric-car battery. At the same time, energy businesses are joining forces with automotive manufacturers to find new ways to re-use the aged lithium-ion battery.

More progress is needed fast, but at least for now, the race to find a solution to the problem of lithium-ion battery recycling is well under way.

Solution: Turning over an old Leaf

Not all electric-vehicle batteries are hitting the scrap heap when they’re done in cars. Come the end of the road, when the lithium-ion battery can no longer provide the driving range and acceleration required to power a vehicle, it still holds up to 80 per cent of its storage capability. So, instead of hitting landfill, these spent power packs are re-purposed for a range of less power-hungry applications.

A prime example is the Nissan Leaf electric car battery, which is getting a new lease of life in a home-energy storage system developed by Japan-based car maker Nissan and US power-management firm Eaton. Launched in 2016 and designed to save households electricity and cash, the xStorage Home system was Nissan’s answer to similar systems from Tesla and Mercedes, but with the bonus of using old or ‘second-life’ batteries.

xStorage Home connects 12 past-their-best Nissan Leaf lithium-ion batteries with a power inverter and control system in a boiler-sized unit. Once installed in a home, this system connects to the public power grid so it can charge up at night when electricity is cheaper. This nice stash of electricity can then be used during the day when energy is more expensive, or even sold back to the grid, saving the household money.

The storage system can also plug into a home’s own power supply, say a wind turbine or solar panel array. It will then store the energy generated during the day and use this to charge electric vehicles at night.

In the last four years, thousands of systems have been installed in homes across Europe. For example, the Solvang Housing Association in Norway relies on three storage systems, while some 20 systems are scattered across coastal Rogaland, also in Norway. Additional intriguing examples include what Nissan calls the most remote music studio in the UK, at Black Bay in Stornaway, Scotland, as well as an eco-friendly independent cinema, Lexi, in London.

Yet perhaps the most spectacular xStorage installation to date resides at The Netherlands’ largest stadium, the Johan Cruijff Arena in Amsterdam. Here, 148 re-used and new Nissan Leaf batteries have been installed to deliver a mighty 3MW of uninterruptible back-up power for events.

Solution: Joining the grid

Nissan and Eaton are not the only companies using second-life electric vehicle batteries to build storage systems for homes and other buildings. Back in 2017, UK-based Powervault joined forces with Renault, as well as Nissan, to reuse Renault Zoe and Nissan Leaf batteries in its energy-storage units.

Fast-forward three years and the refrigerator-sized battery packs – called Powervault 3eco – are rolled out in hundreds of homes, as well as schools, across England. Talks are also under way to take the power packs to the rest of Europe.

At the same time, Powervault has been trialling its cutting-edge battery technology with UK Power Networks, an electricity distribution network operator covering southern and eastern England, including London. Here, households have been storing energy in battery packs, which the network operator draws on when needed to boost flexibility in the local electricity network, shift energy demand away from peak times and reduce the need for new substations and cables.

Further afield, the company has hooked- up with Japan-based JXTG Nippon Oil & Energy Corporation to also work out how its storage units can best balance the power peaks and dips in Japan’s electricity grid.

As Powervault chief executive Joe Warren says: “Our vision is that Powervault will become as commonplace as a washing machine or dishwasher, allowing zero-carbon energy to be stored at home for when it’s needed most.”

At the same time, Sweden-based Box of Energy has used battery modules recovered from old Volvo hybrid cars in its energy-storage systems to power homes.

And Relectrify, an Australian developer of advanced battery control systems, is integrating spent electric batteries from Volkswagen and Nissan vehicles into its battery-storage systems.

Only this year, Relectrify launched its super-sized ‘BMS+Inverter’ system, currently used in a grid storage pilot with Nissan North America and America Electric Power. The company says this represents an engineering breakthrough, providing a very high-efficiency grid-compliant AC output by orchestrating a vast number of individual cell voltage contributions within a battery pack.

The company has also joined forces with New Zealand-based electricity and gas supplier Vector to connect its systems to the grid and power homes.

Solution: Convenient energy

Not one to be left behind, Japan-based Toyota has been installing used Prius hybrid batteries at 7-Eleven convenience stores in Japan, to store the energy generated by solar panels. This energy is being used to power drinks refrigerators, fried chicken ovens and sausage grills inside the stores.

These batteries, alongside stationary fuel-cell generators, are centrally controlled by building energy-management systems to raise the use of renewable energy and electric power derived from hydrogen. Small fuel-cell trucks are also being used to deliver goods to the stores.

Solution: From old to new

In its ongoing bid to reuse and recycle electric-vehicle batteries, Nissan teamed up with Japanese conglomerate Sumitomo to set up Japan’s first lithium-ion battery reuse and recycling plant in Namie, Japan, back in 2018.

Operated by joint Nissan-Sumitomo business 4R Energy, the plant is removing battery modules from Nissan Leaf electric-car batteries with dwindling energy capacities. These are then re-assembled to form new battery packs.

Crucially, 4R Energy has developed a system to swiftly measure the performance of used batteries which can test them at the Namie plant.

The facility can process more than 2,000 batteries a year, with the best-performing modules used in replacement Leaf batteries.

Meanwhile, lesser modules will be reassembled and used in batteries for electric fork-lift trucks, golf carts and street lights.

Solution: Bringing light to dark times

There is more to Namie – the location of Nissan’s lithium-ion battery re-use and recycling plant – than meets the eye. The Japanese town was abandoned in 2011 after the devastating earthquake and tsunami that triggered a meltdown at the Fukushima Daiichi nuclear power station some 5km away.

Residents returned in 2017 and, given this, Nissan has been working with 4R Energy to create a new type of outdoor LED light that operates without power from the main grid. The Leaf batteries currently processed at Nissan’s re-use and recycling plant are proving instrumental here.

The Reborn Light project aimed to provide public lighting with a new outdoor streetlight using solar panels to charge up a Leaf battery located within its base. The battery can then power the light at night.

As Nissan puts it: “Even when batteries no longer serve to power cars, they can be reborn to keep serving humans.”

Solution: State-of-the-art recycling

Breathing new life into old batteries is not always going to be enough. A lithium-ion battery is made from lithium, cobalt, nickel and other scarce metals that must be mined and extracted, putting a strain on the world’s supply of these elements. Recycling batteries to extract these precious materials for re-use is clearly critical but isn’t easy.

While many large pyrometallurgy or smelting plants can recover cobalt, nickel and copper from lithium-ion batteries, the processes are expensive, energy-intensive and can’t extract other important materials.

However, a handful of state-of-the-art plants have now emerged to tackle the problem with more eco-friendly processes. For example, electronic waste recycler TES has opened two new battery-recycling facilities in Singapore and France that recover elements using mechanical and hydro-metallurgical methods.

Each site uses auto-punching machines and shredders to break batteries down into fine substances, while in a solution. Once dry, magnetic separators recover copper and aluminium. A chemical treatment process is used to recover cobalt and lithium. Crucially, the process does not release heavy metals or volatile organic compounds into the atmosphere.

In a similar vein, German start-up Duesenfeld shreds batteries under inert nitrogen, with the flammable electrolyte being pumped out, evaporated and condensed. Dry materials are then separated by operators based on size, weight, magnetism and electric conductivity. During the process, cobalt, copper, nickel, lithium, manganese, aluminium, graphite and, of course, the electrolyte are recovered.

Other key processing facilities include Akkuser in Finland, American Manganese and Battery Resourcers in the US, Li-Cycle, Canada, and Retriev, based in Canada and the US. Crucially, recycling at such facilities reduces CO2 emissions and can recover more materials than traditional processes.

Duesenfeld, for one, claims that its process saves 4.8 tonnes of CO2 per ton of recycled batteries relative to more traditional processes, and recovers 91 per cent of a battery’s materials compared to just 32 per cent for pyrometallurgical processes.

Solution: Future hopes

A flurry of research projects are also under way worldwide to take lithium-ion electric-vehicle battery-recycling processes to higher efficiencies and lower costs.

In early 2019, the US Department of Energy launched a $5.5m Lithium-Ion Battery Recycling Prize and invested $15m into a new lithium-ion-battery-recycling centre, ReCell, housed at the Argonne National Laboratory in Illinois.

Through these programmes, researchers across the USA are developing automated battery-sorting methods, designing batteries for disassembly, and inventing new processes for recovering all metals inside the cathode.

For example, the ReCell centre – a collaboration of universities and three national laboratories – is developing methods to restore the lithium content of end-of-life lithium-deficient cathodes, so they can be directly re-used in new batteries without using acid or furnaces during processing.

Meanwhile, US auto-battery collection business Clarios, a finalist in the Lithium-Ion Recycling Prize, is hoping to build stockpile locations for lithium-ion batteries and then develop technologies to extract critical materials for new battery production.

In the UK, the Faraday Institution is funding the ReLiB project, which is looking at the best ways to develop a robust technological, economic and legal infrastructure to recycle close to 100 per cent of the materials in lithium-ion automotive batteries.

For example, researchers are using robotics to safely dismantle batteries to recover lithium, cobalt and more.

As part of this, Professor Paul Christensen from Newcastle University is working with UK Fire and Rescue Services to develop protocols for dealing with lithium-ion battery fires. “These batteries still contain huge amounts of power and at the moment we are still relatively unprepared about how we deal with them when they reach the end of their life,” he says. “[We have this] public safety issue that needs addressing as second-life electric-vehicle batteries become more widely available, so we need to look at the battery life-cycle from digging materials out of the ground to disposing of them again at the end.”

Other key recycling projects are taking place at CSIRO in Australia, as well as across Europe with the EU-backed ReLieVe, Lithorec and AMPLiFII.