Otago Daily Times

Rethink battery life spans or we’ll run out of juice

Batteries are the environmen­tal Achilles heel of electric vehicles unless we repair, reuse and recycle them, Mehdi Seyedmahmo­udian, Alex Stojcevski and Saad Mekhilef ,ofthe Swinburne University of Technology in Melbourne, write.

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ELECTRIC vehicle advocates say the cars ultimately have a smaller carbon footprint than their fossilfuel­led counterpar­ts and could resolve our energy concerns for good. Well, fair enough, but questions arise when we dig into the inner layers of electrical vehicles and see how sustainabl­e their components are. In fact, the batteries that power electric vehicles may also be their Achilles heel.

Batteries are the most expensive component of an electric vehicle. If the battery pack is damaged, defective or simply old, this can lead to the vehicle being written off prematurel­y. Tesla is even producing ‘‘structural’’ battery packs described as having

‘‘zero repairabil­ity’’.

Increasing­ly scarce and valuable resources, such as lithium and water, are needed to make these batteries.

Despite this, they are often not designed for ease of repair, reuse or recycling. This has significan­t environmen­tal impacts, ranging from the mining for materials and the water and energy used in making new batteries and vehicles, through to the hazardous waste from discarded batteries.

In other words, the answer to the question of ‘‘Are electric vehicles really ecofriendl­y?’’ largely depends on how we manage the downsides associated with their batteries.

Changes in how we design, produce, use and recycle electric car batteries are urgently needed. These changes can ensure that, in solving the problem of fossil fuel emissions, we also minimise other environmen­tal harms.

Tackle the problems before they get too big

It’s important to resolve these issues now, while electric vehicles make up a small fraction of the global vehicle fleet. Even in worldleadi­ng Norway, only 20% of cars on the road are electric. In Australia, fewer than 100,000 out of 20 million registered vehicles are batterypow­ered.

Yet already we are wrestling with the emerging concerns about their batteries. The performanc­e of lithium batteries in an electric vehicle can degrade to 7080% of its full capacity within six to 10 years, depending on the owner’s driving routine. At that point, the battery is barely reliable as the main energy source of the vehicle. Repeated fast charging can degrade a battery sooner.

Globally, about 525,000 batteries will reach the end of their useful life for powering a vehicle by 2025. That number soars to over 1 million by 2030.

There’s life after EVs for batteries

However, the total lifetime of lithium batteries is 20 years. This means the end of a battery’s usefulness in a vehicle doesn’t necessaril­y mean it has to be discarded. These retired batteries can have plenty of other uses.

So how much capacity does a retired battery still have? As an example, an energy storage made of five repurposed Chevrolet Volt batteries can meet two hours of peakuse energy demand for five houses. The numbers become even more appealing for Tesla Model 3 batteries, which have three times the energy capacity of the Chevrolet Volt’s.

That is a tremendous capacity still available in a retired battery. So why not use that?

And once the battery has reached the end of its useful life, most of the raw materials used to make it can be recovered. It is possible to extract over 95% of the valuable metals like lithium, nickel, cobalt and copper. The European Union already requires electric vehicle batteries to be at least 50% recyclable by weight, increasing to 65% by 2025.

However, the current lack of standardis­ation of battery packs presents a challenge for battery recycling. There are many different physical configurat­ions, cell types and cell chemistrie­s.

Reuse has a long value chain

The good news is that battery reuse is not a fictional utopia. Carmaker Nissan is already doing it on Koshikishi­ma, an island in southweste­rn Japan.

Batteries are recovered from electric vehicles, have their health assessed and then allocated to suitable secondlife applicatio­ns.

These batteries can be reused in a solar farm, as an emergency household power supply, or for an electric forklift in a warehouse. Research shows this repurposin­g of batteries can get another 1015 years’ use out of them. That’s a huge leap towards reducing their environmen­tal impact.

So, who benefits from this scheme? Well, there’s a long list.

In the first row, electric vehicles owners benefit immediatel­y if their used batteries can be sold for a good price.

In the longer run, the list of beneficiar­ies expands massively. Households can enjoy more reliable and cheaper energy simply by charging up their battery storage during offpeak hours for use at peak times when electricit­y costs are higher.

As an initiative in Portugal showed, using repurposed electric vehicle batteries in this way could cut energy bills by 40%.

Reusing batteries is good news for the environmen­t. Research suggests reducing the demand for new batteries in this way could cut greenhouse gas emissions from making batteries by as much as 56%.

The long list of benefits of giving electric vehicle batteries a second life, then recycling their materials, is enticing. Given the scale of the potential economic and environmen­tal gains, along with the countless jobs such work can create, batteries could be more generous in their afterlife than in their first incarnatio­n in electric vehicles. — theconvers­ation.com

 ?? PHOTO: REUTERS ?? An aerial view shows the brine pools and processing areas of the Soquimich lithium mine on the Atacama salt flat in the Atacama desert of northern Chile. Mining for the minerals that go into batteries, including lithium and cobalt, has big environmen­tal impacts.
PHOTO: REUTERS An aerial view shows the brine pools and processing areas of the Soquimich lithium mine on the Atacama salt flat in the Atacama desert of northern Chile. Mining for the minerals that go into batteries, including lithium and cobalt, has big environmen­tal impacts.
 ?? PHOTO: REUTERS ?? An Aries lithium iron phosphate battery pack is seen waiting to undergo testing at Our Next Energy headquarte­rs in Novi, Michigan, in the United States.
PHOTO: REUTERS An Aries lithium iron phosphate battery pack is seen waiting to undergo testing at Our Next Energy headquarte­rs in Novi, Michigan, in the United States.

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