While car companies are pumping millions into researching new kinds of batteries, the game-changer that will put an EV in every driveway has been here for years, according to a pioneering battery expert.
Jeff Dahn, professor of physics and atmospheric science at Dalhousie University and Tesla Canada industrial research chair, says while solid-state batteries may one day have advantages, that is years away and will likely cost more for consumers. In the meantime, lithium-ion batteries will do the heavy lifting and prices are coming down.
“We can make wonderful cars today with the batteries we have now,” Dahn said. “But the number of cars is going to be massive and we’ll need batteries for energy storage as well – so there’s a role for every battery technology that you could think of.”
Since Tesla launched its Roadster in 2008, mass-produced EVs have used lithium-ion batteries.
While several companies are working on solid-state EV batteries, they might not make it into production vehicles for years. Plus lithium-ion batteries are proven, companies have years of experience making them, they’re slowly increasing in range and life span and they’ve been getting cheaper.
Here’s a quick EV Battery 101.
In 1996, GM used a lead-acid battery pack with a 125-kilometre range for its all-electric EV1. In 1999, it switched to nickel-metal hydride with nearly double the range.
But, unlike lead-acid and nickel-metal hydride, lithium-ion batteries use a liquid electrolyte to transfer energy – in the form of lithium ions – back and forth between the cathode (positive electrode) and the anode (negative electrode).
They have longer life and can deliver more power than their predecessors. They’re also better at handling hot and cold – and they’re recyclable.
Not all lithium-ion batteries are the same – they have different properties depending on the metals used.
“There are trade-offs that you make,” said Dahn, who helped develop the lithium-ion battery. “There are ways to do virtually everything you want, but not everything you want all at once.”
So, for instance, nickel-cobalt-aluminum oxide (NCA) lithium-ion batteries deliver a lot of range, but they require cobalt, most of which comes from the Democratic Republic of Congo and is connected to human rights abuses. It’s also expensive.
Last year, Tesla announced it was switching from NCA batteries to cheaper lithium-iron-phosphate (LFP) batteries, which don’t use cobalt, in its standard range vehicles. They deliver slightly less range and don’t handle the cold as well as NCA batteries.
Lithium-ion batteries use a liquid electrolyte that is heavy and flammable.
Several auto makers, including Mercedes, Toyota, Hyundai, Ford, GM, BMW and Volkswagen have invested in research into solid-state batteries. Instead of a liquid electrolyte, they use a solid electrolyte.
While tiny solid-state batteries are used now in smart watches and pacemakers, they’re not available yet in sizes big enough for EVs.
So why move to solid-state?
“The biggest advantage of solid-state batteries is that they don’t burn.” Dahn said. “But the safety record [of lithium-ion batteries] is incredible now compared to what it was like 10 years ago – and 10 years ago, it was really good. There have been all kinds of design innovations, and that’s only going to improve with time.”
Companies working on solid-state lithium batteries, including Colorado-based Solid Power, say they could some day deliver dramatic increases in range, lifespan and charging speed.
Dahn is skeptical.
“Maybe you could get a faster charge [from a solid-state battery], but you’ve got to think about faster charging for a minute,” he said. “If you’re doing most of your charging at home, really, what’s the need for a faster charge?”
Plus, the lithium-ion batteries we use now will likely outlast your car.
While some consumers considering an EV say they want about 600 kilometres of range, Dahn thinks today’s batteries provide enough range – 300 to 500 kilometres in most new models – for most of us.
“I think this whole point about range is overblown,” Dahn said. “I think once people own an EV, they realize that they’re parking it at home and they can have the thing fully charged, or almost fully charged, every single morning before they go anywhere.”
Dahn expects solid-state batteries, if they arrive in production vehicles, to cost more than lithium-ion batteries.
Not only will the electrolyte likely be more expensive, but years of design and production advances have driven down the cost of lithium-ion EV batteries every year.
Although battery prices fell 89 per cent between 2010 and 2020, they still count for about 30 per cent of the cost of an EV, according to BloombergNEF.
But the main focus on lithium-ion battery research now – and the best way to get people into EVs – is to drive battery cost down even further, Dahn said.
“That’s made difficult because the price is increasing for some of the components – the price of lithium increased by 400 per cent in 2021,” Dahn said. “We’re doing everything we can, but supply and demand is driving price up. To make lithium-ion batteries you need lithium.”
BloombergNEF expects battery prices to rise slightly this year for the first time since 2010.
Surge in demand
Lithium prices are surging because of increased demand for EVs worldwide.
That demand will only keep rising, Dahn said.
But, getting carbon emissions down will require more than just more EVs. Solar and wind power also need batteries to store energy for later use.
“In 2030, it’s projected that 90 per cent of all lithium-ion batteries will go into vehicles,” Dahn said. “So we’ll need all the other kinds of batteries that we can get for energy storage.”
That includes lithium-free battery tech, including iron-air and sodium-ion, which can’t store as much energy as lithium-ion batteries.
EVs themselves could also play a role in energy storage if car makers and utilities allow bidirectional charging – where the power company could take power from your car when you’re not using it.
“We’ve got to go faster [to slow climate change] than we’re going at the moment,” Dahn said. “But the nice thing about all this is that EVs work really well and energy storage works really well. So, we have solutions – if we can bring them online, we’re in good shape.”