Argonne-led effort aims to produce a lower-cost EV battery running on sodium
Argonne National Laboratory in Lemont is leading a partnership of seven U.S. national laboratories in a new, $50 million initiative to accelerate the development of sodium-ion batteries for electric vehicles and energy storage.
A shift to the use of these batteries could lead to lower costs, less risk of fire and less of a need for lithium, cobalt and nickel.
Currently, no passenger cars or trucks sold in the United States use sodium-ion batteries. Some sodium-ion models are available in China and in countries that import vehicles from China.
Shortly before the new partnership was unveiled last month, the Chinese company CATL, which is the world’s largest battery manufacturer, announced it plans to begin mass production in 2027 of its second-generation sodium-ion battery. It says the new battery will have an energy density of 200 watt-hours per kilogram. That would be an increase from 160 watt-hours per kilogram for the previous generation that launched in 2021. Higher energy density in an EV battery means the vehicle will have a longer driving range.
The two announcements are part of a broad shift, as governments, researchers and companies seek alternatives to lithium-ion batteries — now the dominant technology for EVs and energy storage.
“The reason we're pursuing this is very simple,” says Venkat Srinivasan, a battery scientist at Argonne who’s the director of the new collaboration. “It's because the huge demand in lithium-ion batteries has meant that we have a supply-chain constraint.
“We have a problem with cobalt, we have a problem with nickel,” Srinivasan says of two of the metals often used in lithium-ion batteries.
Cobalt, nickel and lithium all also pose other concerns, including the environmental damage associated with mining the elements.
Beyond that, much of the supply is controlled by U.S. geopolitical rivals including China. And some of the mining takes place in countries with inadequate labor standards.
In contrast, sodium-ion batteries rely on sodium, a common element found in table salt and ocean water.
CATL says its new battery works in temperatures as low as 40 degrees below zero Fahrenheit.
Sodium-ion batteries also pose a much lower risk of fire. When lithium-ion batteries sustain damage, it can lead to “thermal runaway,” triggering a toxic fire.
Manufacturing sodium-ion batteries is similar enough to making lithium-ion batteries that companies can shift assembly lines from lithium to sodium without costly retooling.
Among the other benefits, sodium-ion batteries perform better than lithium-ion batteries in extreme cold.
But sodium-ion batteries have some disadvantages. The big one: They have a lower energy density than lithium-ion. So an EV running on a sodium-ion battery will go fewer miles per charge than one with a lithium-ion battery of the same size.
“That is just what nature has given us,” Srinivasan says. “From a physics perspective, sodium batteries inherently have lower energy density than lithium batteries.”
A typical sodium-ion battery has an energy density of about 150 watt-hours per kilogram, he says. Lithium-ion batteries can range from about 180 watt-hours per kilogram to nearly 300.
Asked about CATL’s assertion that its sodium-ion battery will have a much-improved energy density of 200 watt-hours per kilogram, Srinivasan says, “We tend to be skeptical of news releases from companies.”
The national labs’ initiative has a five-year timeline, with a goal of developing sodium-ion batteries with energy densities that match or exceed those of today’s iron phosphate-based lithium-ion batteries. They’re aiming to do this by finding efficiencies in design and materials.
The labs also continue to work on developing and improving other kinds of batteries as well.
Lithium-ion remain the dominant batteries. But sodium-ion battery production is growing, projected to reach 140 gigawatt-hours by 2030, which would be about 13 times its current level, according to Benchmark Mineral Intelligence. Lithium-ion production also is projected to nearly triple by 2030.
“The key market driver for sodium-ion batteries is their potential to be cost-competitive with lithium-ion batteries,” says Catherine Peake, an analyst for Benchmark.
For now, that’s difficult because lithium prices are unusually low, as the global supply has grown more rapidly than demand since 2022, leading to lower prices.
In the long run, though, researchers and analysts expect sodium-ion batteries will have a cost advantage over lithium-ion. McKinsey and Co., the consulting firm, said last year that sodium-ion batteries have the potential to cost 20% less than lithium-ion batteries. Srinivasan agrees such savings is plausible.
By the end of the decade, another alternative, solid-state batteries, will begin to become available, allowing for higher energy densities and longer driving ranges.
The technologies can coexist, according to Srinivasan. He says solid-state batteries will initially be most common in high-end models and popular with people who want the longest possible ranges. He expects that sodium-ion batteries will be more common in low-cost EVs for people who live in cities or suburbs and don’t place a high premium on driving range.