They’re cheaper than their lithium counterparts. Can they become as powerful?
With EV production and the green energy revolution hitting their strides, lithium-ion batteries have been supplying the power for a lot of new products. Lithium is abundant, light, and energy-dense. It has a lot going for it, and demand for lithium-ion batteries is skyrocketing. There might be a challenger emerging to knock lithium off its pedestal. Sodium is not quite as abundant, but it’s a lot easier to extract. In a decade or so down the road, we could see sodium-ion batteries give lithium-ions a run for their money.
Lithium vs. Sodium
There’s a lot of lithium in the ground, no doubt, but getting it out and ready for use in batteries isn’t so easy. There’s also the challenge of where lithium is found. Chile has the most reserves at 8 or 9 million tons, with Australia a distant second. Argentina and China are next in the rankings. When it comes to productivity, however, Australia is far and away the world leader, producing about three times what Chile does annually. The U.S. is behind those countries in lithium reserves and has only one active lithium mine.
The high demand combined with the extraction difficulties has made lithium expensive. At one point in 2022, lithium carbonate cost more than $80,000 per ton, though that has dropped significantly. When it comes to sodium carbonate, or soda ash, costs are around $3,000 per ton and about 90% of the world’s readily mined reserves are in the U.S.
Sodium is not as energy dense as lithium, so sodium-ion batteries take up more space and are heavier than lithium-ion ones. That presents a challenge for EV makers who are striving for lighter cars with longer ranges. Sodium-ion batteries do perform better in low temperatures, though, and they don’t need nearly as much cobalt and nickel to run. And while size might be a problem for sodium-ion batteries in cars, it’s not such a big deal for electrical grids. Refining natural soda ash for battery use is also a more sustainable process than refining lithium carbonate.
China & Sodium-Ion EVs
Given that lay of the land, it’s a bit surprising to learn that 16 out of the world’s 20 existing or planned sodium-ion battery factories are in China, which produces synthetic soda ash made with coal power. That means most of the sodium-ion batteries being produced use the dirtiest energy source.
China-based battery manufacturers CATL and BYD both have plans for EV batteries that are a combination of lithium and sodium ions. CATL is putting lithium-sodium-ion batteries in the Chery iCAR set to go to market this year, and BYD will put them in its Seagull.
In March, China-based JAC Motors announced the world’s first sodium-ion powered EV, Hua Xianzi (flower fairy). The sodium-ion batteries come from HiNa Battery and have a range of about 250 kilometers (155 miles) on a single charge.
“The future of electric vehicles looks promising with the introduction of more affordable and sustainable battery technology,” said Karl-Heinz Göbel, EO of JAC Motors South Africa. “With the development of new battery technology, EV pricing will become more competitive, giving more car buyers access to new-energy vehicles.”
That’s a far cry from the longest-range EVs on the road right now, but the costs for these sodium-ion EVs are a lot less than their lithium-ion counterparts. Current sodium-ion battery technology is about where lithium-ion EV tech was a decade ago. With more R&D, it’s entirely possible the ranges even out while prices remain far apart. In that scenario, sodium-ion batteries win out.
Still, there are a lot of unknowns for the potential of sodium-ion batteries. The Chinese manufacturers have left a lot of questions about their performance unanswered.
“They’re making these quite interesting announcements. There’s also a lot of details missing,” Andy Leach, an energy storage analyst at BNEF, told the MIT Technology Review.
Researchers at Cornell University might have found a key to increasing the lifespans of sodium-ion batteries, observing crystal defects while the batteries are running that disappear when they’re at rest.
“If we looked at the battery before and after the first charge-discharge cycle, we would see no defects. But during the operation, we see how the defects form and self-heal, leaving detectable ‘scars’ behind,” project lead Andrej Singer told the Cornell Chronicle. “We have yet to understand the role of extended defects in battery materials. For centuries, blacksmiths used defect engineering in metals to create stronger and more durable materials without even realizing it. Applying a defect-engineering approach to ceramics is much more challenging due to the presence of electrostatic charges. Nevertheless, with the help of new operando measurements and a better understanding of the mechanisms involved, we can now begin to address this challenge.”
In the U.S., companies like Natron are using sodium-ion batteries for larger, grid-scale purposes such as powering data centers as well as for EV fast chargers. Pacific Northwest National Laboratory researchers are using low-solvation electrolytes to extend sodium-ion battery life.
“Here, we have shown in principle that sodium-ion batteries have the potential to be a long-lasting and environmentally friendly battery technology,” lab fellow Jason Zhang said.
If that potential is reached, they could outlast lithium-ion batteries,