Are Lithium-ion (Li-ion) batteries the only game in town for the new wave of electric vehicles and other applications?
Until quite recently, the answer was yes.
BUT they now have competition from Sodium-ion (Na-ion) batteries which, though not yet commercially available, are showing great promise.
Yes, technologists discover new improvements of Li-ion batteries almost daily and Giga-factories are being built to produce them, but Li-ion batteries have problems that the Na-ion batteries can solve: security of supply, price and safety.
About 90% of the world’s supply of lithium is controlled by Chinese companies and US and EU car manufacturers are very concerned about that. Therefore, Na-ion batteries, long supposed to be only second best, gain attention.
In 2019, lithium hydroxide cost $6,000 per metric tonne. Now it is $78,032.
Sodium hydroxide’s price is stable below $800 per ton. It is in ample supply, produced with chlorine by electrolysis of salt. But will the price difference be enough to ensure the future of the Na-ion battery?
Li-ion batteries have been known to catch fire and pose a safety threat we are all aware of, but Na-ion batteries do not catch fire
Li-ion batteries perform better because their energy density is higher. A key characteristic for many applications of these batteries, in particular automotive.
But industry is rethinking this matter as price becomes an issue. On a second look, automotive isn’t the only application. There are stationary applications as well. And Na-ion batteries have a few advantages. They perform quite well at low temperatures, in the range of -20 degrees C.
Present-day Na-ion batteries have an energy density of about 160 W h/kg, similar to that of older Li-ion batteries. (Modern Li-ion batteries attain 230 W h/kg or a bit more). At this power density, batteries generally don’t need cooling, which may be an advantage.
Faradion, one of the developers of Na-ion batteries, expect their batteries to reach an energy density level of 190 W h/kg in the next few years. This year, Faradion was bought by the Indian company Reliance Industries. They plan to build a Na-ion factory in India, for applications such as slower electric vehicles, and stationary power storage.
California-based start-up Natron Energy batteries are unique in being able to deliver huge amounts of power over short durations. They are suitable as auxiliary power for industrial applications, for instance data centres.
Altris, a Swedish company intends to construct a commercial Na-ion battery plant soon.
Na-ion batteries are moving from pilot- to commercial-scale production. The supply chain issues with lithium opened up the window of opportunity for them.
Would you back Na-ion batteries development over Li-ion technology in the medium term?
Written by William Colquhoun This article was first published here.