China's New EV Batteries Work at 40 Below Zero

Imagine an electric car battery that charges in Arctic temperatures and costs a fraction of today's price.

That's exactly what Chinese battery giants CATL and BYD are rolling out starting next year. Together, these two companies already control over half the global EV battery market, and now they're betting big on sodium-ion technology to solve two of electric vehicles' biggest problems: cold weather performance and rising costs.

CATL announced last week that its new "Naxtra" sodium-ion batteries will power passenger vehicles beginning in the second quarter of 2026. The first model, the AION Y Plus, is already undergoing winter testing in brutal conditions.

The results are impressive. At negative 40 degrees Fahrenheit, these batteries still retain 90% of their usable capacity. Traditional lithium batteries? Only about 80%. The sodium-ion batteries can even charge at negative 30 degrees, a temperature that would cripple most current EVs.

Chief technology officer Gao Huan explained that these batteries also handle ultra-fast charging better and more safely than lithium-ion. The 45 kWh battery packs are designed for small trucks, vans, and passenger vehicles, and they've successfully powered fully loaded vehicles up hills in freezing temperatures during testing.

BYD isn't sitting on the sidelines either. The company broke ground on its first sodium-ion battery plant in early 2024, investing $1.4 billion to reach an annual capacity of 30 gigawatt hours.

The timing couldn't be better. Lithium carbonate prices have skyrocketed to $24,500 per ton this year, up from around $7,200 per ton in 2021. Sodium, by contrast, is one of Earth's most abundant elements, found in regular salt. This means potentially lower costs and less strain on limited lithium resources.

The Bright Side

Right now, sodium-ion batteries have lower energy density than lithium alternatives, meaning they store less power for the same weight. But CATL aims to match lithium iron phosphate performance within three years.

The technology is already gaining momentum. Sodium-ion battery shipments hit 9 gigawatt hours last year, up 150% from 2024. Industry forecasts predict that number will explode past 1,000 gigawatt hours by 2030.

Other Chinese manufacturers including EVE Energy and Ronbay Technology are also jumping into sodium-ion production. Even individual EV owners are getting excited. One Tesla Model 3 owner recently swapped in a sodium-ion 12-volt battery, noting it weighs just 9 pounds compared to 29 pounds for lead-acid and is warrantied to last three times longer.

The shift to sodium-ion could make electric vehicles more practical in cold climates while driving down prices for everyone.