CATL sodium-ion battery aims to improve EV winter range loss

A common element found in table salt could be the key to powering China’s next wave of electric vehicle (EV) adoption.

Cars with a sodium ion battery, an emerging technology, are slated to go on sale in the country by mid-2026, according to battery maker Ningde, China-based Contemporary Amperex Technology (CATL) and vehicle maker, Chongqing, China-based firm Changan Automobile.

While these EVs are unlikely to come to the U.S., the announcement by CATL — which, as the world’s largest producer of EV batteries, accounts for an estimated 40 percent of global supply — provides an early signal about whether sodium-ion technology could eventually lower battery costs or improve EV performance in the winter.

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The battery, called Naxtra, can perform stably at -50 degrees Celsius (-58 degrees Fahrenheit), CATL says – a feature that could solve one of electric cars’ biggest drawbacks: the reduced range and slower charging caused by deep cold. For anyone who has seen their car’s range drop on a cold morning, this claim is hard to ignore.

“It may also benefit other cold areas, such as parts of the United States, Canada and Europe,” said Liu Chenguang, a battery researcher at Xi’an Jiaotong-Liverpool University in China. Minnesotans and upstate New Yorkers, rejoice.

Conquer the cold

The majority of electric cars in the world right now are powered by lithium-ion batteries, which are more powerful than sodium-ion batteries, but perform differently in cold weather than they do in hot conditions. In low temperatures, many lithium-ion electric cars deliver less power and charge more slowly.

Batteries store and release energy by moving charged particles between electrodes through an electrolyte; cold temperatures make these processes slow.

As the name suggests, sodium ion batteries replace lithium with sodium, an abundant element found in salt.

Although sodium ions are larger, they form weaker bonds with the liquid electrolyte than lithium does. This allows them to dislodge and move much more easily than lithium ions, even when the cold makes the electrolyte thick, says Liu. “Cold weather makes all ions move more slowly, but sodium-based systems are often less affected, so they can retain more power and capacity in the winter.”

CATL claims that at -30 degrees C (-22 degrees F), Naxtra can deliver nearly three times the discharge power of equivalent LFPs, or lithium iron phosphate (LFP) batteries, the cheap standard batteries that dominate the Chinese EV market. The battery can be charged to 90 percent full when the temperature drops to -40 degrees C (-40 degrees F) and achieves “stable power delivery” at -50 degrees C under test conditions, the company notes.

Charging and discharging at -50 degrees C is “scientifically possible but extremely challenging,” says Kenil Rajpura, a materials scientist at Pandit Deendayal Energy University in India. He says reaching these temperatures depends on careful use of materials and package design – including electrolytes that continue to work in extreme cold.

In comparison, many lithium-ion batteries struggle in these extremes. “At these temperatures, most lithium-ion batteries will only deliver a very small fraction of their original capacity unless the pack has an active heating system,” Liu explains.

Charging in the cold can also be risky for lithium-ion batteries because the ions cannot enter the anode quickly enough, causing them to be deposited on the surface. It can damage the battery and, in the worst case, cause safety hazards, says Rajpura.

Still, the figures CATL has shared are likely best-case results from controlled tests, according to Xing Lei, a US-based independent analyst of the Chinese auto industry. They serve as reference points that one should “take with a grain of salt,” says Xing. How these EVs perform in the real world will depend on a number of factors, including how customers use them.

Save more energy

Over the past decade, CATL has spent nearly 10 billion yuan ($1.4 billion) and put more than 300 employees into developing sodium-ion batteries, according to the company.

CATL put its first sodium-ion batteries in a Chery-made car in 2023. Those vehicles had a range of just 170 kilometers and sold poorly, according to an analysis by Shenzhen-based Starting Point Research Institute.

But the newly announced model is expected to have a range of 400 kilometers on the China Light-Duty Vehicle Test Cycle (CLTC), a laboratory test, thanks to Naxtra’s improved energy density. CLTC lab tests are often higher than US Environmental Protection Agency ratings, and drivers may see less range in the real world. The figure provided by CATL is up to 175 watt-hours per kilogram, which represents about 90 percent of the energy density of current LFP batteries.

Rajpura calls the number “the upper commercial limit” for current sodium ion technology. Liu calls it “a strong number” that suggests sodium-ion batteries are becoming practical for shorter-range, city-focused cars.

CATL’s cell-to-pack system also increases energy density by putting battery cells directly into a pack instead of wrapping them in separate modules first, which cuts extra material and weight, says Chen Shan, analyst at energy research company Rystad Energy.

Although sodium is abundant, the young supply chain means that producing these batteries is currently about 30 percent more expensive than making comparable lithium-ion batteries in China, realistically pushing mass production toward the end of this decade, Xing says.

If the car performs well at low temperatures without costing a premium, sodium ion technology could find a foothold in colder regions, says Phate Zhang, founder of Shanghai-based EV news outlet CnEVPost. “If not, it may remain a niche chemistry for now,” he says.