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

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

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

Although these electric vehicles are unlikely to reach the United States, the announcement from CATL – which, as the world’s largest manufacturer of electric vehicle batteries, produces about 40% of the world’s supply – offers an early signal as to whether sodium-ion technology can potentially reduce battery costs or improve the performance of electric vehicles in winter.

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

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

Beat the cold

Currently, the majority of electric vehicles around the world are powered by lithium-ion batteries, which are more powerful than sodium-ion batteries but perform differently in cold weather than in hot weather. At low temperatures, many lithium-ion electric vehicles provide less power and charge more slowly.

Batteries store and release energy by circulating charged particles between electrodes via an electrolyte; cold temperatures slow these processes.

As their name suggests, sodium-ion batteries replace lithium with sodium, an abundant element widely found in salts.

Although sodium ions are larger, they form weaker bonds with the liquid electrolyte than lithium. This allows them to break off and move around much more easily than lithium ions, even when cold makes the electrolyte thick, Liu says. “Cold weather slows the movement of all ions, but sodium-based systems are often less affected, allowing them to retain more power and capacity in 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-range batteries that dominate China’s electric vehicle market. The battery can charge to 90% when the temperature drops to –40 degrees C (–40 degrees F) and reaches “steady power” at –50 degrees C under testing conditions, the company notes.

Charging and discharging at –50 degrees Celsius is “scientifically possible, although extremely difficult,” says Kenil Rajpura, a materials scientist at Pandit Deendayal Energy University in India. He says achieving these temperatures depends on careful use of materials and pack design, including electrolytes that continue to function in extreme cold.

By comparison, many lithium-ion batteries struggle at these extremes. “At these temperatures, most lithium-ion batteries would only deliver a very small fraction of their original capacity unless the pack is equipped with an active heating system,” says Liu.

Charging in cold weather can also be risky for lithium-ion batteries because the ions cannot penetrate the anode quickly enough, causing them to deposit on the surface. This can damage the battery and, in the worst case, lead to safety risks, says Rajpura.

Still, the numbers shared by CATL are likely the best results from controlled testing, according to Xing Lei, an independent U.S.-based analyst of the Chinese auto industry. They serve as reference points with which to “take a grain of salt,” Xing says. The real-world performance of these electric vehicles will depend on a number of factors, including how customers use them.

Store more energy

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

CATL installed its first sodium-ion batteries in a car manufactured by Chery in 2023. These vehicles had a range of only 170 kilometers and yet sold poorly, according to an analysis by the Shenzhen-based research institute Starting Point.

But the newly announced model is expected to have a range of 400 kilometers under the China Light Vehicle Test Cycle (CLTC), a laboratory test, thanks to Naxtra’s improved energy density. CLTC lab test results are often higher than the U.S. Environmental Protection Agency’s range ratings, and drivers may see lower range in the real world. The figure provided by CATL is as high as 175 watt hours per kilogram, which is approximately 90% of the energy density of current LFP batteries.

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

CATL’s cell-to-pack system also increases energy density by placing battery cells directly into a pack instead of grouping them into separate modules first, which reduces additional material and weight, says Chen Shan, an analyst at energy research firm Rystad Energy.

Although sodium is plentiful, the young supply chain means that making these batteries currently costs about 30% more 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 much, sodium-ion technology could find a foothold in colder regions, says Phate Zhang, founder of Shanghai-based electric vehicle news media CnEVPost. “Otherwise, it might remain a niche chemistry for now,” he says.