CATL's Naxtra Sodium-Ion Battery Targets Cold Climates

Sodium goes mainstream

When CATL unveiled the Naxtra sodium-ion battery at its inaugural Super Tech Day on April 21, 2025, the company described it as the world's first mass-producible sodium-ion battery for passenger vehicles. That claim mattered less as a laboratory curiosity than as a manufacturing statement: CATL, the world's largest EV battery maker, was saying that sodium-ion chemistry — long dismissed as a low-energy also-ran — was ready for real assembly lines and real cars. Per CATL's own announcement, the Naxtra passenger EV cell achieves an energy density of 175 Wh/kg, the highest among sodium-ion batteries worldwide and roughly comparable to entry-level lithium iron phosphate (LFP) cells, with a 500-kilometer range and more than 10,000 charge cycles.

The chemistry has obvious appeal. Sodium is one of the most abundant elements on Earth, which frees battery makers from the price swings of lithium, cobalt and nickel. CATL argues that the material-level design removes the combustion-supporting factors found in lithium cells, giving the battery what the company calls intrinsic safety. Tested with crushing, drilling and sawing abuse, the cell stays smoke-free and fire-free, according to CATL, and even continues to deliver power after being cut in two.

Built for the deep freeze

The headline numbers, though, are about cold. Lithium-ion batteries lose usable capacity and power rapidly in freezing weather, which is one reason EV adoption has lagged in northern climates. Sodium-ion chemistry does not share that weakness. According to CATL, the Naxtra passenger EV battery operates across a range from -40°C to +70°C and retains 90 percent of its usable power at -40°C. Even with the state of charge down to just 10 percent, the company says the pack can sustain highway speeds of 120 km/h in -40°C conditions without significant power degradation.

Charging also holds up. Official test data published around the Naxtra launch showed that at -30°C the battery can charge from 30 to 80 percent in about 30 minutes while retaining 93 percent of its available capacity, per figures cited by ChinaEVHome. In CATL's February 2026 launch event with Changan, the company added that vehicles equipped with the Naxtra pack deliver nearly triple the discharge power of comparable LFP-equipped cars at -30°C, keep more than 90 percent of capacity at -40°C, and can still discharge stably at -50°C. For drivers in Heilongjiang, Minnesota or northern Scandinavia, those are the numbers that actually matter in February.

Changan puts Naxtra on the road

Production reality arrived on February 5, 2026, when Changan Automobile and CATL unveiled what the two companies called the world's first mass-production passenger vehicle equipped with sodium-ion batteries, at a launch event in Yakeshi, in Inner Mongolia's deep-cold test country. According to CATL, the car passed winter calibration in Yakeshi and is slated to reach the market by mid-2026. CATL's cell-to-pack system and battery management software give the vehicle a pure-electric range exceeding 400 km, the company says, with future sodium-ion variants projected to reach 500 to 600 km as the supply chain matures.

The partnership is not a one-car stunt. Changan says Naxtra batteries will spread across its full brand portfolio, including AVATR, Deepal, Qiyuan and UNI, while CATL outlined plans at its December 2025 supplier conference to deploy sodium-ion at scale in 2026 across four segments: battery swapping, passenger vehicles, commercial vehicles and energy storage. The heavy-truck side came first — the Naxtra 24V integrated start-stop battery for trucks entered mass production in June 2025, with an eight-year service life and, per CATL, a total cost of ownership 61 percent lower than the lead-acid batteries it replaces. CATL is also pairing the chemistry with its swap network, planning more than 3,000 Choco-Swap stations across 140 Chinese cities by the end of 2026, over 600 of them in colder northern regions.

A decade of quiet development

None of this happened quickly. CATL says it began sodium-ion research in 2016 and has since invested nearly 10 billion RMB (roughly 1.4 billion US dollars) and built nearly 300,000 test cells with a team of more than 300 R&D personnel. The hard part was not one breakthrough but a stack of them — cathode formulations that balance energy, safety and cycle life, and freeze-resistant electrolytes that keep sodium ions moving when everything else in a car is stiff with cold. Engineers worked through what the company describes as tens of thousands of material-level experiments to get there.

The commercial logic is getting clearer too. According to market estimates CATL cites from Precedence Research, the global sodium-ion battery market is expected to grow from about 1.39 billion US dollars in 2025 to 6.83 billion by 2034. Sodium-ion is not going to displace lithium in flagship long-range cars — its energy density still trails mainstream LFP, let alone high-nickel NMC. Instead it is carving out the segments where lithium is weakest: cold regions, short-range commuter cars, commercial fleets, stationary storage and starting batteries, where cost, safety and temperature tolerance dominate the purchase decision.

Regulation gives it a push

Chinese regulators have quietly raised the bar for all batteries, and sodium-ion clears it more easily than lithium. Naxtra has passed certification under GB 38031-2025, China's new national battery safety standard that takes effect July 1, 2026 and introduces stricter abuse testing, including localized scenarios that mimic real-world thermal events, per reporting by ChinaEVHome. CATL says the pack passed multi-surface crushing, nail penetration and drill penetration tests without fire or explosion — tests that many lithium packs still struggle to survive.

For the broader industry, Naxtra's message is that the battery world is becoming a two-chemistry ecosystem. CATL's own CTO for its China e-car business, Gao Huan, framed it that way at the Changan launch: lithium opened the era of electrification, and sodium extends it into places and price points lithium cannot comfortably serve. If the mid-2026 Changan launches sell in volume and the swap stations follow on schedule, 2026 will be remembered as the year sodium-ion stopped being a conference slide and became something you can actually buy — especially if you live somewhere the thermometer dips below minus thirty.