CATL Naxtra sodium-ion battery becomes the world’s first mass-produced option

The long-standing promise of electric cars that are as cheap as-or cheaper than-petrol and diesel models moved a step closer with the unveiling of the world’s first mass-produced sodium-ion battery.

It is called Naxtra, and it was one of three announcements made by CATL-the Chinese battery manufacturing heavyweight-at its recent Super Tech Day event. Alongside the sodium-ion pack, CATL also introduced two other batteries: Freevoy Dual-Power (effectively a battery within a battery) and Shenxing (designed to enable ultra-fast charging).

CATL Super Tech Day: Naxtra, Freevoy Dual-Power and Shenxing

CATL says its sodium-ion battery is intended to be a genuine alternative to lithium-ion batteries-particularly those using LFP (lithium iron phosphate) chemistry-because it has reduced or removed many of the drawbacks traditionally associated with sodium-ion technology.

Sodium batteries have existed since the 1990s and come with widely acknowledged benefits, including lower cost, improved safety and avoiding rare materials. However, their relatively low energy density (below LFP) and shorter charging-cycle life have kept them on the sidelines.

CATL Naxtra sodium-ion battery: energy density, cycle life and cost

With Naxtra, CATL claims to address those weak points by delivering an energy density of 175 Wh/kg and more than 10 thousand charging cycles. Those figures match-and, in the case of cycle life, exceed-what is typical for LFP batteries, making this chemistry far more plausible for future electric vehicle models.

LFP use has expanded sharply in recent years, driven in large part by the Chinese car industry, and the appeal is easy to understand: LFP packs are around 20% to 30% cheaper than lithium-ion batteries using NMC chemistry. Because sodium batteries rely on abundant, low-cost materials, they have the potential to be between 10% and 20% cheaper than LFP.

CATL even argues that its approach could cut our reliance on lithium while also “promoting the use of energy from ‘single-resource dependency’ to ‘energy freedom’”.

Cold- and fire-resistant

Cost is not the only claimed advantage. CATL also highlights Naxtra’s performance in very low temperatures: it retains 90% of usable energy at -40 ºC. Even at just 10% charge, the battery is said to keep working in extreme sub-zero conditions without major power loss.

Removing lithium also brings major safety benefits. Lithium-ion battery fires are known for being intense and difficult to extinguish, but CATL presents that as a non-issue for Naxtra. It says the material-level drivers of combustion have been eliminated, and describes the shift as moving from “passive defence” to “intrinsic safety”.

Goodbye to lead-acid batteries

As well as showcasing Naxtra for electric cars, CATL revealed a much smaller variant-Naxtra 24V Heavy-Duty Truck Integrated Start-Stop-aimed specifically at lorries, with the goal of replacing the traditional lead-acid battery.

According to CATL, the benefits are straightforward: an eight-year service life, a 61% reduction in lifetime costs compared with lead-acid, and, naturally, reliable first-try starts even in extreme cold (-40 ºC). CATL goes so far as to say that even if a vehicle has been left parked for a year, its sodium battery will still allow the engine to start on the first attempt.