Sodium-ion batteries are happening — faster than you think
Lithium-ion batteries changed the world. Sodium-ion batteries want to make that change affordable.
Published on May 13, 2026
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© CATL
Mauro swapped Sardinia for Eindhoven and has been an IO+ editor for 3 years. As a GREEN+ expert, he covers the energy transition with data-driven stories.
Solar panels can be made as thin as a film, wind turbines can be made more compact without blades, but what about storing renewable energy at scale? Lithium-ion batteries dominated — and still do — the energy storage scene, but they come with significant downsides, scarce minerals, volatile prices, and supply chains controlled by a handful of countries.
Sodium-ion batteries (SIBs) are emerging as a promising alternative. They swap out lithium for sodium, an element we most know to be found in common table salt. SIBs promise safer, cheaper, and more geographically independent energy storage.
Why will they be the future of energy storage? They are certainly no longer a lab experiment, but the road to replacing lithium batteries is still long and bumpy. Let’s dive into them in the new episode of Green Tech Decoded.
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Green Tech Decoded
From revolutionary wind turbines to futuristic materials, a lot is happening in green tech. But what are all these technologies about? And why should we care? In Green Tech Decoded, we explain how these innovations work and why they could redefine our society.
What are sodium-ion batteries?
Sodium-ion batteries operate on the same electrochemical principle as lithium-ion batteries. During charging, sodium ions migrate from the cathode — the battery’s negative electrode – to the anode — the negatively charged electrode. In this transfer, ions pass through an electrolyte. When discharging, ions flow back, generating an electric current.
What are the pros of sodium-ion batteries?
The case for sodium-ion battery technology rests on several advantages.
Cheap, abundant raw materials. Sodium-ion batteries are made with sodium carbonate, a material that can be sourced more easily than lithium. Sodium is the sixth most abundant element in the Earth’s crust and costs $0.05 per kilogram. Chinese automakers use 5-10 kilograms of sodium in an average electric car battery pack.
No need for lithium, cobalt, or nickel. Not only lithium, but sodium-ion batteries, to be made, use no other rare critical minerals such as cobalt and nickel. Not only do these need important mining efforts to be extracted from the ground, but, as with lithium, their supply chains are exposed to geopolitical risks.
Long cycle life. Some sodium-ion battery designs can achieve over 15,000 charge cycles while retaining at least 80% of their capacity. In addition, they can do so even at extreme freezing conditions, with some sodium-ion cells retaining 90% of their nominal capacity at -40°C.
Safety. Sodium-ion batteries are inherently thermally more stable than many lithium-ion formulations — they don’t catch fire. SIBs have shown no thermal runaway during nail penetration, crushing, and overcharging tests — the industry-standard benchmarks.
Manufacturing compatibility. CATL, the world’s largest battery manufacturer, has designed its sodium-ion modules in the same form factor as lithium-ion. This means that energy storage integrators and car manufacturers can adopt the technology as a drop-in replacement, without the need to rehaul their production lines. Therefore, the switching barrier is lower.
What are the cons of sodium-ion batteries?
The technology's limitations are real, and understanding them matters for setting realistic expectations.
Lower energy density. This is the main pain point: how much energy can be stored in a kilogram of material. Sodium's atomic mass is roughly three times that of lithium, making it intrinsically less energy dense. Current best-in-class sodium-ion cells reach around 175 Wh/kg — CATL's second-generation Naxtra. By comparison, advanced lithium-ion cells can reach 250–300 Wh/kg. For long-range EVs where every kilogram of battery weight matters, this gap is significant.
Higher costs, for now. Despite cheaper raw materials, sodium-ion cells are currently more expensive per kilowatt-hour than mature LFP lithium-ion cells, at approximately $70/kWh, compared with $40–45/kWh for established LFP production in China. Why is it so? Because the supply chain for SIBs remains immature, production volumes remain low. As with every other technology, as manufacturing volumes grow, costs will decline.
Durability challenges in some chemistries. SIBs made using layered metal oxide cathodes can undergo a transition as more cycles are performed. This phenomenon, known as the P2-O2 transition, degrades the cathode over time. Scientists are researching ways to mitigate this problem, which, in other SIBs, is not present, at the cost of lower energy density.
The lithium price paradox. The economic case for sodium-ion is strongest when lithium is expensive. However, lithium carbonate prices — the formulation used to make lithium-ion batteries — have plummeted in recent years, narrowing sodium ion’s cost advantage. In an ever-swinging geopolitical and economic scenario, the economics of battery tech are never static.
Where does the technology stand now?
China is leading, and the gap with the rest of the world is wide. CATL launched its second-generation Naxtra series in 2025, co-unveiled the first mass-production sodium-ion passenger vehicle in February 2026, and signed a 60 GWh supply deal for grid storage shortly after. BYD is ramping a 30 GWh production facility in Xuzhou, targeting sodium-ion for 15–20% of its total battery demand by 2027.
Beyond China, other developments are unfolding. France's TIAMAT is building a 5 GWh factory in Amiens. In the US, Natron Energy supplies data center UPS systems using Prussian Blue cells, while Peak Energy has secured agreements to deliver 4.75 GWh of sodium-ion grid storage between 2027 and 2030.
What can we expect?
As the technology evolves, the International Energy Agency (IEA) believes 2026 to be a pivotal year for the success of sodium-ion batteries. However, the IEA also recognizes that lithium-ion batteries, particularly lithium-iron phosphate (LFP) batteries, offer significant advantages in energy density, supply chain maturity, and cost.
What could the role of sodium-ion batteries be then? They can excel in grid-scale storage, where cycle life is more relevant than weight, cheap EVs for cold climates, and all those applications where supply chain independence from lithium is non-negotiable. Lithium had a thirty-year head start. Sodium is closing the gap faster than anyone expected.