Sodium-ion battery
Also known as: Na-ion battery, sodium battery
A sodium-ion battery works much like a lithium-ion battery but moves sodium ions, the same element found in table salt, instead of lithium.
Sodium is cheap and abundant, and the batteries often perform better in cold weather and avoid lithium, cobalt, and nickel. While sodium-ion cells store less energy for their weight, that trade-off suits grid storage and affordable city cars, where cost matters more than maximum range.
Sodium-ion battery, explained at three levels
At home
A battery is like a shuttle bus carrying passengers between two stations. When you charge it, charged particles called ions ride over to one side and wait. When you use the battery, they ride back, pushing electricity through your device. Most batteries use lithium as the passengers. A sodium-ion battery uses sodium, the element in table salt, which is cheap and found almost everywhere.
At work
A sodium-ion battery stores energy by moving sodium ions between two electrodes, the same principle as lithium-ion. Sodium is abundant and cheap, and these cells avoid lithium, cobalt, and nickel, whose supply chains are concentrated in a few countries. That makes them attractive for stationary storage and low-cost vehicles, where price matters more than maximum energy per kilogram.
At home
Sodium ions are bigger than lithium ions, so they cannot slip easily into the graphite used in lithium batteries. Instead, sodium cells use hard carbon, a disordered carbon with larger gaps. The cell stores less energy for its weight, so an EV would get less range. In exchange, sodium cells tend to keep more capacity in freezing weather, can usually be discharged to zero volts for safe shipping, and are considered less prone to fires.
At work
Cathode chemistries fall into three families: layered oxides, which offer higher energy density; Prussian blue analogues, which are cheap and fast-charging; and polyanionic compounds, which are stable and long-lasting. Most are paired with hard carbon anodes. Because the cells use formats similar to lithium-ion, they can be built on adapted lithium-ion lines, and they can use aluminum instead of copper foil on the anode side, cutting material costs. Early markets include grid storage, two-wheelers, and entry-level EVs.
At home
Sodium atoms are about three times heavier than lithium atoms and their ions are larger, which caps how much energy a cell can hold. CATL's newest Naxtra cells reach about 175 watt-hours per kilogram, close to lithium iron phosphate (LFP). While that gap is narrowing, in my opinion the real question isn't whether sodium-ion beats lithium in general, but whether it beats LFP on cost, since that's the chemistry it competes with directly.
At work
The business case swings with lithium prices. When lithium spiked in 2022, sodium-ion looked compelling; when prices collapsed, the advantage narrowed, and some Western makers, such as Natron Energy, shut down. Evaluate cycle life, cold-weather performance, safety certification such as UL 9540A for storage, and the maturity of the hard carbon supply chain. Hybrid packs that mix sodium and lithium cells under one battery management system are one way to balance range and cost.
Real-world examples
At home
Lena lives in Winnipeg, where winters regularly reach -30°C. She read that sodium-ion batteries keep more of their capacity in extreme cold, which made her curious about future EVs and home storage using them.
At work
Marcus is a procurement manager for a Canadian solar-plus-storage developer. His team is evaluating sodium-ion batteries for a remote community project, attracted by cold-weather performance and lower fire risk, while waiting for longer field data.
How it compares
| feature | Sodium-ion battery | Lithium-ion battery |
|---|---|---|
| Key element | Sodium, abundant | Lithium, more limited supply |
| Energy density | Lower | Higher |
| Cold-weather performance | Generally better | Weaker in deep cold |
| Maturity | Early mass production | Mature, widespread |
Sodium-ion gives up some energy density for lower cost and abundant materials.
For analysts
Sodium-ion is a good example of 'good enough' technology winning on cost. I'd consider it for stationary storage where weight doesn't matter, once suppliers can show warranty terms and field data comparable to LFP.
History & origin
Researchers studied sodium batteries alongside lithium in the 1970s and 1980s, but lithium won because it stored more energy. Interest returned in the 2010s as lithium prices swung and supply chain concerns grew. Britain's Faradion and France's Tiamat developed early commercial cells. China's CATL unveiled its first-generation sodium-ion battery in 2021, and small Chinese EVs with sodium-ion packs appeared in 2023. CATL announced its Naxtra sodium-ion brand in 2025 and said in 2026 that mass production was under way, with passenger car and commercial vehicle launches. US startup Natron Energy, which made sodium-ion cells for data centres, shut down in 2025. In my view, sodium-ion won't replace lithium, but it will put a ceiling on how expensive lithium can get.