Safety
Sodium-ion batteries in cold weather
Cold performance is sodium-ion’s most convincing technical advantage, but the charge limit on the actual product matters more than a chemistry-wide claim.
Why batteries slow down
Low temperature increases resistance and slows ion transport. Available power falls, voltage sags and charging becomes harder. A battery-management system may reduce current or block charging to protect the cell.
The sodium advantage
The IEA reports that the latest sodium-ion generation can retain around 90% of nominal capacity at -40°C. CATL reports stable Naxtra operation from -40°C to 70°C. UK home products use their own, narrower pack limits: Eleven Energy lists Galvani charging from -20°C and discharging from -30°C.
UK reality
Most of Britain rarely sees those extremes, but batteries in detached garages, sheds and exposed cabinets can spend long periods below the comfortable range of a lithium pack. Check whether a quoted minimum applies to storage, discharge or charge; they are three different limits.
Questions answered
Does sodium-ion need a heater?
Some products can charge below 0°C without one, but follow the product’s charge-temperature specification.
Will it have full power at -20°C?
Not necessarily. An operating limit is not a promise of room-temperature capacity or output. Look for a power and capacity curve.
Sources
- Sodium-ion battery momentum grows, but challenges remain — International Energy Agency, 17 February 2026.
- CATL and CHANGAN launch sodium-ion passenger vehicle — CATL, 5 February 2026.
- Galvani stackable sodium-ion battery — Eleven Energy, checked 10 November 2026.
Sources last checked 10 November 2026. Product availability can change.