Sodium vs. lithium-ion batteries: What's the difference between them?

Two battery technologies, one big question.

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Sodium-ion batteries aren't all that different from lithium-ion batteries in terms of how they operate. Both store and release energy by moving charged particles between negative and positive electrodes. The difference is mainly in the composition and which elements supply the ions.

A lithium battery moves lithium ions from the negative electrode to its positive counterpart, while a sodium battery moves sodium ions. The biggest difference between them is energy density, or how much energy the battery stores for its weight and size. Sodium-ion cells reach roughly 175 watt-hours per kilogram, roughly 20 to 30 percent lower than lithium-ion cells. Lithium-ion phosphate pushes the number to 205 watt-hours, and lithium NMC (nickel manganese cobalt oxide) takes it a bit higher to 255.

Since sodium ions are bigger and heavier than lithium ions, storage and space would be a disadvantage for the larger sodium-ion batteries. In addition, sodium-ion cells operate at lower voltages. That doesn't mean sodium-ion is useless, but it does have limitations. Some manufacturers like CATL and General Motors/Peak Energy are moving forward with larger-scale commercial production, so we may be seeing the initial stages of a bigger push towards sodium batteries just over the horizon.

How cost, cold weather, and safety compare

Sodium's biggest appeal is availability. The stuff is everywhere, especially compared to lithium. Unfortunately, the abundance of ingredients has yet to translate into mass production. Plus, lithium has a massive head start in production and use, and though it's easily the more expensive of the two, its costs are not quite low enough to justify a major industry takeover.

"Abundance" is also a loose term here. The availability of sodium is extensive, but it's not the sole material that goes into batteries like the sodium-ion battery in JAC Motors' 2024 EV. Sourcing for other components, like nickel and manganese, remains a challenge. Mass manufacturing doesn't begin overnight, and supply chains don't grow and organize in a day. There are positive signs in that direction, but sodium still has a way to go. 

When it comes to cCold weather performance, sodium-ion creeps ahead of lithium alternatives. According to the IEA, sodium-ion batteries retain 90% capacity at minus 40 degrees Fahrenheit. Lithium-ion takes a nosedive at similar temperatures. Sodium also has a lower risk of thermal runaway. The cells simply generate less heat and require fewer protection systems than their lithium-ion counterparts. That's not to say sodium-ion batteries are fireproof, but it's a good indicator that they may be a more stable option in a vehicle accident.

Is there a future for sodium-ion batteries

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As mentioned above, CATL and GMC are already on the move in this direction, along with HiNa Battery Technology, Natron Energy (now Draslovka) and others. Most are focused on automotive use cases, and a few on data center power. However, sodium-ion needs more applications to truly challenge Lithium's near stranglehold on the industry.

Stationary storage is a promising start. A battery installation supporting the electric grid doesn't have to tackle the same size and weight restrictions as EVs. If you're old enough to remember the Betamax versus VHS battle, it's a decent analogy. Betamax had some advantages over VHS and some disadvantages. But ultimately, VHS had the scale and consumer lock-in. The obstacles for sodium-ion are substantial. Global sodium production in 2025 was considerably lower than lithium-ion. For lithium, manufacturing is well established, with competitive LFP prices and robust supply chains.

In the end, the result may play out in a complementary fashion. Sodium-ion can fill in gaps lithium can't tackle, like extreme cold weather use or hybrid packs that let lithium do its thing while sodium tackles other use cases. Success might mean more choices, which usually works out well for the customer.