Is Sodium the new Lithium (ion)?

The case for sodium is mostly not about the battery itself. It is a family of chemistries rather than one, and close enough to lithium-ion to be built on much the same equipment, so it inherits twenty years of manufacturing progress instead of starting over, as is already happening, mostly in China. Sodium is heavier, though he says not so heavy that lower-range transport is out of the question, and points to at least two Chinese electric vehicle brands already rolling out sodium-ion products. It is far more abundant, which he thinks matters less for price than people assume, since high lithium prices keep producing more lithium, and more for supply chains, since China refines most of the world’s lithium, though he grants China also leads sodium-ion manufacturing. Sodium cells also carry an inherently lower risk of thermal runaway and can use non-flammable electrolytes, which he says can trim fire-suppression cost at the pack level, though he grants the lithium-ion industry has made great progress on fire risk over the past decade.

Against that, LFP is a juggernaut and still getting cheaper, so a chemistry cheaper in theory may never win the volume to prove it. The Nature paper the post is built around combines learning curves with bottom-up costing, and its headline is that sodium could begin to outcompete lithium by the mid-2030s where energy density is not a major constraint. He tells the reader not to lean on that date, which rests on assumptions about deployment and mineral markets, and to look instead at the floors under both curves. LFP cannot fall below the cost of its lithium, iron and phosphate, and lithium’s scarcity makes that floor likelier to rise. Sodium’s floor, in nickel-free formulations, is a couple of dollars and is going nowhere, so a sodium cell is almost entirely manufacturing cost, and manufacturing is what scale makes cheaper. That asymmetry, rather than the crossover year, is the argument.