Sodium-ion battery technology: So near and yet so far

Over the past two to three years, the buzz around sodium-ion batteries has become louder, with some companies claiming a succession of new breakthroughs. While these developments are promising, there are still significant hurdles to broader sodium-ion adoption.  

Sodium has a big advantage over lithium when it comes to availability, but it cannot yet match lithium’s performance parameters. Additionally, lithium carbonate prices have crashed by more than 70% over the past several years, negatively impacting the business case for sodium-ion batteries.  

US-based sodium-ion battery tech startup Bedrock Materials recently announced that it is winding down its operations, due in part to these cost competition challenges. The Stanford University spin-out was advancing research on sodium-ion battery tech for EVs, anticipating a continued lithium shortage that would make sodium-ion batteries a viable alternative.

Spencer Gore, co-founder and CEO at Bedrock Materials, said in a statement: “Our modeling pointed to a clear outcome: in a world where lithium remains abundant, today’s sodium-ion batteries can’t compete on cost — even at commercial scale. Independent researchers at Stanford reached the same conclusion, noting that for sodium-ion to succeed, it would need either a breakthrough in energy density or to carve out niche applications based on unique performance traits”.

Due to the decline in lithium prices, sodium-ion batteries have experienced a significant reduction in their primary value proposition compared to lithium-based batteries. Currently, the prices of sodium-ion batteries in China can be as much as twice that of LFP batteries, particularly for the mixed metal oxide cathode materials that provide the acceptable energy density levels needed in the automotive sector. 

Consequently, sodium-ion cell suppliers are exploring niche applications to increase production volumes, which is essential for achieving economies of scale and driving price reductions.

According to S&P Global Mobility battery expert Ali Adim, there is an opportunity for sodium-ion batteries to see wider adoption in the low-voltage battery segment, thanks to their excellent performance in freezing temperatures.  

“Starter batteries present a compelling opportunity for sodium-ion adoption, thanks to their cold cranking capability. Interestingly, CATL promotes a lower total cost of ownership for its low-voltage sodium-ion batteries compared to traditional lead-acid batteries, due to a longer lifespan. In the coming years, we anticipate that the use of low-voltage sodium-ion batteries for starter and auxiliary functions will expand into the light-duty vehicle sector, particularly as legislation in regions like Europe moves to ban or restrict lead,” he said.