In every corner of the internet you can find a few morsels of information about the plans of sodium-ion cell manufacturers. But what happens when you put all this data together? What new insights can be gained from the data? The results of the research are presented here.
There are now lots of sodium-ion companies. A list of which manufacturers there are, where they come from and what energy densities are planned can be found in this article.
But what can you learn from the data if you compile all the information? The 5 most important takeaways are discussed in this article.
Takeaway 1: Cathodes based on layered oxides dominate the market
Even if not all manufacturers have yet revealed which cell chemistry they are working on, it is clear that cathodes based on layered oxides account for by far the largest share. Layered oxides are already known as a cathode material for lithium-ion batteries and are relatively easy to integrate into existing processes: it is a drop-in technology. This makes it possible to save the costs of new systems and also to reach market maturity quickly.
Prussian blue analogs have a much smaller market share of just under 15 %. However, this technology is favored by large companies such as CATL and Northvolt, so a successful market launch is definitely realistic.
Polyanionic cathodes, on the other hand, are currently only being pursued by a few manufacturers. BYD is focusing on this technology, but also wants to develop layered oxide cathodes as a second mainstay. Compared to the other two chemistries, series production is still a long way off.
Layered oxides, Prussian blue and polyanionic cathodes account for more than 2/3 of the total market. However, there are also some manufacturers who are going their own way and working on solid-state sodium-ion batteries, for example, often in combination with a sodium metal anode. Some of their systems have been available on the market for several years. What they all have in common, however, is that they either have glaring disadvantages compared to conventional materials (e.g. operating temperature at 300° C) or are still a long way from being ready for the market.
While there is a competition for the best chemistry for cathodes, this battle has long been decided for the anode. Almost all suppliers rely on hard carbon, occasionally also soft carbon. The graphite used as an anode material for lithium-ion batteries cannot be used for sodium-ion batteries (the sodium ion is too fat, so it cannot be properly intercalated in the intermediate layers of the graphite). Hard carbon has a coarser structure with imperfections and niches that can absorb the sodium ions, which is why it is the preferred material for manufacturers.
Further information on the battery chemistry of sodium-ion batteries can be found in this beginner’s article.
Takeaway 2: It doesn't matter whether layered oxide or Prussian blue analogs: the planned energy density is barely any different
It is known from research that layered oxide cathodes achieve the highest energy density, followed by Prussian blue analogs, with polyanionic cathodes bringing up the rear. Even if this fundamental trend is also reflected in the manufacturers’ announcements, the differences between layered oxides and Prussian blue analogs are only minimal in practice and therefore negligible. In fact, the two materials are in a neck-and-neck race and it is not yet clear which will ultimately prevail.
Takeaway 3: Sodium-ion batteries are good, lithium-ion batteries are better
Even though sodium-ion cells have made significant progress in recent years and are already performing better than many lithium-ion cells manufactured in 2010-2020: Today’s lithium-ion batteries are better. With lithium NMC and NCA cathodes, energy densities beyond 200 Wh/kg are achieved and with LFP there is a technology that already survives 6000 cycles. With polyanionic cathodes, there is also a technology for sodium ions that enables up to 10,000 cycles, but this is at the expense of energy density.
Many manufacturers have claimed that their announced sodium-ion cells perform better or at least as well as current LFP cells. The analysis carried out here shows that this is not the case.
So does this mean that the sodium-ion battery is a failure? Absolutely not! The motivation to switch to sodium-ion batteries is not to get a better cell. Instead, the chemistry convinces with low prices and a very good availability of raw materials. In the end, this can be more decisive than a slightly higher energy density.
Takeaway 4: Sodium-ion companies are already producing cells on a GWh scale - or will start in the next few years
Contrary to popular belief, sodium-ion batteries are not a distant technology of the future, but are already being produced on a gigawatt-hour scale by the first companies and made available to the first OEMs and partner companies. The first small electric vehicles are already on the market in China and the market will grow significantly over the next few years.
Although not all manufacturers have yet revealed when they intend to start mass production, many companies including BYD and Farasis have announced plans to build gigafactories. Sodium-ion cells are likely to achieve higher market shares in the second half of the 20s at the latest.
Takeaway 5: Many large companies are working on sodium-ion batteries - it will be difficult for start-ups
There are now almost 30 companies that are known to be working on sodium-ion batteries (click here for more information). If you look at the companies, you will notice that the vast majority have already developed lithium-ion cells in the past and have a great deal of experience in battery research. CATL and BYD in particular, with market capitalizations of $92 billion and $77 billion respectively, are financially very strong and therefore in a position to drive forward the introduction of new technologies. Accordingly, there are relatively few start-ups that are completely new to this sector. If you want to survive in this competition, you need to be well-funded, already have experience with batteries and have a technological innovation that sets you apart from other manufacturers – otherwise it is likely to be a hopeless battle.
