A new study from Stanford University says that sodium-ion batteries will need more breakthroughs in order to compete with lithium-ion (Li-ion).
Sodium-ion (Na-ion) battery technology is widely seen as the next to commercialise at scale and provide an alternative to lithium-ion (Li-ion). Recent news items covered by Energy-Storage.news about developments in sodium-ion technology include a BYD executive announcing the launch of a sodium-ion BESS product, Chinese and US firms announcing plans for sodium-ion gigafactories, and the world’s largest sodium-ion BESS coming online in China. vacuum baking oven
However, the new report from STEER, the US Department of Energy (DOE) funded organisation from Stanford focused on assessing the technological and economic impact of emerging energy technologies.
The study’s lead author, Adrian Yao, worked for eight years as the founder and CTO of Li-ion battery startup EnPower. Yao identifies 2022, the first time Li-ion battery prices rose, as an instigator for battery companies to explore sodium-ion manufacturing.
After the mid-pandemic price spikes, Li-ion prices reverted to their trend of declining and sodium-ion may be in a less strong position to overtake its market share.
Yao said of the situation: “We recognised that if, when, and how sodium-ion batteries might undercut lithium-ion on price was largely speculative, especially given that the price of lithium-ion continues to fall.”
According to BloombergNEF, global average Li-ion battery pack prices fell 20% in 2024, dipping below US$100/kWh for electric vehicles (EVs). This marks the biggest annual fall since 2017.
STEER’s study and the DOE’s 2022 energy storage supply chain analysis both highlight that there are dangers to relying on Li-ion only because it is a more affordable technology. There are also potential security risks. The study simulates what would happen if, for example, there was a supply shock to graphite.
Graphite serves as the anode in Li-ion batteries. Most graphite is mined in China, and the US has no current natural graphite production sites. China also began restricting exports of graphite and other battery and lithium processing related technologies to the US in 2024.
Turning to sodium-ion could be more advantageous in these situations, despite the technology’s current challenges with energy density, cycle life and performance.
There are alternatives to mined graphite, such as synthetic graphite, which the US still produces very little of. Other materials, like silicon, which can hold 10 times more lithium ions on a per-mass basis than graphite, are still in early stages, as noted by Callum McGuinn, partner at European intellectual property (IP) firm Mewburn Ellis for Energy-Storage.news (Premium access article).
The STEER study also notes that if lithium prices continue to decline over time, sodium-ion has a narrower set of technology routes to become price advantageous.
Yao added about the study: “One key thing we learned from industry practitioners is that while battery cell prices are important, technologies only succeed at the systems level – say, an electric vehicle or a grid-scale battery energy storage system.”
“That’s why we’re now expanding our scope to provide more holistic perspectives, including understanding the cost of safety and other systems considerations.”
Companies like US-based sodium-ion BESS startup Peak Energy are working to bring sodium-ion to large-scale projects and also believe it can be cost advantageous at smaller scales.
Speaking with Energy-Storage.news, Peak Energy president and CCO Cameron Dales said (Premium access article): “From a scale perspective, we believe that economics can support a profitable business even at a gigawatt hour or less at the cell assembly level.”
“It relies on the continuing growth of the overall material supply chain. That’s not something one company alone can drive to the point where it becomes cost advantageous to LFP.”
STEER compared Na-ion and Li-ion price trends in over 6,000 scenarios in its study. Through these scenarios, STEER concluded that Na-ion’s biggest challenge is increasing energy densities to decrease materials intensity.
As stated within the study: “The fastest and most certain way for Na-ion to be price advantageous is to reduce materials intensity by increasing materials and cell-level energy densities.”
“This is supported quantitatively in the parameter sensitivity analysis shown in Fig. 6, where some of the biggest drivers of forecasted Na-ion cell prices in 2030 and 2040 are accessible upper voltage cut-offs, cathode and anode specific capacities, and electrode thicknesses.”
heat sealing machine The full study by Adrian Yao, Sally M. Benson and William C. Chueh can be found here (PDF).