Last month, on the high prairie east of its hometown, Denver-based Peak Energy powered up what it says is the United States’ first grid-scale sodium-ion battery installation and “the first ever fully passive megawatt-hour scale battery storage system” anywhere in the world.
Peak’s 3.5-MWh project marks a big step forward for the electrochemical battery chemistry that many experts believe is the most viable challenger to lithium-ion, which today dominates the energy storage market for discharge durations shorter than four hours.
“What’s nice about our technology is the way it looks and feels to a customer is like a new variant of a [lithium-ion battery] system,” said Landon Mossburg, CEO and cofounder of Peak Energy.
Sodium-ion batteries’ allure is growing amid volatile commodity pricing and an on-again, off-again trade war between the United States and China affecting lithium-ion batteries.
Sodium-ion storage has a simpler supply chain that eschews traditional battery metals, said Evelina Stoikou, an energy storage analyst with BloombergNEF. The U.S. has the world’s largest known reserves of soda ash, a sodium precursor that is more abundant globally than lithium, nickel and cobalt.
“Lithium-ion costs remain highly sensitive to raw material prices, meaning that spikes in lithium, nickel, or cobalt prices could improve sodium-ion’s relative competitiveness,” she said.
But Stoikou cautioned that swingy raw materials pricing can cut in the other direction. At the moment, rapidly-falling LFP costs are driving a boom in global lithium battery deployments.
“Expectations among [sodium-ion battery] manufacturers have cooled as LFP prices continue to trend downward, leading to a reduction in our expectations for sodium-ion to scale,” she said.
Sodium-ion proponents like Peak Energy believe sodium-ion chemistry, though less energy-dense than lithium, has inherent advantages that will allow it to compete on cost before the decade is done. Those include lower fire risk, higher discharge rates, more efficient thermal management and better performance in extreme hot and cold conditions. Mossburg estimates his batteries cost 20% less to operate over 20 years than an equivalent lithium-ion system.
China charges ahead on sodium-ion
As debate rages over sodium-ion batteries’ place in the global energy mix, sodium-ion battery manufacturers and developers are moving forward — particularly in China.
In fact, Peak’s groundbreaking Colorado installation also looks puny next to recent sodium-ion deployments in the world’s second-largest economy. One Chinese state-owned power company is developing a 100 MW/200 MWh installation. Another recently commissioned a 200 MW/400 MWh hybrid sodium/lithium facility that it says reduces system costs by 30% over a sodium-ion-only equivalent. Industry analysts and insiders credit the advancements to the Chinese government’s supply-side subsidies and product standardization.
Stoikou said that Much of the know-how and production for sodium-ion batteries is concentrated in China [and] initial deployment of new-generation sodium-ion products will continue to be in China.