Are Sodium-Ion Batteries the Future of Storage Technology in the U.S.?

An alternative grid-scale battery energy storage technology that could operate more safely and economically — and require less maintenance over a longer life span than the one that now predominates — is poised for an initial thrust into the U.S. commercial power generation and distribution market.

Peak Energy, Broomfield, Colo., announced Nov. 12 that it will furnish the sodium-ion battery technology it is refining to Jupiter Power, a six-year-old Austin, Texas-based firm that is an emerging player in the utility-scale battery power storage sphere.  

The agreement calls for Peak to deliver its product to Jupiter over a potential three-year period beginning with a firm initial 720MWh slug in 2027. After that, if an option is exercised, it could provide another 4 GWh of storage through 2030 that would bring the total contract value to more than $500 million. The deal, Peak claims, marks the largest single deployment so far of sodium-ion batteries and comes just three months after it deployed its first unit at a Colorado test facility and began a pilot test of its system with nine utility and independent power producer customers.

The new storage technology will be delivered at a time when Jupiter will presumably be expanding its footprint. Its website indicates it has several projects in operation, largely sited in Texas, where it claims to be the deployment leader with state utilities, and that it has 12,000MW in development in some 30 states.

In a Peak news release a Jupiter executive indicated the deal would position the company to be an early adopter of a technology that could be a “potential game-changer for the industry,” as well as a pillar of support for domestic battery storage manufacturing.

Sodium-ion phosphate pyrophosphate (NFPP) technology is seen as a possible leading successor to lithium-ion, the one that has captured most of the worldwide battery market. The focus of Peak when it was founded in 2023 by executives from Tesla and other battery companies, the technology has the potential to address many of the problems and deficiencies that are coming to light with lithium-ion, supporters say.

High on that list is fire risk. Lithium-ion batteries used in battery energy storage systems (BESSs), and other applications, have shown themselves to be susceptible to combustion and resulting fires have proved deadly in some cases and hard to bring under control. A feature of sodium-ion batteries is a lack of components needed in lithium-ion batteries, ones Peak says are “implicated in the vast majority of battery storage system fires analyzed by independent third party reports.” The company says its battery architecture eliminates all moving parts, including those needed for cooling and ventilation, resulting in complete elimination of the “most common failure modes in typical battery storage systems.”

A test publicized in a recent posting on Batteries News, however, called into question sodium-ion battery safety. German researchers discovered that one it tested produced “an almost explosive reaction” when it was pierced with a metal pin to trigger a “critical damage event.” But it traced the reaction not to the battery’s chemical composition but rather its venting system. “Our results do not call into question the fundamental safety of sodium-ion technology, but they underscore the need to consider chemical composition and safety design together,” a researcher was quoted as saying.

Another benefit of the simplified architecture of sodium-ion batteries is greater operational reliability and latitude. The batteries, Peak says, require less maintenance and produce lower operational costs, and because they can operate in a wider range of temperature conditions the need for auxiliary systems to regulate that factor is reduced. It all adds up, potentially, to an energy storage system far less demanding and needy than one employing lithium-ion battery technology.

Sodium-ion batteries could also be an answer to the growing challenge of global materials sourcing. Rather than relying on lithium supplied from non U.S. sources, sodium-ion battery chemistry requires the mineral precursor, soda ash, a product in great abundance domestically. Refining the technology and commercializing it could mean more batteries are produced entirely in the United States, Peak says. With domestic power generation, transmission and distribution demands growing, more U.S.-based battery production to supply the new and increasingly important component of energy storage could prove critical. Sodium-ion technology could prove to be the answer to both challenges.