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Energy
News
Sodium-Ion Batteries Get Another Shot at Success in the U.S.
General Motors backs the latest effort to catch up to China
Lawrence Ulrich
22 Jul 2026
6 min read
Lawrence Ulrich is an award-winning auto writer and former chief auto critic at The New York Times and The Detroit Free Press.
Peak Energy, with significant backing from General Motors, believes it can succeed with its sodium-ion batteries where other U.S. startups have failed.
Lucas Breuer/Peak Energy
Despite setbacks in sodium-ion battery development in the U.S., the startup Peak Energy says it can be the one to finally achieve the ambitious application of using the tech to store energy for the grid.
When U.S. start-ups Natron Energy and Bedrock Materials shut down sodium-ion battery operations last year, they joined an ignominious list of more than dozen failed Western battery companies.
CATL, based in China and the
world’s largest battery company
, then dropped a bombshell in April, announcing it would supply 60 gigawatt-hours of sodium-ion cells to the grid storage provider HyperStrong. The largest sodium-ion battery order in history suggested China was on its way, as with
lithium-iron phosphate in previous years
, to dominating yet another promising chemistry.
The Colorado-based Peak Energy insists it can succeed where companies like Natron failed. Company executives say its sodium-ion tech can compete directly with low-cost lithium-iron phosphate (LFP) batteries, which currently dominate grid storage. Unlike Natron, which
ran out of money and investors’ patience
, Peak Energy has a giant in its corner: General
Motors
. Like Tesla and other automakers, GM is moving aggressively into grid storage to keep massive battery factories humming in the wake of slumping EV demand.
Peak Energy has formed a partnership with the automaker to ultimately deploy sodium-ion batteries at grid scale. In July, the company announced it will build a
US $71 million, 17,000 square-meter factory
near Sacramento, with capacity to produce 4 GWh of sodium-ion batteries annually, enough to power 4 million homes.
Sodium-Ion vs Lithium-Iron Phosphate Batteries
As with other sodium-based designs, Peak Energy’s cells can’t yet match the energy density of LFP batteries. Company executives from Peak Energy and GM, which has partnered with Peak to
codevelop and manufacture
the batteries, freely admit they can’t currently compete with current LFP prices on a per-cell basis.
Yet Peak Energy says its passively cooled storage system will still cost operators 20 percent less over its lifetime compared with LFP storage. Cameron Dales, Peak Energy’s cofounder and chief commercial officer, says the company’s
GS1.1 system
will store energy for 20 years, over roughly 20,000 cycles, and still retain 80 percent of its capacity. For LFP, a basic
durability benchmark
pegs them at 70 percent capacity after 8,000 cycles.
Peak Energy’s case is helped by a booming market for energy storage, to back up AI data centers and to store excess solar and wind energy. Volatile lithium prices have major players looking for a steady alternative.
Incumbent LFP batteries, Dales says, were initially designed for EVs, where cell costs and energy density are critical for driving range and affordability. But utilities and storage operators are focused on entirely different metrics. They want batteries that last the longest, at the lowest overall cost, to maximize returns and justify massive capital investments.
The company’s technical edge, Dales says, is that its stable cells that can operate safely at temperatures roughly double the typical operating temperatures of LFP, which performs
best at or near room temperature.
“You need to keep an LFP cell at 25 °C, give or take, or it will rapidly degrade,” Dales says.
The generous temperature tolerance of Peak Energy’s cells allows a passive cooling system with no pricey, trouble-prone fluid cooling loops or moving parts such as fans or pumps. That makes the modular system well-suited for data centers or grid support in desolate areas, where operators are finding abundant cheap land, high potential for solar energy, and a low risk of natural disasters.
“You don’t have to power a refrigerator in the desert for 20 years to keep the system operating properly,” Dales says.
The GS1.1 system stacks slender prismatic cells into modules roughly the size of a king-size mattress. A 36-module system stores 3.1 megawatt-hours. Large-scale projects might combine dozens or hundreds of units, generating enough juice to power a small city.
Proponents note that sodium is the
sixth-most abundant
element on earth, roughly
1,000 times as abundant as lithium
. And unlike lithium, which must be sourced from
far-flung regions
fraught with environmental or human-rights issues, the world’s largest, purest deposits of trona are found in the
Green River Basin
in Wyoming. Trona, which is composed of sodium carbonate, sodium bicarbonate, and water, supplies the
United States
with 90 percent of its soda ash, which is the basis for battery-grade lithium carbonate salt. However, analysts note that while the raw material may be plentiful, its processing is dominated by China.
“The supply chain tends to get overlooked, but it’s just a massive issue,” says Varnika Agarwal, a battery research analyst at Benchmark Mineral Intelligence.
Agarwal says sodium-ion tech holds promise. But a lot has to go right for sodium ion to carve out a viable niche in the U.S. Benchmarks project that less than 1 percent of newly deployed storage in the United States will be sodium ion this year, less than 4 percent by 2030, and 5 percent globally.
For now, she notes, Peak Energy is buying its commercial cells via contracts with Chinese suppliers, which dominate both processing of its raw materials—however cheap-and-abundant they may be—and cell production. The U.S. is basically just getting started, with Peak Energy’s California factory slated to come online in 2027.
NFPP Cathodes in Sodium-Ion Batteries
Natron was banking on
long-shot “Prussian Blue”
electrodes, a form of blue pigment that acts as a sponge to
soak up and release sodium ions
. Peak’s batteries, however, rely on sodium iron pyrophosphate (NFPP) cathodes, which are chemically and structurally similar to lithium-iron phosphate in an LFP battery, known for superior safety and
long cycle life
.
NFPP is fast becoming an industry standard. CATL has also settled on NFPP for its core chemistry. This helps make Peak Energy’s cells largely “drop in,” able to be manufactured at existing battery plants such as GM’s—a huge advantage for market viability.
Kurt Kelty, Tesla’s former battery guru and a globally recognized battery expert, is now vice president of batteries and sustainability at GM. Kelty says GM is backing Peak Energy for several reasons, including his familiarity with and respect for its own former Tesla execs.
Peak Energy executives [from left] Landon Mossburg, Kurt Kelty, and Cameron Dales show off one of the company’s prismatic cell batteries.
Lucas Breuer/Peak Energy
GM has been testing Peak Energy’s cells, in 170 and 190 ampere-hour formats, at its Wallace Battery Cell Innovation Center in suburban Detroit, in the same labs where GM is developing its proprietary
lithium-manganese-rich battery chemistry
. Kelty says the battery life of competing cells, from a full range of global producers, “falls off a cliff” during high-temperature testing. But Peak Energy’s batteries are withstanding extreme testing at up to 55 °C, with notably little effect on their lifespans.
“The cell is kicking butt over everything,” Kelty says. “We can get 20 years of lifetime without a cooling system, and that’s the key.”
The batteries are showing a round-trip efficiency of 96 percent, a significant 2 to 3 percent better than LFP. (“
Round trip
” refers to the amount of energy a battery discharges, relative to the amount used to charge it).
Eliminating active cooling, Kelty adds, allows a near-silent system that could be used in public buildings. In addition, it ditches the plumbing that’s a potential trouble spot for leaks and maintenance.
“It also reduces parasitic power losses, because you’re not using power to cool the system,” Kelty says.
Peak and GM executives believe sodium-ion cells themselves will reach price parity with LFP around 2028, based in part on discussions with Chinese cathode suppliers. Sodium ion, they say, is just entering its steep slope of cost reductions, where LFP’s savings have largely been realized over 20 years.
Peak Energy’s Sodium-Ion Battery Projects
In March, Peak Energy announced it will join with
RWE Americas
for another pilot system near Milwaukee. That would become the first-ever use of sodium-ion backup on the
Midcontinent Independent System Operator,
the regional grid operator for 15 central states and Canada’s Manitoba province.
Peak Energy also plans to begin supplying up to 4.75 GWh of batteries to
Jupiter Power
, an independent storage developer, through 2030. The deal, worth up to $500 million, includes an initial 720 MWh of storage, including in Texas, the nation’s largest single announced deployment of the batteries to date.
Ask Dales about winners and losers in battery chemistries, and he’ll tell you it’s the wrong question. In a world of planes, trains, phones, drones, and every imaginable device, it makes no sense that one “super battery” would rule them all.
“Sodium ion is just another sister technology to lithium,” he says. “But instead of going higher energy density, it’s going lower energy density, and you’re paying for that with better stability and safety at a lower cost.”
This story was updated on 23 July, 2026 to correct the timeline for Peak’s California facility. It is scheduled to come online in 2027, not 2028 as originally stated.
From Your Site Articles
Sodium-Ion Batteries Poised to Pick Off Large-Scale Lithium-Ion Applications ›
Here’s a Peek at the First Sodium-ion Rechargeable Battery ›
Natron’s Failure May Not Spell Doom for Sodium-Ion Batteries ›
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sodium-ion
batteries
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Lawrence Ulrich
Lawrence Ulrich
is an award-winning auto writer and former chief auto critic at
The New York Times
and
The Detroit Free Press
.
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