Salt storage battery

That includes California-based Inlyte Energy, which has just completed a successful test of its full scale “salt battery,” aimed at pushing fossil fuels out of the power generation business.

A New Sodium-Based Energy Storage System, Supported By The US Department Of Energy

This year’s abrupt shift in federal energy policy brought much misfortune upon the US wind and solar industries, especially in the offshore wind area.

However, Li-ion remains the best fit for portable and short-duration applications.

Market & Policy Tailwinds (2025-2030)

• U.S. Corrosion resistance, thermal management, and electrode stability remain ongoing challenges.

  Molten Salt Battery vs Lithium-Ion: Which Energy Storage Tech Wins in 2025?

  When comparing molten salt batteries (MSBs) with lithium-ion batteries (Li-ion), the key differences revolve around cost, safety, duration, and scalability.

  Feature	Molten Salt Battery	Lithium-Ion Battery
  Operating Temperature	200-600°C	15-60°C
  Energy Density	Lower (80-120 Wh/kg)	Higher (150-250 Wh/kg)
  Safety	Non-flammable	Fire risk under stress
  Duration	6 to 24+ hours	1 to 4 hours typical
  Cost	$9-$50/kWh (projected)	$100-$200/kWh (current)
  Scalability	Ideal for grid-scale	Ideal for mobile devices/EVs

  Winner? For grid-scale storage and long-duration power needs, MSBs outperform Li-ion on cost, fire safety, and thermal stability.

  In addition to Southern Company, the other partners at launch included the utility Alabama Power, the Southern Research branch of the University of Alabama, the state of Alabama, and the Electric Power Research Institute as well as Energy Department and its Oak Ridge National Laboratory in Tennessee.

  “The facility will offer a resource for the industry to test and develop energy storage technologies needed to better integrate renewable energy into the power grid, as well as improve reliability and resiliency, while creating more value for customers,” Southern Company explained in a press release dated July 26, 2019.

  The Rise Of The Sodium EV Battery

  No word yet on whether or not Inlyte is interested in transferring its technology over to the EV field.

  Buckle up—this isn’t your typical battery PR fluff.

  12V 200Ah Sodium ion Battery

  What Are Salt Water Batteries?

  Definition and Basic Chemistry

  At their core, salt water batteries are a type of aqueous battery that use a saltwater electrolyte—think of ordinary water infused with salt—to shuttle ions between electrodes during charge and discharge.

  The plan involves testing the new iron-sodium energy storage system in the UK, at a facility located in the Derby area, as a step towards the launch of a manufacturing facility in the US.

  While that plan was under way, in June Inlyte received a $4 million award from the CiFER (Critical Facility Energy Resilience) program of the US Department of Energy, to support the installation of its long duration energy storage solution at the Alliance Redwoods health care campus in Occidental, California.

  In September, Inlyte also announced the next steps in its transition from R&D to commercial application, including a partnership with the leading US utility Southern Company aimed at demonstrating a utility-scale version of its technology in Alabama.

  Long Duration Energy Storage Really Is Coming For Your Fossil Fuels

  So far, all has gone according to plan.

  

  Inflation Reduction Act (IRA) and EU Net-Zero Industry Act provide 30-50% capex subsidies.

• Curtailment of renewables is rising; in California alone, over 2 TWh of solar was curtailed in 2023.
• Storage mandates: U.S. targets 90 GW by 2035, India aims for 50 GW by 2030.
• Flammability concerns are steering utilities away from Li-ion toward thermally stable MSBs.
• Commercial buyers now demand 24/7 clean energy, requiring 10- to 12-hour storage systems.

Six Breakthrough Innovations to Watch

Economics: Levelized Cost of Storage Outlook

• 2024: Li-ion LCOS = $0.14-$0.18/kWh-cycle; MSB demo = $0.03-$0.06/kWh-cycle
• 2030 projection: With a learning rate of 18% and scaling to 5 GWh, MSBs could reach $0.02/kWh-cycle

A typical MSB system also benefits from:

• High round-trip efficiency (75-85%)
• Non-flammable operation (lower insurance & safety costs)
• Modular design suitable for both grid and industrial co-gen applications

Deployments & Case Studies

1. Ambri & Xcel Energy (Minnesota, USA): 1 MW / 4 MWh pilot focuses on multi-day thermal cycling and degradation studies.
2. Reliance Industries (India): Building a 150 MWh solar-integrated salt battery plant near Gujarat.
3. Nordic Heat Battery (Denmark): Using MSB-derived tech for 10-hour heat storage powering 100,000 homes via district heating.

Image source : sulzer.com

Denmark’s Gigawatt-Scale Molten Salt Battery: A Turning Point in Thermal Storage

In 2024, Denmark unveiled one of the world’s most ambitious molten salt battery (MSB) projects—a 1 GWh thermal energy storage system in the coastal city of Esbjerg.

A 200 MWh version of the system under construction in Holstebro will reduce Arla’s reliance on natural gas by 50% and cut energy costs by over €3 million annually.

Global Significance:

This Danish breakthrough underscores how MSBs can help solve two major challenges: long-duration energy storage and industrial heat decarbonization.

Saltwater batteries stay cool and calm even if something goes wrong. If you have enough space, care about sustainability, and want a set-it-and-forget-it system for 15 years, saltwater batteries are worth the extra upfront cost.

Stick with lithium-ion if space is tight or budget is your main concern. Notably MIT published a prototype MSB with a cell cost of $9/kWh in 2024 vs $120/kWh for standard lithium-ion batteries.

But since they last longer and need no maintenance, the total cost over 15 years might be similar or even less.
✗ Aren't many manufacturers yet: The technology is still growing, so you have fewer choices and might wait longer to get your system installed. Its iron-sodium formula is scalable to more than 48 hours, though the company states that it can also economically deliver electricity to fit daily 4-10 hour cycles.

But for fixed storage where safety and sustainability are king? It will never dethrone lithium for everything — but it might just become the go-to solution when lithium’s flaws become too costly to ignore.

FAQ

Are Salt Water Batteries Really Safe?

Yes. When the battery charges, ions are pulled out of the electrolyte and tucked into the electrode.

✓ Completely recyclable: When your saltwater battery reaches the end of its life in 10-15 years, every single part can be recycled safely. At four hours, that’s about the same as Li-ion technology but without the need for fire risk mitigation.

Research into sodium-based EV batteries and other energy storage systems devices dates back to the 1980s, though commercial applications proved elusive until a series of breakthroughs occurred in the early 2000s.