Skip to main content

The biggest battery in the world could be in a salt cave in Germany

Caves aren’t just homes to giant bat colonies — thanks to modern technology, they can also house batteries. And not just any batteries — the world’s largest battery. A few weeks ago, German utility EWE unveiled its plans to build an energy storage system in an old salt mine that could ultimately become the biggest battery on Earth.

The ambitious new project has been named “brine4power,” and will take form in underground salt caverns that were previously natural gas storage facilities, and even further back in history, were salt mines. All these caves have a volume of 3.5 million cubic feet, which ought to give the resulting battery a capacity of up to 700MWh at an output of 120MW.

Recommended Videos

So how would the battery work? The massive undertaking would depend upon redox flow technology (which involves filling these caves with a lot of saltwater). These types of batteries work by storing energy as liquid electrolytes. A positive catholyte and negative anolyte are kept apart by a membrane that only lets ions pass through.

When the battery is charging, the ions move to the anolyte, and when it’s discharging, the ions move back to the catholyte. Charged molecules are then pumped into a storage tank, where the energy can be kept safe for future use for months at a time. And the cool thing about the brine4power system is that it stores the electricity in liquid form. While it certainly takes up a lot more space, it’s also pretty powerful — if it works, this salt cavern battery ought to be able to supply 75,000 homes with their power for a day.

“We need to carry out some more tests and clarify several issues before we can use the storage principle indicated by the University of Jena in underground caverns. However, I expect that we will have an operating cavern battery by about the end of 2023,” says Ralf Riekenberg, head of the brine4power project.

If things go according to plan, EWE Managing Director Peter Schmidt says the battery could “fundamentally change the … market for control energy. The amount of electricity this kind of storage facility contains — consisting of two medium-sized caverns — is sufficient to supply a major city such as Berlin with electricity for an hour. It means that we will have built the world’s largest battery.”

Lulu Chang
Fascinated by the effects of technology on human interaction, Lulu believes that if her parents can use your new app…
The Ioniq 5 is once again eligible for the $7,500 tax credit
2025 Hyundai Ioniq 5

After a brief and confusing absence, the Hyundai Ioniq 5 is once again eligible for the full $7,500 federal tax credit — and this time, it's sticking around (at least for now). So, what happened? Let’s unpack the ride.

The Ioniq 5, a sleek and tech-savvy electric crossover, initially made headlines not just for its design, but for being built at Hyundai’s brand-new Metaplant in Georgia. That domestic assembly qualified it for the EV tax credit under the Inflation Reduction Act (IRA), which requires vehicles to be made in North America with batteries sourced from trade-friendly countries. But early in 2025, the Ioniq 5 vanished from the list. Why? Likely due to its battery packs, which were then still being sourced from SK On’s Hungarian facility.

Read more
Sebastian Stan lays out Bucky’s future after Thunderbolts
Sebastian Stan in Thunderbolts.

There are some spoilers ahead for the ending of Marvel's Thunderbolts. Stop reading now if you don't want to be spoiled.

Earlier this year, Captain America: Brave New World briefly introduced a new direction for James "Bucky" Barnes, a character Sebastian Stan has been playing since 2011 in Captain America: The First Avenger. In Brave New World, the former Winter Soldier apparently retired from being a reformed hero and went into politics by running for Congress. Thunderbolts reveals that Bucky won his election to the House of Representatives. But his stay in Congress was short.

Read more
Jeep Compass EV breaks cover—but will it come to the U.S.?
jeep compass ev us newjeepcompassfirsteditionhawaii  4

Jeep just pulled the wraps off the all-new Compass EV, and while it’s an exciting leap into the electric future, there's a catch—it might not make it to the U.S. anytime soon.
This is a brand new electric version of the Jeep Compass, and being built on Stellantis' STLA platform—the same architecture underpinning models like the Peugeot E-3008 and E-5008—it looks much slicker and packs a lot more inside than previous versions of the Compass.
Let’s start with what’s cool: the new Compass EV is packing up to 404 miles of range on a single charge, a 74 kWh battery, and fast-charging that gets you from 20% to 80% in about 30 minutes. Not bad for a compact SUV with Jeep's badge on the nose.
There are two versions: a front-wheel-drive model with 213 horsepower and a beefier all-wheel-drive version with 375 horsepower. That AWD setup isn’t just for looks—it can handle 20% inclines even without front traction, and comes with extra ground clearance and better off-road angles. In short, it’s still a Jeep.
The design's been refreshed too, and inside you’ll find the kind of tech and comfort you’d expect in a modern EV—sleek, smart, and ready for both city streets and dirt trails.
But here’s the thing: even though production starts soon in Italy, Jeep hasn’t said whether the Compass EV is coming to America. And the signs aren’t promising.
Plans to build it in Canada were recently put on hold, with production now delayed until at least early 2026. Some of that might have to do with possible U.S. tariffs on Canadian and Mexican vehicles—adding a layer of uncertainty to the whole rollout.
According to Kelley Blue Book, a Stellantis spokesperson confirmed that the company has “temporarily paused work on the next-generation Jeep Compass, including activities at” the Canadian plant that was originally meant to build the model. They added that Stellantis is “reassessing its product strategy in North America” to better match customer needs and demand for different powertrain options.
So while Europe and other markets are gearing up to get the Compass EV soon, American drivers might be left waiting—or miss out entirely.
That’s a shame, because on paper, this electric Jeep hits a lot of sweet spots. Let’s just hope it finds a way over here.

Read more