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Super-hot salt could be coming to a battery near you

There’s a lot going on in the climate world. Election workers are still counting and recounting votes in the US to determine tenancy of Congress, and at the UN climate conference, delegates are heads-down in negotiations, rival over climate targets and finance agreements.

We’re still waiting for increasingly information well-nigh what these hair-trigger moments will midpoint for the future of climate policy and technology. While I alimony my ears out for increasingly definitive insights into what it all means, let’s take a unravel from the speculation and swoop deep on something I think we should all be talking well-nigh more: batteries.

I’m obsessed with batteries, and I’m unchangingly watching the wave of volitional chemistries that’s slowly percolating into the growing energy storage market. Some of these new players could sooner be cheaper (and in various ways, better) than the industry-standard lithium-ion batteries, but they often squatter real barriers to adoption. So let’s take a squint at one startup’s journey to store energy using super-hot salt.

Why we need new batteries

The world is towers increasingly topics for renewables, expressly solar and wind power that come and go with the weather. So, long story short, we need to be worldly-wise to store energy. (I went increasingly into this a couple weeks ago in the newsletter, trammels that out here if you missed it.)

Pumped hydropower rumored for over 90% of worldwide energy storage as of 2020. While hydro is a cheap, constructive way to store power, it comes with environmental concerns and major constraints on where it can be installed, since it requires large persons of water.

Batteries make up most of the rest of today’s energy storage capacity, and will likely worth for the zillion of energy storage market growth as well in the coming decades. Today, lithium-ion batteries are most common, similar to the ones in your phone or electric vehicle.

Over decades of minutiae and scaling, lithium-ion batteries have gotten cheaper, and production topics has exploded, with new shower Gigafactories popping up all virtually the world seemingly every other week.

But there are a few mismatches between lithium-ion’s strengths and what’s needed in batteries used for stationary energy storage.

  • Price: Grid-scale storage needs to be dirt-cheap to help renewables be affordable. Last year, the US Department of Energy set a goal of reducing financing by 90% by 2030. Lithium-ion batteries have gotten cheaper over the years, but gains may be plateauing, expressly with possible material shortages expected.
  • Size: Lithium-ion batteries pack a lot of power into a small space. But while shower size is important for things like phones and cars, it’s not so crucial for grid-scale energy storage. Compromising on energy density for stationary applications could midpoint lower cost.
  • Lifetime: Industrial plants often put in equipment that, when maintained, lasts for decades. Lithium-ion batteries typically need to be replaced every 5-10 years, which can be pricey.

How hot salt can help

With the mismatch between lithium-ion batteries and our future energy storage needs, it seems like everybody is working on an volitional way to store energy. In just the last year, I’ve covered iron air and iron spritz batteries, plastic ones, and plane one startup using compressed stat dioxide to store energy.

Now, flipside technology is making the jump from the lab to the commercial world: molten salt.

Ambri is a Boston-area startup that’s towers molten-salt batteries from calcium and antimony. The visitor recently announced a sit-in project deploying energy storage for Microsoft data centers, and last year it raised over $140 million to build its manufacturing capacity.

The visitor says its technology could be 30-50% cheaper over its lifetime than an equivalent lithium-ion system. Molten salt batteries can moreover exceed 80% efficiency, meaning that a relatively low value of energy that’s used to tuition the shower is lost to heat.

Ambri was founded in 2010 based on research from Donald Sadoway’s lab at MIT. The goal was to develop a low-cost product for the stationary storage market, says David Bradwell, the company’s founder and CTO.

The inspiration came from an unlikely place: aluminum production. Using similar chemical reactions to what’s used for aluminum smelting, the team built a lab-scale, low-cost energy storage system. But turning this concept into a real product hasn’t been so straightforward.

The magnesium and antimony-based chemistry the visitor started out with proved difficult to manufacture. In 2015, without standing issues with the batteries’ seals, Ambri laid off a quarter of its staff and went when to the drawing board.

In 2017, the visitor pivoted to a new tideway for its batteries, using calcium and antimony. The new chemistry relies on cheaper materials, and should prove simpler to manufacture, Bradwell says. Since the pivot, the visitor has worked out technical glitches and made progress on commercialization, going through third-party safety testing and signing its first commercial deals, including the Microsoft one.

The Microsoft energy storage system. Image courtesy of Ambri.

There are still major challenges superiority for the startup. The batteries operate at upper temperatures, over 500°C (about 900°F), which limits what materials can be used to make them. And moving from single shower cells, which are well-nigh the size of a lunchbox, to huge container-sized systems can present challenges in system controls and logistics.

That’s not to mention deploying a product to the real world ways “dealing with real world things that happen,” as Bradwell puts it. Everything from lightning strikes to rodents can throw a wrench in a new shower system.

At least one thing has reverted over the last decade though: the market. Investors and plane unstudied observers used to push when on whether everyone would want energy storage, Bradwell says. Now, the only question seems to be how quickly the industry can grow.

It will take time for Ambri and other new shower outfits to scale manufacturing and prove that they’ll be a viable, affordable volitional to existing batteries. As Bradwell says, “the journey continues.”

Keeping up with Climate

Disagreements well-nigh climate goals are hanging over COP27, the UN climate conference. Some leaders want to reaffirm the need to alimony warming to 1.5°C, plane as the target seems to be slipping out of reach. (New York Times)

Delegates at COP27 are still deep in talks over loss and forfeiture funding for climate transpiration impacts. (Bloomberg)

→ If you missed it, trammels out last week’s newsletter for increasingly on why this funding is at the part-way of the talks.

The US is working to cut the influence of China in climate tech manufacturing. But the move could make some technologies increasingly expensive and slow progress on climate goals (Grid News)

→ Meanwhile, the US and China are restarting climate talks. (Washington Post)

Republican gains in the US midterms were limited, quelling some renewable energy advocates’ concerns that Congress would dismantle recent climate action. (Inside Climate News)

The electric revolution has two wheels. Well-nigh 40% of motorcycles and other smaller vehicles sold last year were electric, a much higher fraction than larger passenger vehicles. (Protocol)

We’re getting a largest idea of AI’s climate impacts. Researchers ripened a new tideway to understand emissions from large language models, which require a huge value of energy to train and run. (MIT Technology Review)

Organic solar cells are getting better. The technology could unshut up new applications for solar, since organic cells are light and flexible, but they’ll need to moreover be durable and easily-manufactured to unravel into the market. (Science)

Electric trucks are coming, bringing with them wild requirements for the grid. By 2035, a truckstop could require as much power as a small town. (Bloomberg)

Grids may be worldly-wise to handle fleets of short-haul wordage trucks, but long-range trucking poses a greater challenge. (MIT Technology Review)