How water could make safer batteries

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I’d be prepared to wager that you simply in all probability haven’t spent a lot time desirous about the liquid that sloshes round inside batteries. 

But this liquid—referred to as the electrolyte—is certainly one of their key elements, and it dictates quite a bit about how they work, in addition to how protected they’re. And I’ve seen a rising variety of various battery makers speak about utilizing an fascinating ingredient of their electrolyte: water. 

Lithium-ion batteries that energy EVs and laptops right this moment have to make use of natural solvents like ethylene carbonate to shuttle cost round (we’ll get into the main points on why later). But chemistries that make it potential to depend on water as an alternative could imply even safer batteries. And as we put extra batteries to make use of in giant storage programs on the grid, that could be a serious profit. 

I not too long ago wrote about one various battery maker referred to as Eos, which received an enormous mortgage from the US Department of Energy final week.  So for this version of the e-newsletter, let’s dive into how Eos and different battery makers want to change up battery chemistries with water. 

A scorching subject: battery security

It will be difficult to speak about lithium-ion batteries and security, as a result of there’s loads of misinformation on the market and feelings can run scorching. But it’s price digging in right here on why so many different battery makers emphasize security after they speak about their expertise. 

Lithium-ion batteries can and generally do catch hearth, often after they’re broken or after they get too scorching, kicking off chemical reactions in a course of referred to as thermal runaway. Devices that use lithium-ion batteries sometimes have security programs in place to handle this danger: electrical autos have cooling programs put in round battery packs, for instance. 

But generally issues can go incorrect. Manufacturing defects occur (keep in mind these Chevy Bolt fires?). It’s not completely clear how usually EVs catch hearth generally, although some information suggests it’s a lot much less usually than gas-powered autos. But alternatively, EV fires can burn hotter than fires in standard automobiles, and they’re more durable to place out. 

The query of security could develop into an much more essential one as we begin to use batteries in a brand new manner: on the ability grid. As we set up extra renewable power on the grid, there’s a rising want for large-scale power storage installations that may save solar energy to be used at evening, as an illustration. 

These storage programs are nice information for chopping emissions, however issues can go incorrect with them as nicely. As Canary Media reported, New York has seen just a few battery fires this summer season in large-scale stationary storage installations on the grid. No accidents have been reported in any of the fires, and injury was principally restricted to the batteries themselves. But a string of fires doesn’t look too nice. 

There’s additionally rising concern about fires began by e-bikes in New York City. These fires, which will be lethal, have principally been brought on by bikes that aren’t repaired appropriately or use substandard batteries, highlighting the necessity for regulation and tight high quality management of batteries. 

What it comes all the way down to is that this: lithium-ion batteries can catch hearth. It doesn’t occur usually, and there are a lot of, many security controls that may be put in place to handle the danger successfully. But some battery makers wish to construct alternate options that can’t catch hearth within the first place. 

Watering it down

Lithium-ion chemistry has been optimized over many years to pack loads of power right into a small, light-weight system and ship loads of energy. 

Part of that optimization is within the liquid electrolyte: normal lithium-based batteries use natural solvents blended with salts to shuttle cost round. Theoretically, batteries can use water because the solvent, however they often don’t. That’s for a fairly good cause: the excessive voltage frequent in lithium-ion batteries, which is required to ship excessive energy, can pull water aside into hydrogen and oxygen. 

But in relation to large storage installations on the grid, there’s a special steadiness to strike. Rather than specializing in packing a number of power right into a small battery, researchers and firms need above all to decrease the batteries’ price.  

So batteries destined for storage on the grid can make some compromises. They won’t must cost and discharge so shortly, and it’s much less essential to get them as small and lightweight as potential. 

That opens up the potential of utilizing heavier supplies, like iron and zinc. And with decrease energy and decrease voltages wanted, corporations can use water with salts blended in as an electrolyte. That could assist save on prices, make the batteries simpler to fabricate, and likewise assist with security. You’d in all probability have a tough time setting water-based batteries on hearth, even in the event you tried. 

Some corporations are leaning into the advantages of utilizing water of their various batteries as they begin to make progress towards commercialization. 

Form Energy is among the leaders in constructing various batteries for the grid. The firm’s batteries are generally referred to as “rust batteries” as a result of they use iron and water, and the reactions are much like those that occur steel rusts with publicity to moisture. Form’s web site touts its batteries’ security, saying the programs have “no risk of thermal runaway.” The firm broke floor on a manufacturing unit in West Virginia earlier this yr. 

Eos Energy can also be constructing batteries with a water-based electrolyte, utilizing zinc as a major cathode ingredient. When I requested Francis Richey, Eos’s VP of analysis and growth, what the advantages of the corporate’s chemistry have been, the very first thing he introduced up was security: “Number one, it’s safe. It’s a non-flammable technology.”

There are loads of challenges forward for various batteries, like the issue of competing on value: lithium-ion cells have been round for many years, and prices have plummeted in that point. But there are potential upsides to having extra choices—together with workhorse programs that could ease security considerations about giant battery installations. 

Related studying

Read extra concerning the Department of Energy’s mortgage to Eos Energy, and the way the corporate’s zinc batteries work, in my newest story. 

Iron batteries on the grid have been on our 2022 record of Breakthrough Technologies—see why on this blurb from final yr.

Sodium-ion batteries will be constructed with electrolytes based mostly on both water or natural solvents. And many battery specialists are intrigued by this various chemistry for each EVs and stationary storage programs. 

It’s not straightforward bringing a battery startup into the world, although. Read extra concerning the rise, fall, and rebirth of sodium-ion battery maker Aquion in my colleague James Temple’s story from 2017. 

Another factor

If you haven’t registered for Local weatherTech but, I’ve received one other nice cause so that you can change that: we’re revealing a particular mission on the occasion this yr. 

The Tech Review local weather crew has been laborious at work placing collectively an inventory of 15 corporations to look at in local weather tech. These corporations span all kinds of sectors, and so they come from all over the world. I can’t give anything away simply but, however you would possibly acknowledge just a few names in the event you’re a longtime reader of this article …

Join us on MIT’s campus or nearly on October 4-5 for the primary have a look at the record, together with a ton of thrilling conversations concerning the expertise, coverage, and enterprise of local weather. Hope to see you there! 

Keeping up with local weather  

New factories for EVs and their batteries are popping up throughout the US South. Some of them could rework small cities—like this Ford manufacturing unit underneath building close to a 400-person city in Tennessee. (Wall Street Journal)

→ My colleague David Rotman took a detailed have a look at how $100 billion funding in laptop chips could have an effect on Syracuse, New York. (MIT Technology Review)

The US Environmental Protection Agency was publishing warnings about local weather change 40 years in the past. It’s fairly wild how correct they have been on all the pieces from how a lot warming was anticipated to how a lot varied applied sciences would possibly assist. (The Messenger) 

Two digital energy vegetation simply got here on-line in Texas. Clusters of small batteries can be utilized to fulfill demand on the grid, although this system is fairly small proper now. (Canary Media) 

If you embrace plug-in hybrids, the title of world’s largest electric-vehicle maker goes to a Chinese firm referred to as BYD. And now, the corporate is attempting to broaden past China’s borders. (Rest of World) 

→ Here’s how China got here to dominate the world of EVs. (MIT Technology Review)

A gaggle of researchers signed a letter calling for extra analysis on ocean-based carbon elimination efforts. While these strategies could assist suck carbon out of the ambiance, there are questions on each how nicely they may work and the way they’d have an effect on ecosystems. (The Verge)

Fertilizer is a large local weather downside. Some startups wish to change that, although there’s some skepticism about how nicely replacements would possibly carry out. (Canary Media)