Does Climate’s Future Depend on Better Batteries?

April 14, 2021

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China hosts more than two-thirds of the world's megafactories making lithium-ion batteries, the kind that power Teslas. Above, a worker for the Chinese carmaker Geely Auto, which announced a new line of electric vehicles earlier this spring. Photo: Geely Auto. Click to enlarge.

Backgrounder: Does Climate’s Future Depend on Better Batteries?

By Joseph A. Davis

I just want to say one word to you. Just one word.

No, not plastics.

The word is “batteries.”

Batteries are the key to the energy transition and the planet’s climate future. And there’s lots of progress here to report on.

While non-polluting energy sources like wind and solar don’t always produce electricity at the times and places where people need it, if that energy can be stored to be used when and where demand occurs, then carbon-free energy becomes more viable.

Batteries are also crucial to electric vehicles, which can make use of clean energy if it can be stored in transportable form.

Batteries have gotten better in recent years — but further improvements are needed. Entrepreneurs, companies and nations are racing to win the tech competition and market dominance.


The companies souping up batteries

could make billions and the nations hosting

them could dominate the world economy.


The prize may be vast — the companies souping up batteries could make billions and the nations hosting them could dominate the world economy — and so too will be the pleasure of helping save the planet. So it’s a subject that environmental journalists may need to follow closely.


Tesla’s battery magic

A few decades ago the lead-acid battery in your car, or the zinc-carbon dry cell in your flashlight, was the pinnacle. Not any longer.

When Elon Musk wowed the world in 2006 with his new Tesla cars, which ran the zero-to-60 drag race in under two seconds, ran on laptop batteries and came in the color red, it seemed like hotness had gone green.

Tesla was not just making zippy red roadsters. Tesla was making batteries. Tesla’s original magic was the lithium-ion battery — the same technology that powers most laptops. It’s light, compact and powerful.

But even that technology is still being tweaked and supercharged. Today, battery technology is seeking new frontiers. 

Back then, Musk quickly announced the construction of a “gigafactory” for batteries near Reno, Nevada, with more planned. Since going into the car business, Musk had snapped up home-solar leader SolarCity in 2016. Musk was also selling the Powerwall, a fridge-sized Li-ion battery that can charge off a house’s solar panels or the grid, and can back up a house’s power during grid outages, or just do load-leveling.


Assessing energy storage

To risk simplifying some very complex and varied technology, most batteries work via the process of electrolysis. Two terminals are immersed in an electrolyte, a substance that can store electrical energy in chemical form.

In a lithium-ion (Li-ion) battery, lithium ions move from one electrode to another when it charges — and back the other way when it discharges. For our purposes, which focus on batteries’ use for green energy, we will ignore the one-use (e.g., flashlight) batteries and look just at rechargeable ones.

The characteristics of a battery matter a lot. Cost, for example, is crucial to commercial success. Ease of manufacture is closely related — Musk’s genius seemed to fall in this realm.

Scalability is another quality that is critical for industrial applications. Availability of raw materials (like lithium) is another key. Government R&D funding and other subsidies are also critical, especially in this new and highly competitive market.

But it is in the tweaking of the engineering and chemistry of batteries where the sharpest competition is taking place these days. While the basic principles of electrolysis don’t change much, refinements in materials and construction techniques are the battleground.

For example, the lithium-sulfur battery, which adds sulfur to the electrolyte, shows promise of performance beyond the basic Li-ion. These are not yet commercially viable. The Solar Impulse, the solar-powered airplane that flew around the world, used batteries with a lithium nickel manganese cobalt, also known as NMC, chemistry. Yet another promising battery technology for certain applications is based on zinc-oxygen (or zinc-air) chemistry.


Battery qualit(ies) count

Whether you are flying a solar plane or driving a plug-in roadster, you want your batteries to be light and compact — but still powerful enough to keep you going.

A battery’s specific energy is the amount of energy it can store per unit of mass. Its energy density is the amount of energy it can store per unit volume. These qualities don’t matter so much if you are storing electricity for a utility power grid. In fact, large arrays of the old-fashioned lead-acid batteries (the kind found in your car) have been used for utility storage.

There are plenty of other qualities to be sought in an electric battery. Don’t you hate it when your cell phone’s battery runs down to where its capacity to hold a charge is inadequate in barely a year or two?


Some batteries keep their capacity longer

than others. This matters a lot if your precious

plug-in roadster is losing its driving range.


Some batteries keep their capacity longer than others — although most will die after enough charging cycles. Some batteries’ capacity depends on how deeply you discharge them. Some just age.

This matters a lot if your precious plug-in roadster is losing its driving range, the distance it can go between charges. It’s not just a matter of longevity. There is always a trade-off between the amount a battery can store and its size and weight.

Charging time is another key variable for battery systems. Most batteries take a while to charge up. This may not matter too much for grid-attached batteries. But car-owners are used to pulling into the gas station, filling up and getting back on the road in minutes.

Until recently, the best uses for electric cars were as town cars or in delivery fleets that could charge overnight. Tech advances more recently have made fast battery charging feasible in certain circumstances, with special charging stations.


The greening of stored energy

Enough technical stuff. Here’s more to think about: In some circumstances, electric batteries may not necessarily be the only (or best) way to store energy.

One example on the utility front is pumped storage. Electricity is used to pump water uphill into a reservoir, and then, when it is needed later, it is released downhill through turbines that generate electricity for the grid. Of course, not every place has the water or hills needed for this.

Another storage method is found in solar concentrating towers, which develop high temperatures and store energy in molten salt. Neither method will work for your roadster.

Then there’s hydrogen. Today, those who sell stock in initial public offerings are pushing it as a miracle cure. Before you buy their stock, however, reflect that it almost always takes some energy input to create hydrogen.

One method, for example, uses electrolysis to disassemble water molecules into hydrogen and oxygen. You can also get it by reforming the methane in natural gas.

If the electricity comes from a truly renewable source like wind or solar, they may be justified in calling it “green” hydrogen. The input electricity, though, may not be green. Hydrogen may be converted to energy by combustion or — better yet — by fuel cells. Fuel cell cars have already been prototyped.

So think of hydrogen as another way to store electricity. Remember, too, that hydrogen’s flammability makes it tricky to store. Think Hindenburg.

But despite all the dreams of green technology, a battery alone will not solve the climate crisis. What matters more is the source of electric power charging it. It is not green if it is being charged by coal or gas, only carbon-free sources like wind, hydro or solar.


GM out front, but China leads

The bad news is that the United States may already have lost the battery race and the electric car race. China seems to be eating our lunch.

If you blinked, you may have missed the backstory. Barely two years ago, with President Trump egging them on, U.S. carmakers seemed to be spending all their energy (at least a good chunk of their lobbying and advertising budgets) trying to resist Environmental Protection Agency standards for reducing their greenhouse gas emissions (notably carbon dioxide) from internal combustion engines.


Biden’s advent had a lot to do with

GM announcing that it was going

all-electric by 2035. But the market

had already begun a sea-change.


This year, after the election and the Biden inauguration, General Motors (may require subscription) announced that it was going all-electric by 2035. Or, in today’s parlance, zero-emission (may require subscription). The auto industry, to paraphrase Rep. Debbie Dingell (D-Mich.), turned upside down.

Yes, Biden’s advent had a lot to do with it. But the world automobile market had already begun a sea-change. This is how the New York Times’ Neal E. Boudette and Coral Davenport (may require subscription) put it: “Wall Street investors think Tesla is worth more than General Motors, Toyota, Volkswagen and Ford put together.” Other carmakers, in subsequent weeks, followed GM’s lead.

But there’s also China, which some perhaps were too timid to mention during the Trump years. China was already headed down the electric vehicle road. Just three months before the GM announcement, China announced plans to switch to mostly electric or hybrid new car production by 2035. This may have influenced GM even more than the election.

China is the biggest market for new cars in the world. And China actually started down the plug-in/hybrid path more than a decade ago (may require subscription). Of the 142 Li-ion megafactories under construction worldwide, 107 are in China. Tesla itself has been making cars and batteries at a gigafactory in Shanghai for at least a year.

But the electric cars the Chinese buy will not, for the most part, be $200,000 Tesla roadsters. Instead, they are likelier to be $4,320 bare-bones models (may require subscription) meant for the masses. But Teslas are selling in China.

The thing is: Despite Tesla’s pedal-to-the-metal rush into the battery market, China is actually dominating the worldwide Li-ion battery market right now. And as (or should we say if) U.S. carmakers and drivers move toward electric vehicles, that, as the Times’ Keith Bradsher writes (may require subscription), could well put China in the “driver’s seat.”

Joseph A. Davis is a freelance writer/editor in Washington, D.C. who has been writing about the environment since 1976. He writes SEJournal Online's TipSheet, Reporter's Toolbox and Issue Backgrounder, as well as compiling SEJ's weekday news headlines service EJToday. Davis also directs SEJ's Freedom of Information Project and writes the WatchDog opinion column and WatchDog Alert.

* From the weekly news magazine SEJournal Online, Vol. 6, No. 15. Content from each new issue of SEJournal Online is available to the public via the SEJournal Online main page. Subscribe to the e-newsletter here. And see past issues of the SEJournal archived here.

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