Both , external and , external filed for bankruptcy and there are fears in Europe that the continent has missed another technology shift.
With more transport and industry switching from fossil fuels to electricity, batteries are likely to be a growth business.
But the length of time required to bring new products to market, coupled with brutal competition, especially from China, means taking a substantial risk.
Could the answer lie at an almost unimaginably small scale? An increasing number of investors and researchers think so.
A single nanometre is one-billionth of a metre, but it's at that level that some of the most consequential work is being done.
"If you can make this work, it touches so many industries [but] it's a risky business," says Christian Rood, chief executive of Dutch tech firm LeydenJar.
Named after a 18th century precursor to electric cells, LeydenJar uses a technique known as plasma deposition to make a lighter, more efficient anode – an essential component of all batteries.
Silicon is a highly effective and cheap material to use in anodes, but pure silicon expands and contracts as the battery operates and is recharged, which causes it to crack.
However, using plasma deposition, LeydenJar can - layer by tiny layer - make an ultra-thin pure silicon foil which resists cracking, allowing a significant increase in battery life, charging speed, and energy density (up to 50%, according to LeydenJar).
"Where normally a pure silicon anode would fall apart, [this] remains stable, so it was a very wonderful invention," says Rood.
"We address the bottleneck in the battery. "
It's no coincidence that LeydenJar's factory is in the Dutch city of Eindhoven - home to ASML and other important players in the computer chip industry.
"A lot of people talk theoretically about ecosystems; I can tell you this is one of our sources of competitive advantage," Rood says.
"It's really the crossover from semiconductors to batteries that makes us different - once you've demonstrated the principle in the lab, industrialization requires you to work with the semiconductor technology and suppliers.
"That means a lot of risk, but also a lot of opportunity in terms of patenting, in terms of securing your whole intellectual property. And that's much more difficult to do in the US or in China. "
Across the Netherlands and Europe more widely there are multiple smaller Deep Tech start-ups looking to develop nanotechnology in the battery market.
One of those is Powall, a start-up in the Dutch city of Delft that is developing commercial-scale equipment for nanocoating the powders that are the raw materials of today's batteries.
Again, the scale is tiny, and once again the technique was born in the semiconductor industry.
Individual powder granules are measured in micrometres, the coatings in nanometres - they are applied using a technique known as atomic layer deposition.
Roderik Colen, CEO of Powall, tells me that the system offers multiple opportunities to adjust and improve the performance of today's batteries.
"Your battery works less well than before after using it thousands of times - that degrading or aging can be slowed down when you're using a nanocoating," Colen explains.
"You can have an exciting new material with a higher capacity or fast charging, all these novel developments. They typically have one element which is very good, but they suffer on the durability side. "
And that means they will never be a commercial product.
"That's where we then come in, to give them the protective coating to effectively enable these new materials. "
The powders and the coating are carried by gas and brought together in a chemical reaction.
It is, says Colen, a precise but flexible process which can be almost endlessly adapted.
"You have great accuracy in how thick you want to have it. And that makes a difference in performance. "
But Christian Rood of LeydenJar says companies like his can fortify Europe's position in what has become a global contest.
"The easy comparison is with semiconductors, where there's really a race for the best chip technology.
"[Dutch tech giant] ASML is not producing chips; it focuses on a critical step in the production of chips, and in that way, has a seat at the table when it comes to the whole semiconductor battle.
"This is our ambition as well – to have a position where our battery anode is so unique that we have an important position in the supply chain. "
So, how do these ambitions play into Europe's goals in the battery industry?
Alexander Brown is a senior analyst at the Berlin-based independent think-tank the Mercator Institute for China Studies (Merics).
"I think having one part of the supply chain based in Europe is great and if that can be a very advanced technological part, which offers the opportunity for high margins, that's fantastic," Brown tells me.
But he cautions that while "there can be collaboration as well as competition at the same time", China in particular will continue to work to reduce its dependence on other regions.
"China is working very hard to develop local alternatives for technologies, including these niche technologies.
"It's no secret that China would love to replace ASML - they're working very hard to do that, and it's not unforeseeable that they will achieve that goal eventually.
"So, I think Europe has traditional strengths in developing very exquisite high-quality products, which can find markets all over the world.
"But I also think it's important for that not to be the only strategy [from the continent's policy makers]."
The challenges of working in such a specialised field are not only technological.
LeydenJar has already reached commercial scale, but Rood says that raising funds within Europe is not always easy.
"There is sufficient financing in Europe, but the risk attitude is quite different than in Asia and in the US," says Rood.
"That means for a company like us that you have to work with different sources of funding at the same time," Rood explains.
He lists government grants, debt financing, help from the European Investment Bank and investors willing to buy a share of the business.
"They set a lot of challenging conditions, and they all want to do their own due diligence. It's hard work," Rood says.
Powall's Colen says Europe, and the Netherlands in particular, is an "innovation powerhouse", and battery technology offers a chance for the continent to make an impact, if the appetite for the risk is there.
"It's a relatively young industry where factories are being built left, right and centre. They're searching for the right tech. So that's where you can play a big role, because the volumes are huge. "
Perhaps Europe's place in that business lies not in building huge battery gigafactories, but at the other end of the scale altogether.
As Colen puts it, "small changes make big differences. "