Solid state battery hits the market

[warshipadmin]

Some Chinese company, Contemporary Amperex Technology Co., Limited, announced a battery that gets to 90% charge in 7 minutes. LFP chemistry.

[Dagooz]

Some Chinese company, Contemporary Amperex Technology Co., Limited, announced a battery that gets to 90% charge in 7 minutes. LFP chemistry.

CATL is as far as I recall the biggest and most dominating manufacturer of EV batteries. They presented a number of new product updates this week.
Greater density, VERY fast charge times and sodium battery amongst them.
There is a link here for those interested, although I must admit I did not have the time to read it in detail:
https://cnevpost.com/2026/04/21/catl-un ... TRejLq_oqw

But overall, the advancements being done in existing tech makes me doubt that the solid state battery will have much of an advantage in the foreseeable future.

[Craiglxviii]

Some Chinese company, Contemporary Amperex Technology Co., Limited, announced a battery that gets to 90% charge in 7 minutes. LFP chemistry.

CATL is as far as I recall the biggest and most dominating manufacturer of EV batteries. They presented a number of new product updates this week.
Greater density, VERY fast charge times and sodium battery amongst them.
There is a link here for those interested, although I must admit I did not have the time to read it in detail:
https://cnevpost.com/2026/04/21/catl-un ... TRejLq_oqw

But overall, the advancements being done in existing tech makes me doubt that the solid state battery will have much of an advantage in the foreseeable future.

I’m now doing some work in the battery space.

Sodium batteries have around 30% of the inherent cell cost of Li-On, for about 72% of energy density. So they’re no good for cars but they’re really, really good for industrial scale battery storage systems.

Which is interesting.

[Belushi TD]

My company recently purchased two lithium iron phosphate batteries in place of deep cycle marine lead acid batteries.

They seem to work just as well, even in the deep cold we had here in February. Don't know about longevity, and won't for a few years.

The field guys LOVE them. They're about a third the weight of a lead acid, and that makes them FAR easier to schlep around in the woods where a lot of our wells are.

Belushi TD

[brovane]

My company recently purchased two lithium iron phosphate batteries in place of deep cycle marine lead acid batteries.

They seem to work just as well, even in the deep cold we had here in February. Don't know about longevity, and won't for a few years.

The field guys LOVE them. They're about a third the weight of a lead acid, and that makes them FAR easier to schlep around in the woods where a lot of our wells are.

Belushi TD

LFP Batteries are awesome. Recently built a 48V battery for my Golf Cart that I use on my property out of 16 3V LFP cells. Each 3V cell is 308AH and only cost me a little more than 4x12V batteries and I will probably never have to replace the batteries in my golf cart again.

[warshipadmin]

Did you have to get a new charger?

[Belushi TD]

Did you have to get a new charger?

Yes and no....

The battery has terminals and as I understand it, you can connect it to a regular 12 volt battery charger to charge it, as the battery contains the electronics to ensure it won't get damaged by incorrect charging. However, it charges differently than a lead acid battery (lots of info in the user manual that I don't have in front of me at the moment) and it charges much more efficiently using the plug in charger. I think the charger was 40 or 50 bucks, and the battery itself was 400? Or maybe two of them were 400? I don't recall the exact number. It worked out to twice the cost of a similarly sized lead acid battery, yes, but HR was thrilled at the idea of it weighing less and signed off on it.

It also has an on/off switch. Our new guy wasn't aware of that, and was in the field raging about how the f-ing battery was dead and f this and f that. When he called me to tell me the bad news, I asked him if he had turned it on.

He said "It has an on button?"

After a brief pause, he said "Ok, forget I called."

Belushi TD

[gtg947h]

LFP Batteries are awesome. Recently built a 48V battery for my Golf Cart that I use on my property out of 16 3V LFP cells. Each 3V cell is 308AH and only cost me a little more than 4x12V batteries and I will probably never have to replace the batteries in my golf cart again.

I put an LFP battery in my golf cart last spring. It's a single 48V block that weighs about 80lb, and replaces 400+lb of wet-cell lead acid batteries (and takes up about 1/3 of the volume). It came with a new charger that I integrated into the cart with a standard plug inlet. Now I can charge using any regular extension cord.

My parents just had a lithium conversion done on their cart; it ran two weeks late and they broke the headlights and horn from not hooking up the 12V converter right (it's now back at the shop getting fixed). Told them they should have brought it to my house

[brovane]

LFP Batteries are awesome. Recently built a 48V battery for my Golf Cart that I use on my property out of 16 3V LFP cells. Each 3V cell is 308AH and only cost me a little more than 4x12V batteries and I will probably never have to replace the batteries in my golf cart again.

I put an LFP battery in my golf cart last spring. It's a single 48V block that weighs about 80lb, and replaces 400+lb of wet-cell lead acid batteries (and takes up about 1/3 of the volume). It came with a new charger that I integrated into the cart with a standard plug inlet. Now I can charge using any regular extension cord.

My parents just had a lithium conversion done on their cart; it ran two weeks late and they broke the headlights and horn from not hooking up the 12V converter right (it's now back at the shop getting fixed). Told them they should have brought it to my house

With the way the supports in the battery box under seats was there was no room to fit a 48V block. We built 3 different wood boxes and then put the cells into the boxes, wired the batteries together along with a BMS. Don't have the charger integrated onboard.

PXL_20250330_205349021.MP.jpg

[Belushi TD]

Now that I'm back in the office, some interesting tidbits from the owners manual.

It specifically states NOT to use it to start a car.

It CAN be charged with an alternator or a generator, but it needs a DC to DC charger between the battery and the current source.

You can connect them in series or in parallel up to 8 units. Or at least that's the maximum they show in the manual. They recommend you disconnect them every 4 to 6 months to allow

Belushi TD

[warshipadmin]

... the electrons to have a rest?

[Belushi TD]

Now that I'm back in the office, some interesting tidbits from the owners manual.

It specifically states NOT to use it to start a car.

It CAN be charged with an alternator or a generator, but it needs a DC to DC charger between the battery and the current source.

You can connect them in series or in parallel up to 8 units. Or at least that's the maximum they show in the manual. They recommend you disconnect them every 4 to 6 months to allow "charges to stabilize"

Belushi TD

Bugger.... Computer didn't save the bolded text.

I assume that's translated and dumbed down electrical enginerd speak for "something overly complicated that means something along the lines of permitting charge densities inside each individual battery to level out in order to maintain battery health and life", but I am uncertain.

Belushi TD

[warshipadmin]

A subtle difference to lead acids. My charge controller holds them at 15V for a few minutes every few days, that's to equalise the cells, and floats them at 13.8V given the choice. Disconnecting them allows each cell to equilibrate, but can't do anything for the battery as a whole. There's a known effect in lead acids where the cell voltage picks up overnight if you don't use them, I suspect that's a similar chemical process.

[warshipadmin]

And an investigator is going to be cursed by 1300 small investors in the Donut battery https://electrek.co/2026/06/08/donut-la ... ion-fraud/

A comprehensive investigation by battery researcher Ziroth, involving over 20 independent battery experts, has produced what amounts to definitive proof that Donut Lab’s “miracle” solid-state battery is actually a lithium-ion cell. The company raised approximately $25 million from over 1,300 mostly small investors based on claims that now appear to be false.

The investigation traces the battery technology back to a German company called CT Coatings, reveals a web of companies hiding behind aggressive NDAs, and presents electrochemical evidence — including voltage curves and cell expansion data — that conclusively identifies the tested cell as lithium-ion, not the revolutionary sodium-ion solid-state chemistry Donut Lab promised.

From skepticism to confirmation

We have been covering Donut Lab’s claims with skepticism since the company shocked the battery world at CES 2026 with claims of a 400 Wh/kg, 100,000-cycle, 5-minute-charging solid-state battery. In January, I interviewed CEO Marko Lehtimäki and told him directly that he was either going to lose all his credibility or revolutionize the world. It looks like it was the former.

At the time, the incentives to lie weren’t clear to me, and the short timeline to delivery gave the claims some credibility. But as we tracked the independent testing results, the red flags kept piling up. Five tests from VTT and not a single one addressed the two claims that actually mattered: the 400 Wh/kg energy density and the 100,000-cycle life. Then came the whistleblower complaint from Nordic Nano’s former CCO, alleging the battery specs were never achieved.

Now, Ziroth’s investigation fills in the gaps with hard electrochemical evidence.


The evidence: voltage curves and cell expansion prove lithium-ion

The investigation consulted over 20 independent battery experts, including Julian Zanau from the Fraunhofer Research Institute, Dr. Yahim San from Justus-Liebig University, Tom Bicha from Leona, and Dr. Yuo Hesca from Seinäjoki University of Applied Sciences. Every single one confirmed the tested cell is lithium-ion.

There are two key pieces of evidence. First, the voltage curves from VTT testing match high-nickel lithium-ion cells (NCM chemistry). The cell sits at 3.7-3.8 volts at 50% state of charge — right where lithium-ion cells operate. Sodium-ion cells don’t go significantly past 3.5 volts at 50% SOC.

The second piece of evidence is even more damning: VTT’s cell expansion data. When a battery charges, ions squeeze into the anode material, causing it to expand in a predictable pattern. A graphite anode produces a distinctive “kink” in the expansion curve around 50-70% state of charge, caused by how ions reorder themselves in graphite’s layered structure. The Donut Lab cell shows exactly that kink.

This is critical because sodium ions are physically too large to fit into graphite layers. The graphite anode signature proves the cell uses lithium ions. The investigation puts it well: “it’s like we have a slightly noisy fingerprint and a picture of the suspect’s face. And yet again, it’s a match.”

The calculated energy density? About 298 Wh/kg — what you’d expect from a good lithium-ion cell, not the 400 Wh/kg claimed.

The web of companies behind the fraud

The investigation reveals that the battery technology traces back to CT Coatings, a German company with an “eclectic” array of patents — including inventions for screen-printed paving slabs, menu folders, and warning triangles. CT Coatings promised Nordic Nano and Donut Lab a screen-printed sodium-ion solid-state battery. What it delivered was a lithium-ion pouch cell.

The relationship works like this: CT Coatings was the technology provider, Nordic Nano was supposed to be the manufacturer, and Donut Lab was the commercializer. Nordic Nano has reportedly never manufactured a single battery cell.

Julian Zanau from Fraunhofer described meeting with CT Coatings representatives and being unimpressed: “The first impression I got was that these people have no idea how a battery actually works. They were talking about no rare earth metals in their batteries and therefore no lithium, and to any chemist lithium has nothing to do with rare earth minerals.”

Meanwhile, Donut Lab performed its own technical due diligence instead of getting independent validation — an approach that former Nordic Nano CCO Lauri Peltola described as deeply inadequate given that neither company had battery chemistry expertise.

Verge ‘production vehicle’ claim was verifiably false

Beyond the chemistry, the investigation documents clear-cut lies. Donut Lab claimed to have a production vehicle shipped to consumers in Q1 2026. On the last day of the quarter, they announced the “first production motorcycle” off the line.

But an internal video to reservation holders told a different story: the first bikes would be for Verge’s internal fleet, with the purpose of refining the manufacturing process before shipping to customers. That is, by definition, a pre-production vehicle.

In an interview with Finnish media, Lehtimäki then admitted that the 400 Wh/kg cells were not in the bikes and that the cell tested by VTT “is not even the cell that’s going to be shipped to customers.” Leaked emails showed Donut Lab asking CT Coatings when they would actually receive proof of the claimed specs. Apparently, no proof was ever provided.

$25 million raised from 1,300+ small investors

The most troubling aspect of the investigation centers on how the money was raised. Donut Lab has over 1,300 shareholders, with over 900 holding 50 or fewer shares — likely representing investments between $3,000 and $23,000 per person. Many came from a crowdfunding exercise on Finland’s Springvest platform in 2023 for Verge Motorcycles.

When Verge was restructured and Donut Lab was spun out, the company’s valuation jumped from a struggling motorcycle company to a parent company of a “half a billion euro portfolio” — all because of the miracle battery. An investor letter from Lehtimäki promised “a potential return on investment of up to 10x in just 12 to 18 months” and urged investors that “it is not yet too late to invest more.”

The investigation argues that this approach — using self-validated due diligence to raise money from investors who lacked the means to scrutinize the technology — was chosen deliberately to avoid the kind of technical scrutiny that venture capital firms would demand.

The valuation was later inflated to $1.25 billion after the CES presentation. Finnish financial authorities and criminal authorities are reportedly investigating.

In our interview with Lehtimäki in January, he claimed that he wasn’t raising money.

Electrek’s Take

We called this one early. When I sat across from Marko Lehtimäki in January and told him that he was either going to revolutionize the world or destroy his credibility, I still gave him the benefit of the doubt. The short timeline to delivery, the willingness to stake his reputation, the logic behind guarding the chemistry — it all made a certain kind of sense at the time. But the evidence is now overwhelming: the “miracle” solid-state battery was a lithium-ion cell, and the claims made to investors and the public were false.

[Paul Nuttall]

An update

https://cleantechnica.com/2026/09/04/do ... nce-tests/

Donut Lab revealed its solid-state battery to the world at CES 2026, to the amazement of many and to the dismay of others shocked by their achievement and performance claims. No other company has a practical fully solid-state battery in production as of this writing. Many, like Quantumscape, have tried for many years, only to find that limitations exist, like the need for extreme mechanical pressures required to maintain contact between cathode and electrode. Such measures require bulky and heavy support, obviating benefits of solid-state operation. Many have resorted to semi-solid-state as a compromise. Semi-solid-state batteries were used by NIO for battery swapping, but they ceased operation since cost and other practical factors proved unsatisfactory.

Not long after Donut Lab’s solid-state battery presentation, howls of derision and a cavalcade of insults and skepticism followed. Much of the criticism, unsurprisingly, came from established players in the battery market with vested interests in legacy batteries, companies which failed to produce a practical solid-state battery, proving Upton Sinclair’s dictum: “It is difficult to get a man to understand something, when his salary depends on him not understanding it.” Just because it is new and innovative does not mean it is real and it works, and it is prudent to request data. Some waited for data to decide, while others impatiently jumped to conclusions. In this case, in response to the many critics who said it was impossible and a scam, an unusual amount of proof beyond normal practice in the battery industry was provided. It’s not that large legacy battery makers do not provide proof. They usually provide data sheets carefully constructed to show their products in the best light for intended applications, and the boring engineering details are left in the background that show the limits. Nothing to see here, just the usual. They seldom provide such extended public proof, such as disassembly and extensive tests by independent testers.


Nail Tests

In particular with batteries, some tests are demonstrated to showcase best performance in a more dramatic way, like nail penetration tests. These are important tests and do show some of the safety attributes specific to different battery chemistries. Nail penetration and other safety tests are now standardized requirements for rechargeable batteries in China, a good development ensuring public safety and aiding battery use. Donut Lab’s battery was tested at 12V terminal voltage and then did nail penetration tests that showed absolutely no fire, smoke, or explosion and very little change in temperature, a very boring and safe result. NMC produces a more exciting display with flame and high temperatures, while LFP is less exciting and produces no fire, but some smoke. Sodium-ion batteries also produce unexciting nail tests. That set of Donut Lab tests also showed that the battery was bipolar, because the terminal voltage was above 12V and batteries with different numbers of layers showed several different voltages.


Incontrovertible Solid-State Proof

Good things are worth the wait, and Donut Lab has delivered new data. The latest tests prove the battery is solid-state and the measured gravimetric energy density is 409 Wh/kg. The volumetric energy density result is 804 Wh/l. Proof of solid-state was provided in several ways. The batteries can be made in bipolar format. That means the cells are stacked on top of each other within the package, producing a wide variety of external voltages depending on the number of cells within the package. This is impossible with a liquid electrolyte in one package. Liquid electrolytes can flow freely among all cells in the same package and ions can shuttle between multiple cells spoiling desired serial ion flow through each stacked cell. A solid-state electrolyte can stay in place between cell cathode and anode without providing a path for ions between other cells. A liquid electrolyte bipolar battery must provide separate isolated chambers for each cell electrolyte, making practical construction difficult and unwieldy. The advantage of bipolar construction is that current flows through a thin depth and over a large area, providing less resistance and requiring less electrode material than single cells constructed in a pack, increasing the ratio of active material and lowering costs. In pack construction, fewer modules are used and external conductors are reduced. The net effect is higher density at both battery and pack level, even comparing to cell-to-pack technology. In a remarkable demonstration, the cell was disassembled and showed internal construction consisted of repeated layers. There was no internal mechanical isolation between layers within the package. The layers are connected electrically by stacking. This leaves no doubt that the battery is bipolar and solid-state.


Social Media Got It Wrong

While I already recognized that liquid electrolyte NMC cells could not survive operation at 100°C undamaged, that was not enough proof for some that insisted it was an NMC cell. I debunked the notion that a cell produces a unique fingerprint by showing that other cells produced similar full charge and discharge open circuit voltages. Others have gone on to add to this. The unique fingerprint theory is wrong. It is possible to alter voltage characteristics by doping and other means. Bipolar operation brings into question whether the batteries previously tested were single cell or multiple stacked cells. Bipolar operation and disassembly show the connections create a single-stacked battery, an impossibility for a liquid electrolyte NMC battery. It cannot be assumed the previously packaged battery tested was a single cell. Despite all of this, incredibly, some have mistakenly concluded that there is no proof the battery is solid-state. They are wrong. Their conclusion that Donut Lab has no credibility is equally wrong and exposes their own credibility.


An Overlooked Matter and Story — Process

While solid-state construction and extraordinary battery performance gain headlines, process methods seem to gain little attention. I explained why the manufacturing process may be more revolutionary than solid-state operation. For those studying the field, it is no secret that printing has been a major focus for the solid-state manufacturing process. There are many studies on that. Investigations have shown that CT-coatings is the source of nano pastes used with silk screen printers. A process using nanopastes and printers may not require machinery in sealed vacuum chambers, removing toxic, flammable solvents like legacy liquid electrolyte lithium batteries do.

Donut Lab says its batteries also do not require formation. Formation is a last step in battery manufacture. Batteries undergo first full charge in this step. It forms the solid electrolyte interface (SEI) layer. Cells are warehoused in racks for up to a week, requiring large amounts of storage space. This step is the most expensive part of legacy battery manufacture. Together with the large sealed rooms and toxic vapor recovery, legacy battery manufacturing is achingly capital and operating cost intensive. Vapor recovery also requires large amounts of electricity. A 1 GWh factory can cost a billion dollars. By comparison, printed solid-state battery manufacture without expensive space-consuming formation and containment rooms is estimated to cost an order of magnitude less. Together with cheaper material costs than NMC, and easily sourced and widely available materials, printed battery manufacturing could pose a real threat to vested interests with huge sunk costs that are now in danger of becoming stranded assets. There are now several companies entertaining solid-state processing by the new printing method.


Conclusion and What is Next

From this, no conclusions can be drawn about what the cell chemistry is, but we can conclude the batteries can achieve over 400 Wh/kg and 800 Wh/l in packaged form, and are indeed solid-state, with other benefits — in all, a stunning performance result. So far, other performance claims have been verified, leaving only two important remaining performance claims unsupported, cycle life and -30°C energy retention.

The results seem anticlimactic after the rancorous critics’ responses, but there they are. It is beginning to look like critics that bet money may need to get out their checkbooks or wallets. The hoopla and pressure of social media clicks has subsided for a while. We will see whether critics own up. No doubt, some critics will persist even when shown to be wrong. The battery has proved to be solid-state, not a legacy NMC battery, and bipolar capable. Bipolar operation was not a focus early on. We are awaiting demonstrations of low temperature operation and cycle life, but now that the other claims have been proven, the battery is already remarkable. I don’t think competitors can sleep easy waiting for the final tests. There may be considerable agitation and acrimony in boardroom meetings upon hearing the latest news. I expect the industrial spies will be out in droves after this, if they are not already. It is too late to tamp down interest in this battery with disparaging rumors. Things are getting serious. There is too much proof. The test results matter. There is a real battery with astonishing performance. The ramifications of these test results deserve sober consideration.

[Nik_SpeakerToCats]

Remarkable claims require remarkable evidence: Do you reckon they've delivered ??

Also, are we beginning to see a backlash upon the nay-sayers ??

I'm reminded of the AC Clarke Law which wryly observes:
The only way of discovering the limits of the possible is to venture a little way past them into the impossible.

[warshipadmin]

measured gravimetric energy density is 409 Wh/kg

For comparison lead acids are around 30 Wh/kg, my shiny new LIFePo batteries are about 140 (in cases, the Donut number is for bare cells no doubt).