The Donut Story Continues.

[beatle]

It sure looks like nice testing by an independent lab, but I'll hold onto my checkbook for now.

They shove a lot of energy into that battery very quickly without it blowing up, using only a couple of heatsinks for cooling. What's more, they slammed it at 11C for the full length of its charge cycle. Some of the latest Chinese LFP EV batteries can briefly take 10C, but then start to taper off as they approach 50% SoC or less - and that's using liquid cooling.

Some important stuff that's still missing: how many times can you do that before the cell degrades or destroys itself? They mention that typical battery chemistries are quickly killed by high C-rate charging, but they mention nothing about how long their own battery will last. This only shows that it survives the test.

The test also talsk about thermal stability. VTT actually stops the first 11C test because it topped 90C:

The first attempt was interrupted when the surface temperature reached the safety limit of 90 °C.

But Donut says this is "still very much in the comfort zone of this cell."

And what about low temperature performance? The presenter also admits the "sweet spot of the donut battery cell is in the more hot environment."

 

[NowThatsDamp]

Guys this test is even more meaningless than I thought it would be.

Looking more and more likely that some folks may have to eat their words. I hope that turns out to be true.

The better this turns out the better for those of us that are all in on EV’s.

Actually the exact opposite is supported by this video.

The only launch claim attempted to be verified by this first video is "This pack charges from zero to full in as low as 5 minutes". Timestamp 13:16 in the launch video.

They ordered lab tests that were specified to make the pack look as good as it possibly can. The results?

This pack does not charge from zero to full in as low as 5 minutes. It charges from 0 to 80% in as low as 5 minutes, and with two big catches. You take a brutal 18% hit to your charging efficiency and you will cook the battery trying without a very very robust cooling system.

Charging time is not a debate anymore. They tried prove the claim that is the lowest hanging fruit on a long list of bold promises. The black and white results came back and they are undeniable: Launch event claim on charging time is fact check false.

Next.

 

[The Weatherman]

Guys this test is even more meaningless than I thought it would be.



Actually the exact opposite is supported by this video.

The only launch claim attempted to be verified by this first video is "This pack charges from zero to full in as low as 5 minutes". Timestamp 13:16 in the launch video.

They ordered lab tests that were specified to make the pack look as good as it possibly can. The results?

This pack does not charge from zero to full in as low as 5 minutes. It charges from 0 to 80% in as low as 5 minutes, and with two big catches. You take a brutal 18% hit to your charging efficiency and you will cook the battery trying without a very very robust cooling system.

Charging time is not really a debate anymore. They tried prove the claim that is by far the easiest to prove of the long list of bold promises. The black and white results came back and they are undeniable: Launch event claim on charging time is fact check false.

Next.

I’m sorry your cup is always half empty.

I will give them the benefit of the doubt until it shown to be untrue.

A smart person once said: “Live in Hope or Die in Despair.”

 

[NowThatsDamp]

I will give them the benefit of the doubt until it shown to be untrue.

They literally just showed it to be untrue beyond any doubt.

 

[The Weatherman]

Here’s the take from a Canadian EV enthusiast I have followed for several years now.

Just another prospective.

 

[AZFox]

Our fellow member @MiketheCarGeek did a perspective piec too.
Good job, Mike.
Donut Solid State - Test #1 Charging Performance

 

[bartflossom]

https://electrek.co/2026/02/23/donut-lab-vtt-solid-state-battery-test-results-fast-charging/

 

[NMNeil]

Supposedly the 'battery' on show at CES was a 3D printed model that nobody was allowed to handle. No research papers, no patents.
But for me the biggest red flag is that they the big boys; GM, Ford etc haven't already done a deal with them. So far only https://www.wattelectricvehicles.com/ https://covapower.com/
and https://esoxgroup.com/ have partnered with Donut Lab.
But here's something telling. In the EU they have to state all sorts of specs for batteries, and they plan to use those solid state batteries in the Verge motorcycle, but give no details at all, just 'Information coming soon'
https://www.vergemotorcycles.com/et_en/battery-information/
Until I can put down money and actually buy one for myself; I'll sit on the fence.

 

[KevinRS]

Apparently the charging speed was the least controversial of their claims, other batteries can be charged that fast. They claim it can be used with no active cooling, but the testing showed that single cell needed 2 heatsinks.
The charging cycles claims are a big one, they claim 100k cycles, that's not proven at all yet, other solid states have only reached low thousands at most. 400 Wh/kg in combination with those 2 are where experts say the claims go way beyond credibility.

 

[bloo]

Capacitors charge fast. That's what they do. Being electrostatic, they don't have to go through the electrochemical conversion true batteries do.

I'm more interested in capacity at a scale that can move a car. If Donut can do that, they've won.

 

[KevinRS]

Capacitors charge fast. That's what they do. Being electrostatic, they don't have to go through the electrochemical conversion true batteries do.

I'm more interested in capacity at a scale that can move a car. If Donut can do that, they've won.

Are they claiming it's capacitor based? From what I find, solid state batteries are still lithium batteries, with lithium ions moving between the plates, just through a solid electrolyte instead of a liquid one. Still electrochemical, just without the liquid.

 

[bloo]

I had thought this was a type of supercapacitor holding an electrostac charge. Donut hasn't exactly given us much. Come to think of it, neither has Slate.

Anyhoo... when I first heard about Donut, I immediately thought "supercapacitor." Do you know if it isn't one?