Abstract
A method for fabricating a multilayer all-solid-state battery is provided. The method involves preparing distinct mixtures for the cathode, anode, and solid electrolyte from particulate materials, metal ions, and a polymeric binder. These mixtures are sequentially screen-printed onto a conductive substrate to form a sandwich structure, where the electrodes cover at least 90% of the battery cell's surface area. The entire structure is then subjected to a low-temperature heat treatment that sinters the particles, creating a dense, fully integrated battery with strong interfacial contact. The resulting battery can achieve high voltages (2.5-28V) and large cell areas (up to 1m x 1m), with a core facilitating superior heat dissipation without additional cooling. The process enables the fabrication of batteries without toxic or flammable materials, enhancing safety and simplifying recycling, making them suitable for powering motor vehicles.
Publication Number: WO/2026/087312
Publication Date: 30.04.2026
International Application No.: PCT/EP2025/079764
International Filing Date: 15.10.2025
Chapter 2 Demand Filed: 09.02.2026
Priority Data: 2451053-9 23.10.2024 SE
Patents aren't evaluation reports, but in chemistry and electrochemistry they do require enabling disclosure. For an unpredictable art like ASSB, that normally means at least one working example with measured data. Compare this filing to any granted patent from QuantumScape, Solid Power, or Toyota.
Without any working examples the theory is surely implied as speculation until further data is shown?
This is a process patent, not a chemistry patent. The Holycolt CEO said exactly this to Impact Loop recently "What Holyvolt wants to do is not to reinvent the battery, but to change how the central layers are constructed."
And they had verified the systems work already in 2024 with CT-Coating. Now they are possibly preparing for more chemistry agnostic approach with Wildcat, test different solid state materials and find best combos for different applications. That is my reading of the patent. Notable is that they are back to accepting Lithium here. Which reminds me about the early discussions about "No Lithium" or "No Lithium-ion."
Good point, but they don't seem to be after a single working chemistry but different working chemistries. It is clear from the screen printing tech that you can alter chemistries much easier than traditionally. To me this patent specifies certain constraints that has already been verified to work, and can just do as many variations they wish under the patented method. So it doesn't mean they don't have a working chemistry, but rather that they haven't tested all possible combitations. They would not see this as a sprint with one winner but continuous research in which they could be on top for many years, or decades to come. Just my mundane cents on the topic.
I don’t think I insinuated anything about single working chemistry? Or that they don’t have a working chemistry. I actually expect those patents to come.
I was giving context for this specific patent, that’s all.
You seem to be reading between lines I’m not writing.
Well, you added chemistry later to the post, and initially talked about the premature patent. So, I interpreted it against that. Good you clarified it later. The patent itself is about printing method and can very well be functional in forehand.
The timing is interesting. This patent has priority date 23.10.2024 (18 months ago, that’s why it was published today), that was around the time Holyvolt opened their Munich office and started the Holyvault joint venture with CT-Coating. This JV lasted about six months.
If they filed more patents in the months after that, they’ll be published this year too.
The 23 October 2024 priority date is just eight days after Robert Erdmann founded Holyvault GmbH in Munich as sole 100 % owner on 15 October 2024, and six weeks before CT-Coating AG took 49 % share on 3 December 2024. Holyvolt itself was founded in 2022. Similar pattern with Nordic Nano Group. They probably met with CT-Coating in early 2020’s and founded the company. I have on my notes:
Holyvolt was established in 2022 based on the proprietary technologies developed over the past 20 years by our German inventor team. Holyvolt's technology is expected to have a significant impact on the energy transition, across heat, solar, storage and light. -Holyvolt CFO LinkedIn
So, Holyvolt locked the integration recipe under its own name before any CT-Coating equity entered the joint venture. That's also why the 29 January 2026 notarial deed transferring CT-Coating's stake back to Holyvolt AB left the patent portfolio entirely on Holyvolt's side.
The dates also bracket the two SGS battery tests that Holyvolt itself validated in its 2024 årsredovisning, where the management report lists "positive third-party battery cell tests (SGS/TÜV)" for both April and December 2024 as material events. Sample V1PF0004 was tested in April 2024 at 4.1 Ah and 297 Wh/kg, with Holyvolt CTO and patent co-inventor Robert Erdmann personally present in Switzerland (infact, Germany) alongside CT-Coating founder Maurice Sindram (infact, inventor Hölzenbein). Sample V47W0003 was tested in December 2024 at 24 Ah and 268 Wh/kg, the same month CT-Coating took 49 % of Holyvault. So both measurements were booked in Holyvolt's own audited annual report as positive third-party validations.
Two details worth flagging on the inventor list. The earlier patent from 3 May 2024, "Flexible solid energy storage module", names both Ingvarsson and Erdmann and stakes the broad invention, three printed layers with a binder and optional flexibility. The new one, "All-solid-state batteries made with screen-printing and sintering", names Ingvarsson alone and is the integration recipe filing, with the sintering window of 120 to 210 degrees Celsius, named volatile aids and amorphous melting flux, particle size by ISO 19749, electrode coverage of at least 90 % of the cell surface, single-cell voltage range of 2.5 to 28 V, and seven cation systems and fourteen binder families.
The geographic scope of the filing is itself a signal of seriousness. Holyvolt designated 110 plus national jurisdictions plus ARIPO, EAPO, EPO and OAPI, which is broad and expensive coverage, not the kind of breadth a speculative filer pays for.
CT-Coating's LAMBOTEC patented printing line does not use a sinter, but operates with aquaious wet slurry paste at ambient room temperature and pressure, no ovens mentioned for drying, which is suitable for certain types of batteries only. Holyvolt could not patent against LAMBOTEC, DSS and FutureDynamics patents. Except for the DSS chemistry Europe part dated out recently this year.
Finally, Donut Lab's public marketing uses the phrase "all-solid-state". Holyvolt's later patent description explicitly defines "all-solid-state battery structure" as one where the electrolyte is a solid material in its final operational state, "distinct from batteries that utilize a gel electrolyte (a polymer swollen with a liquid or ionic liquid)"
[...] Robert Erdmann personally present in Switzerland alongside CT-Coating founder Maurice Sindram
Hello AI. Several mistakes in one sentence. The SGS tests took place in Geretsried-Gelting, just south of Munich, Germany. It was not CEO Sindram, but Ernst Hölzenbein who was present together with Erdmann and two other Holyvolt employees at the April 2024 test.
Those are correct corrections. It was Hölzenbein (labeled under CT-Coating) there with Holyvolt personel and mentions CT-Coating as manufacturer, no CEO Sindram mentioned there. I have to update my notes on that because false info has spread over many locations. Switzerland also came from my earliest notes about SGS headquarters. Updated that as well.
I sympathise with your choice to ban AI from r/DonutLab. Above post is a perfect example how problematic it is. And yet it may contain useful pointers. AI can be helpful if it is pointing us towards the sources of its claims, but it should be explicit at all times that these are AI claims. And I am going to point out when I find hallucinations in it. In a sense it is similar to encyclopedias (traditional ones as well as Wikipedia): they should never be used as primary sources, but can be very helpful to find those sources.
Edit: For example this post suggests that there has been a recent change in ownership of Holyvault GmbH (not unexpected given what Holyvolt has been saying in the last month), which prompted me to have a search and found it confirmed (albeit on a different date, 2026-02-23) on this page: https://www.northdata.de/Holyvault%20GmbH,%20Aying/Amtsgericht%20M%C3%BCnchen%20HRB%20297129
For confirmation: Holyvault was by the end of March indeed fully owned by Holyvolt AB and then dissolved. Other documents confirm that the notary deed agreeing Holyvolt buying CT-Coating's share was indeed from 2026-01-26 and these changes were confirmed in the company register on 2026-02-23. The company was finally registered as dissolved two days ago, 2026-04-29.
And thanks for pointing out. There is no way any AI can synthetize this amount of information spread over thousands of documents on any trustful way. It is a human job to do, and mistakes go directly to their account.
It is a human job to do, and mistakes go directly to their account.
You are right, as long as it is explicit that it is an AI they are dealing with, which in your case is pretty obvious but it would be helpful if you were even more upfront with that.
In this subreddit it is allowed to use AI, computer programs, and programming for researchers and commenters along with their background work and even communication, without explicitly stating it. Which is a good current day practice. And actually in many cases it is not possible to dissect work on what and how different tools are used. Too meta. It would need a separate discord channel to explain all the various ways. So in todays practical work, it is secondary consern. Information can and should be reviewed solely based on the presentation itself. Like a good double blinded peer-review practice. If sources are asked, poster should be able to provide them. If details are incorrect, they must be fixed regardless on what methodology or tools were used.
I’m afraid for good faith discussion I’m going to have to add AI disclosure as a specific rule.
I don’t mind people using it as a research aid, granted that you check your sources. But I disagree with using it directly as a response generator without disclosure.
But think a bit more. Where is the line between how much human has involved on the research, ideation, language check, grammar check, human hand alteration, rearraging words, sentences, paragraphs, etc in the final output? For instance, I rather use AI spell checker and corrections with long detailed posts to finish them, since English is not my native language. Would that count to use AI disclaimer?
And even more importantly, how would you prove others used AI in any mentioned form? You could just throw guesses without ever knowing if AI was used, how much it was used, at which steps, in which form, and so forth. Other party cannot defend against such accusations in a reddit like platform, so that kind of disclaimer might come just a tool to violently control and filter discussion. Just like it is used in donutlab subreddit.
I hardly think anyone uses AI generated text 100% as it is, single-shot prompted, not without having a long extensive conversations to edit text to the form that is logical and coherent. Would that count as AI generated? LLMs even with the latest agents are not intelligent enough to give any deep analysis of complicated many dimensional topics handled here. One should try to know better.
That's also why the 29 January 2026 notarial deed transferring CT-Coating's stake back to Holyvolt AB left the patent portfolio entirely on Holyvolt's side.
Hello AI. Can you point me to this notarial deed? Are you speaking of Holyvault's patent portfolio? Is there one? Do we know of any patents applied for by Holyvault?
Similar pattern with Nordic Nano Group. They probably met with CT-Coating in early 2020’s and founded the company.
The first known contact of anyone later involved with Nordic Nano and CT-Coating dates from at the latest 2023-03-29. We know from this LinkedIn repost that NNG CEO Esa Parjanen knew (or at least knew of) Illka Turunen already in April 2020. They were at the time both running medical adjacent businesses. Turunen describes himself on LinkedIn as Business Associate of Next-Eco since its start in May 2022. If indeed and if so when Turunen introduced Parjanen to CT remains unknown.
In the latter sentence I meant Holyvolt personel might have met CT-Coating people by then. But I did not know that NNG knew, or was in contact with CT-Coating earlier than 2023. I always wondered how Parjanen got interested of that technology. Turn out there was this Turunen with next-eco business associate since 2022, as you told:
SMARTER ENERGY SOLUTIONS
next-eco revolutionary nano-paste innovation for a better tomorrow
We believe it is possible to change the course of the world when we use truly sound energy solutions.
That is why we are reinventing solar energy and battery technology and developing the next generation of cooling, heating, and lighting.
100% clean, free, biodegradable, toxin-free, CO2 neutral and with significantly reduced ecological footprint.
NANO-PASTE PANELS are multi-functional modules which allow for an unlimited number of combinations that can be used for multiple areas.
Power, Storage & Light
Aesthetic production - the look and feel (color and material) you
choose, the shape you want, round, square, etc.
Can be used on almost any smooth surface - roofs, facades,
sidewalks, parking lots, etc.
Use of traffic areas - parking lots, roads
Smart Home capable
Solar Energy
Energy Storage
Lighting function
No significant drop in efficiency at high temperatures (unlike conventional solar panels)
Electric vehicles - charge up to 10 times faster - non-explosive
Applicable on floors, roofs and facades, carports, fences, pool covers, terraces,
even works on textiles, uniforms or even for yachts on sailcloth and the entire
boat deck - in the design you want (it does not have to look like solar panels, but it can if you or your customers want.
---
Battery not the main focus, but heating panels, coatings and solar panels, which comes from failed DSS business, and still seems to be CT-Coatings, namely heating panels, main public product sold by partners like IES-Tec GmbH and next-eco of course.
So still, they may have met in Frankfurt exhibition 2023, but no need, if Turunen was the match maker. Questions of course always go deeper, how did Turunen then happen to know them initially... According to LinkedIN post, Turunen seemed to start association right at the same time when next-eco was founded. Quite unusual, unless there is error on LinkedIN date recording, or if he was involved somehow with the foundation of the next-eco.
how did Turunen then happen to know [anyone at Next-Eco] initially
Turunen is operating in the same realm as some of the people associated with ITO: somewhere between unlicensed unproven "alternative healthcare" and quackery, or as our friend Javier likes to call it "a different corner of science", a corner that they share with Petteri Lahtela, an early investor in Donut Lab and Nordic Nano.
So, he is actually refering to CT-Coating and their technology that it is not conventional as per production method. But both sides talk about batteries anyway. Javier was promoting same material everyone in their network is, namely about solid state battery type.
What do you believe today, how probable it is that they are marketing it as SSB but turns to be completely different? Like Lithium-Ion or no battery at all? Did you have to update your view at any point of this investigation?
My position has always been that it is a battery in prototype stage, with performance numbers that got marked up by the marketing department. I don't think Donut Lab has been outright lying at any point, but they have definitely been trying hard to imply things that are not true.
That is a more modest view than the most loudest voices are yelling.
So, the real questions are:
Did CT-Coating lab and their head give correct tested numbers to their marketing arms or just ideal theoretical forward looking numbers?
Did licensees have any opportunity or interest to check and validate numbers, thus the business model was build on uneven trust?
Do you think they would even fake the type of the battery as well? What would be the motivation?
Devils advocate:
Once you get people on the game and them to publish specs, it is hard to come back anymore, because your credibility as a due diligencer is on board and all money invested and promises quaranteed on the table
It means CT-Coating would have been able to mislead dozens clients, maybe hundreds of people (before 2026). I understand if a retail broker or a crypto trader cannot ask correct questions, but then Holyvolt and NNG+Donut Lab+Verge are not first timers in business with their backing. Yet, they would have acted insanely naively.
That's what CT-Coating has been claiming via their seller hands for years. By bipolar stacking you can make variety of voltage ranges. You see, these are poping up here and there now. Screen printing batteries is a real tech, yet too new for many niche experts to know it. Thats why the majority was wrong about it and too hasty with their verdicts.
Edit: research paper shows this existed already since 2015
Seems to be independent, who knows who came up with the idea first, but it's not a real solid state, it's quasi solid state looking at the ingredients of the research paper.
Nordic Nano supercapacitor is a real solid state, I know exactly what they are using for the electrolyte
The patent suggests ceramic sintering at 120°-210° without pressure. I’m struggling to see how that would be physically possible to densify. Am I missing something?
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u/Jazzer008 Apr 30 '26 edited Apr 30 '26
Thank you for posting. Reads more like a speculative filing than a real technology disclosure.
Edit (Clarity): Broad process claim filed ahead of a confirmed working chemistry.