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Stellantis Company Overview | Solid-State Batteries

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COMPANY PROFILE / Solid-State Battery

Stellantis
— Continuously acquiring joint ventures in liquid batteries while only the full-solid-state battery is advancing ahead

The mention of Stellantis with full-solid-state batteries is due to 2021 in the United StatesFactorialhe75 million dollarsto invest, and in June 2026began road tests with solid-state battery cells mounted on the development vehicle of the Dodge Charger Daytonafrom. On the other hand, the company withdrew from its partnership with LG Energy Solution in 2025 to exit the European battery joint ventureACCWe are fully impairing the investment. Folding back the liquid system while leaving only solid-state batteriesThis is a rare composition in this field. In this article, the scale of the automotive industry is kept to a minimum.what is being invested in all-solid-state batteries, who is collaborating with whom, and what are the goals?focuses on.

Composition: Uses primary information from Stellantis’ Form 20-F submitted to the U.S. SEC in December of the 2025 fiscal year (filed on February 26, 2026), the company’s official press releases, and the documents filed by Factorial Energy with the U.S. SEC as primary information / Last updated September 2026

The things you will learn in this article
  1. Understand Stellantis in 30 seconds and its position in solid-state batteries
  2. About the logo and company name
  3. Where is this company in the world of solid-state batteries
  4. Company size (automotive industry is concise)
  5. Resources invested in solid-state batteries
  6. Previous efforts
  7. Future plans
  8. What is this company aiming for with solid-state batteries?
  9. Mapping of collaborations in the field of all-solid-state batteries
  10. Techniques and methods adopted
  11. Risks faced by this company
  12. Glossary / References / Claims and Corresponding References Table

1. Understanding Stellantis in 30 seconds and its position with solid-state batteries

Official NameStellantis N.V.In 2021, FCA and PSA merged to form
Headquartersthe
Amsterdam
registered office as described in the 20-F filing
ListedNYSE: STLA
Milan/Paris
Euronext Milan STLAM/Paris STLAP
classification in this fieldAutomotive manufacturers
(investment-type)
Cells are not made in-house
Investment recipientFactorial
(Nasdaq: FAC)
$75 million in 2021
verified cell performance375Wh/kg
77Ah
both companies announced in April 2025
Proof-of-concept vehicleDodge Charger
Daytona
Start of public road testing in June 2026
Reference to 20-FNoneThere is no mention of all-solid-state batteries in the mandatory disclosure
One point to grasp first

Companies working on solid-state batteriesAutomotive manufacturers, battery manufacturers, and startupsare divided into three types. Stellantis is one of themAutomotive manufacturersand does not create cellsacquires through investment and joint developmenttype fact. What sets us apart from other companies is,is in the process of reducing its overall investment in batteriesIt is. In 2025, the company decided to withdraw from its joint venture with LG Energy Solution in North America and invest in a battery joint venture in Europe.NextStar Energyfrom the withdrawal decision, investment in the European battery joint ventureACCof the full amount of write-downs, and also discontinued its hydrogen fuel cell business. Among these,solid-state batteries are still not stopped.. However, the mandatory disclosure for the fiscal year ending December 2025 in Form 20-F does not mention either ‘all-solid-state battery’ or ‘Factorial’. This drop is the most important clue when reading Stellantis.

2. Regarding logo and company name display

Note on notation: A holding company Stellantis N.V.(Dutch entity) and has an investment in Factorial.Stellantis Europe S.p.A.(formerly FCA Italy S.p.A., Turin, Italy) Stellantis Ventures B.V. two subsidiaries. Additionally, the development vehicle equipped with a solid-state battery isDodgea brand’s car, and Stellantis is Abarth・Alfa Romeo・Chrysler・Citroën・Dodge・DS・FIAT・Jeep・Lancia・Maserati・Opel・Peugeot・Ram・Vauxhall, etc. Holdings that bundle many brandsIn this article, we will distinguish between company names and brand names where necessary.

Official website:https://www.stellantis.com/en/news/press-releases/2024/october/stellantis-and-factorial-take-next-step-to-accelerate-the-future-of-electric-vehicles-with-solid-state-battery-technology

3. Among the world of all-solid-state batteries, where is this company located?

Companies that are working on solid-state batteries Even though the companies are ‘working on solid-state batteries’, their positions and goals are completely different Automotive manufacturers battery manufacturer Startups Creating batteries for their own cars Creating batteries to sell Proving technology and raising capital Stellantis/VW BMW/Mercedes/Toyota and others CATL/Samsung SDI LG Energy Solution/SK On Factorial/QuantumScape Solid Power/ProLogium and others Have your own exit for mass production Can supply to multiple customers Do not have mass production equipment on your own Even if it fails, cars can be sold Cannot sell unless adopted Funding runs out and it ends Stellantis is on the left, but it is separating both joint ventures of liquid battery systems in 2025. It is narrowing its foothold as a battery maker in the middle and is only retaining the investment in the startup on the right.
Figure 1 The three types of companies working on all-solid-state batteries and Stellantis’s positioning. The classification is based on this article, and examples are drawn from 23 companies featured in this series. Calculations in this articleThe decision to withdraw from NextStar Energy in 2025 and ACC’s full impairment are based on the company’s 20-F filing for the fiscal year ending December 2025.

4. Company Size (Automotive Business is Briefly Covered)

The automotive business itself is not the main topic of this article, so we will only focus on its size. fact. All values are cited from the Form 20-F for the fiscal year ending December 2025.

Indicator (in millions of euros)Fiscal year ending December 2024Fiscal Year Ending December 2025
Operating income156,878153,508
Research and Development Expenses5,78411,145
Operating Profit/Loss (△ indicates loss)3,687△26,254
Net Profit for the Period (△ indicates loss)5,520△22,332
ItemContent
Units Shipped5,415 thousand units (2024) 5,484 thousand units(as of 2025)
average number of employees259,118 people (as of 2024) 253,654 people(as of 2025)
HeadquartersAmsterdam, Netherlands (Stellantis N.V.)
listed marketNew York (NYSE: STLA), Euronext Milan (STLAM), Euronext Paris (STLAP)
Please note

The number above isfor the entire company.It does not represent the scale of business for solid-state batteries. Not to mention, the ‘All-solid-state battery’ and ‘Factorial’ are not mentioned even once in the Form 20-F for the fiscal year ending December 2025. fact。 Research and development expenses increased from approximately 5.7 billion euros to nearly 11.1 billion euros by 2025, but according to the company’s explanation, the main reason isthe write-off of development costs due to the revision of product plans or project cancellationsand it was not because the investment in solid-state batteries increased Unconfirmed / Future. This company has no legal disclosurepress releases and the SEC filings of its investment partner, Factorialto read.

5. Resources invested in solid-state batteries

Stellantis publicly disclosed the amount isonlyone. The investment in Factorial in 2021 was $75 million. The other numbers are related to the listing of the company in the United States in 2026.Factorial-side disclosurecan be obtained. In this article, we will always specify which disclosure it is referring to.

Resource typesThe content that has been made public.Classification
Investment abroad (amount and timing)Invested $75 million in Factorial in 2021.Stellantis itself has recorded this amount in both press releases in October 2024 and April 2025.fact
external investment (equity stake)At the time of Factorial’s U.S. IPO,Stellantis Europe S.p.A. held 8,234,493 shares, and Stellantis Ventures B.V. held 435,502 sharesand total8,669,995 sharesheld. Series A common stock of9.5%and all shares8.1%equivalentFact (Disclosure of Investment Holdings)
external investment (additional loans)in the convertible bonds due in August 2025Stellantis Ventures B.V. for $2 millionto be assumed (full balance as of December 31, 2025). The same amount is also being assumed by Mercedes-Benz’s investment subsidiary.Fact (Disclosure of Investment Holdings)
Investment in external entities (governance)Stellantis-related individualshave been appointed as a director of Factorial. Among the directors before the company went public were Michael Bly, who was employed by Stellantis Europe’s related companies, and Jon K. Nelson, CEO of Stellantis Financial Services, among othersFact (Disclosure of Investment Holdings)
joint development agreementThe joint development agreement dated August 1, 2025replaced the contract dated November 20, 2021. It defines technical goals, milestones, and deliverables, and divides the development activitiesFact (Disclosure of Investment Holdings)
among its own design assetsAll-solid-state cells to be incorporated into existing battery packsStellantis has designed a new patented mechanical structure. The control system and pack design were also replacedfact
person (full-time staff)number of full-time staff for solid-state batteriesNot disclosed
money (investment amount)Development costs and equipment investment for all-solid-state batteries excluding equity investmentsNot disclosed
Collaboration with universities and research institutionsThe university joint research on solid-state batteries could not be confirmed in the company’s official documentsUnconfirmed
Material engineer’s perspective: ‘The significance of being included in an existing package’

The most technically significant announcement for June 2026 is combining FEST cells with existing battery packs using a new mechanical structure.This description says. fact. When installing solid-state batteries in vehicles, it is usuallydesigned from scratchIt becomes necessary. Since the cells change in thickness due to charging and discharging, a mechanism that can be pressed from the outside is required, and this mechanism does not fit into the gaps of the existing packs.

Stellantis says thatpatented a mechanismto solve the problem Calculations in this article. In response to Mercedes’ air pressure actuator and BMW’s control of operating pressure, Stellantis has put forward a mechanical structure answer.mechanical structureIt becomes necessary. Stellantis has emphasized that ‘FEST has high compatibility with the manufacturing process of liquid lithium-ion batteries, and this is an important path to scale up.’ This is also in the same line of thinking. I want to make and publish the method without significantly changing what we already haveThis consistent stance can be read. The reason why companies that are cutting back on investments in batteries are continuing with only solid-state batteries is likely due to this.

6. Previous Efforts

periodincidentMeaning
2021 yearInvested 75 million dollars in Factorial.On November 20th of the same year, a joint development agreement was concludedThe only number Stellantis publicly disclosed regarding the amount
October 23, 2024Announced the demonstration fleet plan using vehicles based on the STLA Large platform.The first is Dodge Charger Daytona. It will be on public roads by 2026. FEST’s energy density exceeds 390Wh/kg as explainedSTLA Large is said to be designed to support up to 2 million vehicles worldwide
April 24, 2025Successfully announced the verification of FEST cells in vehicle size.77Ah cell for375Wh/kg, over 600 cycles,charging from 15% to 90% in 18 minutes、−30℃〜45℃maximum4Cdischargecell-specific values were first made public
2025 yeardemonstration fleetfabricate the first one(Disclosure on the side of Factorial)preliminary stage of public road testing
2025 yearMeanwhile, battery joint venture with LG Energy Solutiondecision to withdraw from NextStar Energy(1.6 billion euros in costs). Battery joint venture in Europefull write-down of investment in ACC(500 million euros). The hydrogen fuel cell business will also be cutWithdrawing from in-house production of liquid systems
August 1, 2025A joint development agreement with FactorialTo renegotiateReplacing the contract signed in November 2021Revised the technical goals and milestones
June 11, 2026Dodge Charger Daytona development car equipped with FEST cells and started road testing.First full-solid-state battery installation in Stellantis vehicles. It is the first integrated vehicle in North America.Patented mechanical structure incorporated into existing packs.

7. Future Plans

Current stageRoad testing and
Calibration
Verification of pack performance, reliability, and safety
Proof-of-concept fleetmulti-stage
development vehicle program
The first car in June 2026 will be
platformSTLA LargeJeep・Dodge・Chrysler・Alfa Romeo・Maserati
production timingNot announcedmass-produced vehicles and factories are also not disclosed

The company is conducting a program of public road tests and calibration. to further verify the pack performance and reliability during charging and driving times, as well as vehicle safety.and states fact. This is not the next stage of the demonstration fleet.but rather the first unit of the demonstration fleet itself..

things that could not be confirmed

Next, all of the following are not recorded in official documents Unconfirmed / Future。

solid-state batteryProduction Start Year/mass-produced vehicle/factory that makes cells/ number of demonstration fleet/pack capacity (kWh) and vehicle range/ Whether additional funding has been provided for the factorial/Development costs and number of dedicated personnel for solid-state batteries. The target announced in October 2024, ‘By 2026 on public roads’, was met by the start of road testing with one development vehicle in June 2026, but No information has been publicly disclosed regarding the fleet size. The production timing and quantity based on reports will not be adopted in this article.

8. What does this company aim to achieve with solid-state batteries?

This part includes information that the company has not directly stated.Inferred from primary sources within the scope of what can be read.Along with the basis, I will write it down.

What can be readprimary informationClassification
The intention to make cells in-houseno longer existsRetired from the joint venture with LG by 2025 and fully impaired the investment in ACC. On the other hand, the investment in Factorial is maintained.speculation
The aim isPerformance is not what we are focusing on; instead, cost and lightnessWhat is repeatedly mentioned in the announcement is ‘lightweight, efficient, and reducing customer costs’. The specific range of flight distance is not shownspeculation
We do not want to change the current method‘FEST has a high compatibility with the manufacturing process of liquid lithium-ion batteries, which is an important path for scaling up’, as the CTO explicitly statedfact
The first application will behigh-performance vehicleThe chosen ones are the Dodge Charger Daytona and STLA Large. The company explains that this platform is for ‘large-scale production EV SUVs and high-performance vehicles’speculation
They believe that their added value lies in the pack designThey design the mechanical structure themselvesThey have obtained patentsThe cells themselves are made by Factorialspeculation
Investorshave not yet been sold toThere is no mention of full-solid-state batteries or Factorial in the Form 20-F for the fiscal year ending December 2025fact
The basis for speculation is only one

The heaviest point of this article isthe fact that full-solid-state batteries do not appear in the Form 20-Fat all fact. Form 20-F is a legal filing document submitted to the U.S. Securities and Exchange Commission, and it carries legal responsibility for its content. That’s why each company iswriting down the initiatives they consider important for investment judgment here. Toyota has explicitly stated its target for commercializing solid-state batteries by 20-F, and Honda also mentioned one of the next-generation batteries.

Stellantis is not doing this because it can’t talk about the results of this endeavor in the context of performance. It seems that it’s still not in a position to discuss the results.This is what can be read. Unconfirmed / Future. The same 20-F document, which devotes several pages to the joint venture of liquid battery systems, is combined with the fact that solid-state batteries are‘not at the stage of ‘money talk’ but rather ‘technology talk’.This arrangement is as follows. The press release is the communication from the technology department, and the 20-F document is the communication from the finance department. The distance between these two represents the current positioning of Stellantis in solid-state batteries.

9. Mapping of solid-state battery collaborations

Stellantis-led battery field relationships. Only the relationships recorded in the official announcement, Form 20-F, and SEC filings by Factorial. Relationships based on press reports are not included. Stell Tis Factorial Energy (Startup) Nasdaq: FAC Lithium Metal Investment 75 million dollars, Shareholding 8.1% Dodge Charger Daytona (Group Internal) STLA Large Platform Start of public road testing in June 2026 ACC (Joint Venture – Liquid System) Automotive Cells Company Write-off in full by 2025 NextStar Energy (joint venture, liquid-based) with LG Energy Solution and Decision to withdraw by 2025 Investment: $75 million in Factorial in 2021 Participation: 8.1% (as of 2026, based on SEC filings from Factorial) Joint development of solid-state batteries (solid line) Group within (solid line) JV in liquid battery (solid line)
Figure 2 Stellantis-led battery field relationship. Factorial is connected.Investment (dotted line) and joint development (solid line) are bothThe orange two arejoint venture in liquid lithium-ion batteriesand not solid-state batteries. Source: Stellantis official press releases (October 23, 2024, April 24, 2025, June 11, 2026), 2025 fiscal year Form 20-F, and SEC filings of Factorial Energy.8.1% stake is disclosed by the Factorial sideAnd, Stellantis itself has not disclosed the stake ratio.

10. Technology Approach Used

ItemThe content that has been made public.
Cell supplierUnited StatesFactorial(Massachusetts). The technology isFEST®(Factorial Electrolyte System Technology)
Negative electrodeLithium metal. FEST is explained by Factorial to be replaceable with lithium metal instead of graphite anode.
ElectrolyteSolid electrolyte. No indication whether it is a sulfide system or an oxide system.High compatibility with the manufacturing process of liquid lithium-ion batteries.stressed by Stellantis’ CTO
a validated cell77Ah, energy density375Wh/kg、600 cycles over(announced by both companies in April 2025)
chargingat room temperaturefrom 15% to over 90% in 18 minutes
operating temperature and output−30℃〜45℃during operation. Discharge rate is maximum4C
method of packaging into the packStellantis designed a patent-protected mechanical structureand integrated all-solid cells into existing battery packs. The control system and pack design were also adapted to meet automotive requirements
Explanation as of 2024FEST’s energy density isover 390Wh/kgIt was stated. The verification value in 2025 was 375Wh/kg, which is lower than this
Material engineer’s perspective: Reading the numbers from 390 to 375

Announcement in October 2024‘Over 390Wh/kg’In the verification results of April 2025,「375Wh/kg」 fact. The decrease in numbers is not a retreat, but rather…The thing being measured has changedand it reads naturally Calculations in this article. The former is the value expressed as Factorial’s technical potential, and the latter is A cell with a size of 77Ah, which meets the requirements for over 600 cycles of life, 18-minute fast charging, and operation at -30℃It is.

In battery development, increasing energy density is relatively easy. By thickening the cathode, thinning the electrolyte, and applying high pressure, the numbers will improve. However, doing so will reduce the lifespan, make fast charging impossible, and prevent operation at low temperatures. The CEO of Factorial himself says ‘Battery development is a compromise technology,’Optimizing a single metric is simple, but achieving high energy density, long lifespan, fast charging, and safety in a vehicle-mounted size is the breakthrough.‘This is precisely the point they are making. When comparing cell numbers in this series, ‘the value that satisfies multiple conditions simultaneously’Please always confirm it.

11. The risks this company faces

RisksContentClassification
The company as a whole is operating at a lossFor the fiscal year ending December 2025, operating losses are 26.25 billion euros and net losses for the period are 22.33 billion euros. Investment judgments regarding long-term themes will become stricterfact
Reorganization of battery-related operations is underwayIn the same year of 2025, withdrawal from NextStar Energy (1.6 billion euros), full impairment of ACC (0.5 billion euros), and also cancellation of hydrogen fuel cell projectsfact
not recorded in the mandatory disclosureNo mention of full-solid-state batteries or Factorial in Form 20-F, and it is not positioned as an important matter for investorsfact
does not have means to make cellsits own battery production is shrinking, and it is not clear where mass production will be entrustedspeculation
the investment partner is non-exclusive and collaborates with other companiesFactorial is developing a joint venture agreement with Mercedes-Benz, Hyundai Motor, and Kia. Mercedes-Benz is also a 8.1% shareholder of Factorial.fact
The invested company has just gone public.Factorial has just gone public in the United States through a SPAC in 2026 and does not have mass production experience.speculation
The scale of the demonstration is unknown.Only the start of road testing for one development vehicle has been announced. The number of vehicles in the fleet and cumulative mileage are not disclosed.Unconfirmed / Future

12. Glossary

All-solid-state battery
A battery that uses a solid electrolyte instead of a liquid. This allows for the use of new anode materials.
FEST
Factorial Electrolyte System Technology. The name for Factorial’s solid electrolyte technology.
Ah (ampere moment)
The amount of electricity stored in a cell. For vehicle use, it is generally considered that 40Ah or more is the standard.
Wh/kg
Energy per kilogram. Lithium-ion batteries in production are generally around 250 to 330 Wh/kg.
4C discharge
It can pass four times the capacity current. It is a guideline for output that can be used up in 15 minutes.
STLA Large
Stellantis’ large vehicle common platform. Jeep, Dodge, Maserati, etc., use it.
ACC
Automotive Cells Company. A European battery joint venture in which Stellantis and others invest. Liquid system.
Form 20-F
An annual report submitted by a foreign company listed in the United States to the U.S. Securities and Exchange Commission. It is audited and carries legal responsibility.
Conceptual illustration: The idea of replacing only the mechanical structure while keeping the frame of the existing battery pack to accommodate solid-state cells.AI-generated conceptual diagram
Figure 3 Conceptual illustration of Stellantis’ approach to solid-state batteries (AI-generated conceptual illustration. It is not a photograph of actual equipment or products).

13. Source

  1. Stellantis N.V. Form 20-F for the fiscal year ended December 31, 2025(filed with the U.S. SEC on February 26, 2026)。Net income, research and development expenses, operating profit, net income for the period, shipment volume, average number of employees, headquarters location, listing market, withdrawal from NextStar Energy and full impairment of ACC, termination of hydrogen fuel cell business.Used to confirm the absence of mention of all-solid-state batteries and Factorial. https://www.sec.gov/Archives/edgar/data/1605484/000160548426000021/stellantis-20251231.htm
  2. Stellantis Press release ‘Stellantis and Factorial Take Next Step to Accelerate the Future of Electric Vehicles with Solid-State Battery Technology’ (October 23, 2024)。$75 million investment in 2021, demonstration fleet using Dodge Charger Daytona, selection reasons for STLA Large, over 390 Wh/kg. https://www.stellantis.com/en/news/press-releases/2024/october/stellantis-and-factorial-take-next-step-to-accelerate-the-future-of-electric-vehicles-with-solid-state-battery-technology
  3. Stellantis Press release ‘Stellantis and Factorial Energy Reach Key Milestone in Solid-State Battery Development’ (April 24, 2025)。77 Ah cell, 375 Wh/kg, over 600 cycles, 15% to 90% charge in 18 minutes, -30°C to 45°C, 4C discharge, joint optimization of pack design. https://www.stellantis.com/en/news/press-releases/2025/april/stellantis-and-factorial-energy-reach-key-milestone-in-solid-state-battery-development
  4. Stellantis Press release ‘Stellantis and Factorial Integrate Advanced Solid-State Battery into Stellantis Development Vehicle and Launch Road Testing’ (June 11, 2026)。Installation on the Dodge Charger Daytona development vehicle, start of road testing, patented mechanical structure, CTO’s statement, list of Factorial investors. https://media.stellantisnorthamerica.com/newsrelease.do?id=27822
  5. Factorial Energy Inc. Form 424B3 (filed with the U.S. SEC on September 21, 2026)。Number and ownership percentage of Stellantis Europe S.p.A. and Stellantis Ventures B.V. shares, joint development agreement dated August 1, 2025, $2 million convertible bonds in August 2025, relationship with directors, FEST’s technology content, performance of the 77 Ah cell, production timing for the first demonstration fleet. https://www.sec.gov/Archives/edgar/data/2049662/000110465926109360/tm2618963d3_424b3.htm

14. Table of Correspondence between Claims and Sources

Main Argument in the BodyClassificationSources
Pure Profit · Research and Development Expenses · Operating Income · Net Income for the Current Period (2024, December 2025 period)factSource 1 https://www.sec.gov/Archives/edgar/data/1605484/000160548426000021/stellantis-20251231.htm
Shipment Volume of 5,484 Thousand Units · Average Number of Employees 253,654 · Headquarters in Amsterdam · Listed MarketfactSource 1 https://www.sec.gov/Archives/edgar/data/1605484/000160548426000021/stellantis-20251231.htm
Withdrawal from NextStar Energy (€1.6 billion), full impairment of ACC (€500 million), and termination of hydrogen fuel cell businessfactSource 1 https://www.sec.gov/Archives/edgar/data/1605484/000160548426000021/stellantis-20251231.htm
Increase in research and development expenses in 2025 leading to a review of product plans and project cancellationfactSource 1 https://www.sec.gov/Archives/edgar/data/1605484/000160548426000021/stellantis-20251231.htm
The mention of solid-state batteries or Factorial is absent in Form 20-F.factSearch the full text of Reference 1 and verify https://www.sec.gov/Archives/edgar/data/1605484/000160548426000021/stellantis-20251231.htm
$75 million investment in Factorial in 2021factSource 2, 3 https://www.stellantis.com/en/news/press-releases/2024/october/stellantis-and-factorial-take-next-step-to-accelerate-the-future-of-electric-vehicles-with-solid-state-battery-technology
Demonstration fleet plan by Dodge Charger Daytona (October 2024) and selection rationale for STLA Large, including explanation of over 390Wh/kgfactSource 2 https://www.stellantis.com/en/news/press-releases/2024/october/stellantis-and-factorial-take-next-step-to-accelerate-the-future-of-electric-vehicles-with-solid-state-battery-technology
77Ah cell with 375Wh/kg, over 600 cycles, rapid charging in less than 18 minutes, operating temperature range of -30°C to 45°C, 4C dischargefactSource 3 https://www.stellantis.com/en/news/press-releases/2025/april/stellantis-and-factorial-energy-reach-key-milestone-in-solid-state-battery-development
Scheduled for installation on the development vehicle and start of road tests on June 11, 2026, patented mechanical structure, CTO’s statementfactSource 4 https://media.stellantisnorthamerica.com/newsrelease.do?id=27822
Mercedes-Benz, Hyundai Motor, and Kia are among the investors in FactorialfactSource 4 https://media.stellantisnorthamerica.com/newsrelease.do?id=27822
Number of shares held: 8,669,995 shares · Series A common stock at 9.5% · 8.1% of total sharesFact (Disclosure of Investment Holdings)Source 5 https://www.sec.gov/Archives/edgar/data/2049662/000110465926109360/tm2618963d3_424b3.htm
Joint development agreement dated August 1, 2025 (replacing the one dated November 20, 2021), convertible bonds worth $2 million, relationship with directors, production of the first demonstration fleetFact (Disclosure of Investment Holdings)Source 5 https://www.sec.gov/Archives/edgar/data/2049662/000110465926109360/tm2618963d3_424b3.htm
FEST is compatible with lithium metal, graphite, and silicon anodes, mass-produced lithium-ion batteries have a capacity of 250 to 330 Wh/kgFact (Disclosure of Investment Holdings)Source 5 https://www.sec.gov/Archives/edgar/data/2049662/000110465926109360/tm2618963d3_424b3.htm
Classification of three types of all-solid-state batteries (Automotive / Battery / Startup)Calculations in this articleArrangement by this article. Company names are exemplified from the 23 companies in this series
Development costs and dedicated personnel numbers for all-solid-state batteriesUnconfirmed / FutureNon-disclosed. This article does not estimate either.
Production start year, production vehicle model, factory that makes cells, number of demonstration fleet vehicles, pack capacity and rangeUnconfirmed / FutureNot recorded in references 1-5. Do not adopt reported values. https://media.stellantisnorthamerica.com/newsrelease.do?id=27822
FEST’s solid electrolyte is either sulfide-based or oxide-basedUnconfirmed / FutureNot explicitly stated in official documents. This article does not estimate https://www.sec.gov/Archives/edgar/data/2049662/000110465926109360/tm2618963d3_424b3.htm
Research collaboration with universities and research institutions on all-solid-state batteriesUnconfirmed / FutureUnable to confirm from official materials. This article does not state that it does not exist. https://www.stellantis.com/en/news/press-releases/2025/april/stellantis-and-factorial-energy-reach-key-milestone-in-solid-state-battery-development
The company no longer has the intention to make cells themselvesspeculationThe interpretation of this article based on the organization and maintenance of two liquid joint ventures and Factorial investment
The reading that the aim is not performance but cost and lightnessspeculationThe interpretation of this article based on repeated expressions in the presentation
The reading that the first application will be for high-performance vehiclesspeculationThe interpretation of this article from the selection of demonstration vehicles and platforms
The reading that we believe our company’s added value lies in the design of the packspeculationThe interpretation of this article from the fact that we design the mechanical structure ourselves and obtain patents
The reading that the change from 390Wh/kg to 375Wh/kg is due to ‘the difference in what is being measured’speculationThe explanation of this article regarding the trade-offs in battery development
Solid-state batteries are still not ‘the money talk’speculationInterpretation based on the absence of information in Form 20-F
Risk due to lack of means to make cells and the fact that the investment target has just gone publicspeculationInterpretation based on the structure of the partnership and the situation of the investment target

Last Updated: September 23, 2026 / Troy Technical
The numbers in this article are based solely on the legal filings submitted by Stellantis to the U.S. Securities and Exchange Commission (SEC), the company’s official press releases, and the legal filings submitted by Factorial Energy to the SEC. We have not used estimates or values from news reports. The ‘estimates’ noted in this article are interpretations drawn from primary information and do not reflect the company’s public statements.

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