H3X Technologies
YC W21Denver, US · Founded 2020 · Delaware corporation · 58 employees · 8 known investors
H3X designs and manufactures advanced electric motors for industrial applications. The company operates a full-stack engineering facility with in-house manufacturing capabilities including CNC machining, power electronics labs, and test cells.
Also known as H3X · H3X Technologies Inc.
Founders & leadership· Y Combinator alumni (W21)
H3X Technologies was founded in 2020 by Eric Maciolek, Jason Sylvestre, and Max Liben.
Board
Investors · 8
.jpeg){kind=logo}
Reported raises · per SEC filings
Form D private placements$29.4M disclosed across 4 rounds · 2021–2024
▶$20.3MraisedAug 2024 · 25 investors · Other TechnologyRule 506(b)
- Eric MaciolekExecutive Officer, Director
- Jason SylvestreExecutive Officer, Director
- Max LibenExecutive Officer
- Nathan DoctorDirector
- Offering amount
- $20.3M
- Amount sold
- $20.3M
- First sale
- Mar 2024
- Incorporated
- Corporation, Delaware, 2020
- Federal exemptions
- 06b
▶$3MraisedMar 2023 · 1 investors · Other TechnologyRule 506(b)
- Jason SylvestreExecutive Officer, Director
- Eric MaciolekExecutive Officer, Director
- Max LibenDirector
- Offering amount
- $3M
- Amount sold
- $3M
- First sale
- Feb 2023
- Incorporated
- Corporation, Delaware, 2020
- Federal exemptions
- 06b
▶$1.8MraisedJun 2022 · 2 investors · Other TechnologyRule 506(b)
- Max LibenDirector
- Jason SylvestreExecutive Officer, Director
- Eric MaciolekExecutive Officer, Director
- Offering amount
- $2M
- Amount sold
- $1.8M
- First sale
- Jun 2022
- Incorporated
- Corporation, Delaware, 2020
- Federal exemptions
- 06b
▶$4.3MraisedJun 2022 · 44 investors · Other TechnologyRule 506(b)
- Jason SylvestreExecutive Officer, Director
- Max LibenDirector
- Eric MaciolekExecutive Officer, Director
- Offering amount
- $4.3M
- Amount sold
- $4.3M
- First sale
- Jan 2021
- Incorporated
- Corporation, Delaware, 2020
- Federal exemptions
- 06b
Source: SEC EDGAR Form D. Amounts as filed; amended filings shown once at their latest values.
Company profile
researched Aug 2026H3X Technologies is a US electric propulsion company that develops integrated motor drives (IMDs) — electric machines with integrated, co-optimized inverters — for weight-sensitive, volume-constrained and high-power applications. Its product line spans the HPDM-30, HPDM-90S, HPDM-180D, HPDM-350 and HPDM-500 motors plus the HPDG-30 diesel genset, with published specifications including a 33 kW / 4.1 kg unit at 20,000 RPM (HPDM-30), a 140 kW / 11 kg unit at 20,000 RPM (HPDM-140), a 180 kW unit at 2,985 RPM (HPDM-180R) and a 92 kW / 22 kg unit at 5,500 RPM (HPDM-90S). All products can operate as either motors or generators.
The company positions its core technology as scalable from 30 kW to 30 MW, with continuous power density stated up to 12 kW/kg. Target applications include electric and hybrid aircraft, eVTOL, airships, rocket actuators and pumps, space vehicles and more-electric aircraft systems; uncrewed aerial systems, hypersonic aircraft, undersea AUVs, submarines, specialized ground vehicles and mobile power generation; ferries, hybrid-electric ships, workboats, fast-supply vessels, waterjets, hydrofoiling craft and unmanned surface vessels; and mining vehicles, e-fracing, industrial heat pumps, applied HVAC and MW-class power generation. H3X states that it designs, develops and manufactures all of its products in the USA and frames this as a commitment to domestic manufacturing and engineering capability.
Business model
H3X sells hardware — integrated motor drives and gensets — to industrial and aerospace customers, supported by customer and supplier intake processes and published sales and supplier terms and conditions.
Latest developments
Recent company news includes a year-in-review post for 2025 (published January 2026), an announcement of a compact diesel genset for hybrid marine and industrial applications (February 2026), and third-party coverage of the HPDG-30 hybrid genset in Uncrewed Systems by Rory Jackson (April 2026).
▸Full profile — market position, technology, go-to-market, geography
Market position
H3X frames its products as the most power-dense integrated motor drives available, differentiating on continuous power density (up to 12 kW/kg), inverter integration within the motor package, scalability of a single core architecture across a wide power range, and domestic US design and manufacturing.
Technology
Integrated motor drive architecture in which the electric machine and inverter are co-optimized and packaged together. The company cites continuous power density up to 12 kW/kg, high-speed operation up to 20,000 RPM on some units, a product range of 30 kW to 1 MW+, and core technology scalable to 30 MW. All units are reversible, usable as either motors or generators.
Go-to-market
Original equipment manufacturers and operators in aerospace (electric/hybrid aircraft, eVTOL, space vehicles), defense (uncrewed aerial systems, submarines, AUVs, ground vehicles), marine (ferries, workboats, unmanned surface vessels) and heavy industry (mining, e-fracing, HVAC and heat pumps, MW-class power generation).
Geography
All design, development and manufacturing is stated to take place in the United States.
Compiled by commissioned research from 1 cited public sources — announcements, filings, and press listed under research sources below.
Key figures
latest reportedCompany-reported or press-reported figures, each dated to when it was claimed — not independently audited.
Competitors · 3
by search overlap
Companies competing with H3X Technologies for the same Google search keywords, organic and paid, via search-intersection analysis.
Non-dilutive funding · 2 SBIR/STTR awards
Federal grants — no equity taken| Agency | Phase | Year | Amount |
|---|---|---|---|
| NASA | Phase II | 2023 | $849.6K |
| NASA | Phase I | 2023 | $149.9K |
Source: SBIR.gov award data (U.S. Small Business Administration). SBIR/STTR awards are competitive federal R&D grants and contracts — non-dilutive capital alongside any venture rounds above.
Timeline · 2
launches, deals, and filingsTrade publication Uncrewed Systems published an article by Rory Jackson on the H3X HPDG-30 hybrid genset.
H3X announced a compact diesel genset targeting hybrid marine and industrial applications.
Dated company events from announcements, filings, and press; legal rows summarize public dockets and regulator releases.
Legal entities · 1
corporate structureIn the news
▸Research sources · 1
primary sources listed
- H3X Technologiesh3x.tech · web
1 public sources were cited for this profile; the first-party ones are listed here.
Frequently asked questions
- What does H3X Technologies do?
- H3X Technologies designs and manufactures power-dense integrated motor drives from 30 kW to 1 MW+ for aerospace, defense, marine and heavy industry.
- Who founded H3X Technologies?
- H3X Technologies was founded by Eric Maciolek, Jason Sylvestre, Max Liben in 2020.
- Who are H3X Technologies's investors?
- H3X Technologies's investors include Industrious Ventures, Metaplanet, Origin Ventures, Y Combinator, Cubit Capital, Lockheed Martin Ventures, Lombardstreet Ventures, Soma Capital.
- How much funding has H3X Technologies raised?
- H3X Technologies has disclosed $29.4M raised across 4 rounds.
- Where is H3X Technologies headquartered?
- H3X Technologies is headquartered in Denver, US.