PEM Electrolyzer Balance of Plant Patent Snapshot 2026
The PEM electrolyzer balance-of-plant patent space is highly concentrated, with Hoeller Electrolyzer GmbH alone holding 20 of 26 total patent families in scope. Activity peaked in 2018 and has since eased substantially, signaling a field that has passed its early innovation surge but where targeted adjacent branches remain thinly covered.
Hoeller Electrolyzer GmbH commands an overwhelming lead in a very small field
With 20 patent families, Hoeller Electrolyzer GmbH ranks first by a wide margin among all filers in this space. The next largest filer, Shanghai Weishen Electronic Technology Co., Ltd., holds just 2 patent families, and the remaining ranked applicants each hold 1.
The top five filers account for 96% of the combined total among the ranked applicants visible in this query, an extreme concentration ratio that leaves virtually no competitive buffer for second-tier entrants. The tier gap between the leader and all challengers is structural rather than cyclical.
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 1 | Hoeller Electrolyzer GmbH | 20 | |
| 2 | Shanghai Weishen Electronic Technology Co., Ltd. | 2 | |
| 3 | M S Sentient Engines Pte Ltd | 1 | |
| 4 | Massachusetts Institute of Technology | 1 | |
| 5 | Huadian Heavy Machinery Co., Ltd. | 1 | |
| 6 | Vellore Institute of Technology | 1 |
Hoeller Electrolyzer GmbH’s position implies proprietary depth in electrolytic production processes (C25B), covering cell design, operational methods, and compound production variants. Any entrant seeking to compete directly on core stack and ancillary system integration will face a dense thicket of existing filings from a single incumbent.
Filing counts for the most recent 18–24 months are subject to publication lag and will likely increase as applications are published; the apparent low activity in 2024–2025 should be interpreted cautiously. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Activity peaked in 2018 and has eased; C25B electrolytic production dominates the technology mix
Two charts together reveal both the temporal arc of innovation activity and the current distribution across technology branches. Reading them together clarifies where the field has concentrated effort and where coverage thins out.
Annual filing trend
Filings reached their high point in 2018 with 9 families filed that year, then pulled back sharply through 2020–2022, with zero recorded filings in both years. A modest uptick appears in 2025 (3 families), but given publication lag this should not yet be read as a confirmed recovery. The overall multi-year trajectory confirms the field is in decline from its 2018 peak.
↗ Hover for values · click a bar to ask EurekaTechnology composition
C25B (electrolytic production of compounds) accounts for all 26 records and is overwhelmingly the visible branch, reflecting the core electrolyzer stack and operating-method focus of the corpus. Secondary branches — C02F (water and wastewater treatment), C01B (non-metallic elements and inorganic compounds), B60K (vehicle propulsion), and F02M (fuel supply) — each appear in only 1–4 records, pointing to thin coverage of downstream hydrogen applications and system integration sub-systems.
↗ Hover for values · click a bar to ask EurekaHighly cited patent families surfaced by the query
Citation-heavy patent families returned by the query. Use this section as citation context, not as a curated list of the most topic-specific patents.
Method for operating a water electrolysis device
A method for operating a water electrolysis device produces hydrogen and oxygen from water. In the electrolysis device, water which comes from a PEM electrolyzer (<b>1</b>) is fed to a first heat exchanger (<b>10</b>) for cooling, subsequently to an ion exchanger (<b>11</b>), then to a second heat exchanger (<b>12</b>) for heating and again to the PEM… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Method for operating a water electrolysis device | 7 |
| 2 | Method for operating a water electrolysis device | 3 |
| 3 | 一种柴油机氢基混合气体发生器 | 1 |
| 4 | Method for operating a water electrolysis device | 1 |
| 5 | Method for operating a water electrolysis device | 1 |
Ranked by total forward citations. Citation counts favour older and broadly cited patent families, and broad or adjacent patents may appear when they match the search scope. Treat this section as citation context, not as a curated list of the most topic-specific patents. Some patent titles may be shown in their original, non-English language where an accurate translation could not be guaranteed.
Assignee snapshot from the current evidence set
The applicants below are visible in this query result. Because the evidence set is relatively small, read this section as a directional snapshot rather than a full competitive ranking.
Hoeller Electrolyzer GmbH
Hoeller Electrolyzer GmbH holds 20 patent families, all concentrated in C25B electrolytic production sub-classes covering operational methods (C25B15), electrolysis fundamentals (C25B1), and cell hardware (C25B9). The top-cited patents in the corpus — all titled ‘Method for operating a water electrolysis device’ — originate from this portfolio, confirming that Hoeller’s filings define the prior-art baseline for the entire field. No momentum data indicates a recent acceleration, consistent with the post-peak lifecycle.
families: 20Shanghai Weishen Electronic Technology Co., Ltd.
Shanghai Weishen Electronic Technology Co., Ltd. holds 2 patent families with a notably broader technology spread than Hoeller, touching B60K (vehicle propulsion), C01B (inorganic compounds), and C25B (electrolysis) — suggesting a mobile or onboard hydrogen application angle rather than stationary electrolyzer systems. No momentum trend is recorded, placing this filer in a stable, low-volume position. Huadian Heavy Machinery is the only applicant with a recorded momentum signal, flagged as a new entrant with 1 recent family in C25B.
families: 2Frequently asked questions
The corpus contains 26 patent families in scope for PEM electrolyzer balance-of-plant technology across the global jurisdictions and time window analyzed.
Hoeller Electrolyzer GmbH is the clear leader with 20 patent families, focused on electrolytic production methods and cell hardware under the C25B class. No other applicant holds more than 2 families.
The field is in a decline phase. Annual filings peaked in 2018 at 9 families and have eased substantially since. The most recent years show very low recorded activity, though the last 18–24 months are subject to publication lag and final counts may be higher.
India leads with 8 patent records, followed by Australia and the United States each with 6, China with 3, Canada with 2, and one WIPO (PCT) filing. The India lead may reflect prosecution choices of specific filers rather than pure market priority.
No co-applicant collaborations are recorded in the corpus. Every filer has prosecuted independently, indicating a siloed innovation environment with no consortium-based IP structures evident in this dataset.
The sparsest branches relative to the visible C25B core are C10G (hydrocarbon refining, 1 record), B01D (separation processes, 1 record), B60K (vehicle propulsion, 2 records), and F02M (fuel supply, 2 records). C01B (non-metallic elements and inorganic compounds) has 3 records. These branches represent adjacent system-integration areas with thin current coverage.
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Disclaimer. This page is generated from PatSnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
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