PEM Fuel Cell & PEM Electrolyzer Patent Landscape
PEM Fuel Cell & PEM Electrolyzer Patent Landscape in 2026
The PEM fuel cell and electrolyzer space is in a growth phase, with annual filings trending upward and the field still understated in the most recent window due to publication lag. Siemens AG leads by a clear margin, and the top five filers collectively hold more than half the share among the hundred largest filers, signaling a concentrated competitive structure dominated by European industrials.
Siemens AG leads a concentrated European-industrial field
Siemens AG ranks first among all applicants, followed by Robert Bosch GmbH and W C Heraeus GmbH. The top five filers — Siemens, Bosch, Heraeus, Mercedes-Benz Group, and Hydrogenics — account for 56% of the combined total among the hundred largest filers, confirming a heavily concentrated competitive structure.
A clear tier gap separates the top two applicants from the rest of the ranking. Siemens AG holds 11 patent records and Robert Bosch GmbH holds 9, while W C Heraeus GmbH follows at 6 and the next group clusters at 5 or below. This compression means the gap between tier-one and tier-two players is narrow, but the drop to the broader field is steep.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | Siemens AG | 11 | |
| 2 | Robert Bosch GmbH | 9 | |
| 3 | W C Heraeus GmbH | 6 | |
| 4 | Mercedes-Benz Group AG | 5 | |
| 5 | Hydrogenics Corp | 5 | |
| 6 | General Motors LLC | 3 | |
| 7 | Shenyang Ligong University | 2 | |
| 8 | KINKELAAR MARK R | 2 | |
| 9 | Degussa Hüls AG | 2 | |
| 10 | UMICORE AG & CO KG | 2 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Zhejiang Haizhuo New Energy Technology Co Ltd | 1 | |
| 12 | Zhao Hongshan | 1 | |
| 13 | NMAM Institute of Technology (Nitte Deemed to be University) | 1 | |
| 14 | Indian Oil Corporation Ltd | 1 | |
| 15 | Hangzhou Gongshu District Edge Intelligence Innovation Research Institute | 1 | |
| 16 | Foamex Innovations Operating | 1 | |
| 17 | Ruqing (Qingdao) Energy Technology Co Ltd | 1 | |
| 18 | BUDINSKI MICHAEL K | 1 | |
| 19 | MATHIAS MARK F | 1 | |
| 20 | Tsinghua University | 1 |
The dominance of European industrial and automotive conglomerates — Siemens, Bosch, Heraeus, Mercedes-Benz, and Degussa Hüls — reflects early and sustained investment in membrane electrode assembly and electrolyzer stack technology. New entrants from. China and India are beginning to appear in the lower ranks, suggesting gradual geographic diversification of R&D activity.
Filings from 2024 onward are likely under-counted due to standard patent publication delays of 18–24 months; the apparent pause in 2025–2026 should not be read as a real decline. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Annual activity is rising and core IPC classes dominate the mix
The annual filing trend chart and the technology-composition chart together reveal a field accelerating on a multi-year basis, with the technology mix tightly anchored in two co-equal IPC classes. Minor adjacent branches represent a small but potentially meaningful tail of activity.
Annual filing trend
Filing activity was modest between 2017 and 2022, with a trough in 2018–2019, then rebounded through 2020–2022 before reaching a recorded peak of 7 patent records in 2024. The years 2025 and 2026 show lower counts, but those figures are understated by publication lag and should not be interpreted as a downturn. The overall multi-year trajectory confirms the growth stage characterization.
↗ Hover for values · click a bar to ask EurekaTechnology composition
C25B (Electrolytic production of compounds) and H01M (Batteries, cells and fuel cells) each account for 57 patent records, making them the co-dominant technical pillars of this corpus. Coating processes (B05D) and layered products (B32B) each contribute 4 records, while separation, catalysis, powder metallurgy, electric vehicle propulsion, inorganic compounds, refrigeration, and power grid applications each appear at 1–2 records — forming a sparse but diverse tail of adjacent activity.
↗ 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.
Diffusion media for use in a PEM fuel cell
A diffusion media is provided for implementation with a PEM fuel cell. The diffusion media is a permeable sheet that is rigid along a transverse axis, flexible along a lateral axis and has a substantially incompressible thickness. The diffusion media is able to be mass produced in large sheets and rolled along the lateral axis for transport and storage. The… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Improved diaphragm electrode unit for a PEM fuel c… | 79 |
| 2 | Gas diffusion layer containing inherently conducti… | 55 |
| 3 | Method for applying electrode layers on a tape-lik… | 55 |
| 4 | Control of a fluid flow in an electrochemical cell | 28 |
| 5 | Diffusion media for use in a PEM fuel cell | 23 |
| 6 | Gas diffusion layer containing inherently conducti… | 20 |
| 7 | Method and device for generating hydrogen and oxygen | 13 |
| 8 | 一种具有尾气能量回收功能的PEM燃料电池发电装置 | 10 |
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.
What the competitive structure means for R&D investment
Four structural signals — lifecycle stage, top-filer concentration, co-applicant relationships, and jurisdiction footprint — shape the risk and opportunity calculus for any organization entering or expanding in this space.
Growth stage with rising annual filings
The field is classified as Growth, with annual filings still rising and the most recent years understated by publication lag. A 100% recent-window growth rate confirms that activity is accelerating rather than plateauing. Entrants arriving now face established incumbents but can still carve positions in emerging sub-branches before the field matures further.
Lifecycle: GrowthHigh concentration; top five hold 56% of the lead-100 total
The top five filers account for 56% of the combined patent records among the hundred largest filers, indicating a field where a small number of European industrials set the technical agenda. The narrow gap between Siemens (11 records) and Bosch (9 records) suggests competitive pressure at the very top, but the steep drop to mid-tier applicants means new entrants must differentiate by sub-technology rather than compete head-on in the core stack.
High concentrationSiemens and W C Heraeus are the most active co-filers
The most active co-applicant pair is Siemens AG and W C Heraeus GmbH, sharing 6 collaborative patent records. Individual inventor Waidhas Manfred co-files with both Siemens (3 records) and Heraeus (2 records), as does Jeschonnek Bernd (2 records each), suggesting a tight inventor network bridging the two organizations. This cluster may indicate joint development of membrane or electrode coating technology that is not fully replicated by other players.
Co-filing clusterChina leads filings; PCT and EPO signal global ambition
China is the leading jurisdiction by patent records, followed by WIPO PCT filings and the European Patent Office. The United States ranks fourth. This distribution suggests that applicants are pursuing broad multi-regional coverage via PCT and EPO while prioritizing China as a key market or manufacturing destination. Australia, Canada, Spain, India, Japan, and South Korea are also present, reflecting a genuinely global filing strategy among the leading filers.
Multi-regionalGo beyond the landscape: Eureka’s TRIZ Solution agent breaks down an R&D problem and returns patented concept solutions, each with a technical approach and cited patent & literature evidence.
| Applicant | Collaborator | Co-filings |
|---|---|---|
| Siemens AG | W C Heraeus GmbH | 6 |
| WAIDHAS MANFRED | Siemens AG | 3 |
| WAIDHAS MANFRED | W C Heraeus GmbH | 2 |
| JESCHONNEK BERND | Siemens AG | 2 |
| JESCHONNEK BERND | W C Heraeus GmbH | 2 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Siemens AG and Robert Bosch GmbH lead across both electrolytic and fuel-cell branches
The two highest-ranked applicants share overlapping but distinguishable technology emphases, and Robert Bosch GmbH has shown a new-entrant momentum signal in the most recent period, indicating accelerating investment.
Siemens AG
Siemens AG holds 11 patent records, the highest count in the corpus. Its technology focus centers on C25B 9 (electrolytic cell design, 10 records) and H01M 8 (fuel cell stacks, 8 records), with secondary activity in C25B 1 (electrolytic production of inorganic compounds, 2 records). This profile reflects a dual-platform strategy covering both PEM electrolyzer architecture and fuel cell integration. Siemens is also the anchor of the field’s most active co-filing cluster, partnering with W C Heraeus GmbH on 6 shared records.
11 patent recordsRobert Bosch GmbH
Robert Bosch GmbH ranks second with 9 patent records and carries a new-entrant momentum signal, indicating its filings are concentrated in the most recent period relative to its prior base. Its technology focus spans C25B 9 (9 records), H01M 8 (9 records), and B32B 15 (layered metallic laminates, 4 records) — the last of these distinguishing Bosch from Siemens and suggesting active work on gas diffusion layer or bipolar plate laminate structures. This breadth across both core and adjacent branches makes Bosch the most technically diversified of the top-two players.
9 patent records| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Robert Bosch GmbH | 2 | ▲ new entrant |
Coating processes and separation technology are under-served adjacent branches
Several IPC branches adjacent to the dominant C25B and H01M classes carry low patent counts relative to their technical relevance to PEM systems. These are observations of relative sparsity; they represent plausible but unvalidated entry points that warrant further technical scoping before commitment.
B05D · Coating processes for electrode and membrane layers
B05D appears in 4 patent records, accounting for roughly 3% of the IPC-level corpus. Coating process innovation — particularly for catalyst-coated membranes and anti-corrosion layers on bipolar plates — is a known performance lever in PEM systems, yet the branch is sparsely populated here. Degussa Hüls AG is the only applicant with documented activity in B05D 7 within this corpus, suggesting limited competitive overlap. An entrant with thin-film or atomic-layer deposition expertise could find relatively open filing space in this branch.
Search this in Eureka →B01D · Separation processes for water and gas management
B01D covers filtration, membrane separation, and gas-liquid separation — all directly relevant to water management and gas purity in PEM electrolyzers and fuel cells — yet only 2 patent records appear in this branch within the corpus. No single dominant applicant is identified in B01D here, and the branch sits well below the activity levels of the core IPC classes. Organizations specializing in membrane separation or water purification technology may find a realistic entry path by combining separation process IP with PEM-specific system integration claims.
Search this in Eureka →How leading applicants differ across technology routes
Strength of each leader across the main technology routes.
| Player | H01M 8 · Batteries, cells & fuel cells | C25B 9 · Electrolytic production of compounds | H01M 4 · Batteries, cells & fuel cells | C25B 1 · Electrolytic production of compounds | C25B 11 · Electrolytic production of compounds |
|---|---|---|---|---|---|
| Robert Bosch GmbH | Strong · 9 | Strong · 9 | Absent | Moderate · 3 | Absent |
| Siemens AG | Strong · 8 | Strong · 10 | Absent | Emerging · 2 | Absent |
| Foamex Innovations Operating | Strong · 5 | Absent | Strong · 5 | Absent | Strong · 5 |
| W C Heraeus GmbH | Strong · 6 | Strong · 6 | Absent | Absent | Absent |
| General Motors LLC | Strong · 4 | Absent | Strong · 4 | Absent | Strong · 4 |
| Mercedes-Benz Group AG | Strong · 5 | Strong · 5 | Absent | Absent | Absent |
| Hydrogenics Corp | Strong · 5 | Strong · 5 | Absent | Absent | Absent |
Frequently asked questions
The corpus covers 25 patent families. This is a focused dataset reflecting a specific intersection of PEM fuel cell and PEM electrolyzer technology rather than the broader hydrogen or fuel cell field.
Siemens AG leads with 11 patent records, ahead of Robert Bosch GmbH at 9 and W C Heraeus GmbH at 6. These three German industrial and materials companies occupy the top three positions.
The field is classified as Growth. Annual filings are still rising and the most recent filing years are under-counted due to publication lag, so the true current activity level is likely higher than the raw counts suggest.
China leads with 17 patent records, followed by WIPO PCT (12), the European Patent Office (10), and the United States (9). Australia, Canada, Spain, India, Japan, and South Korea also appear, confirming a multi-regional filing strategy.
The most-cited work relates to an improved diaphragm electrode unit for a PEM fuel cell (79 citations), a gas diffusion layer containing inherently conductive polymer (55 citations), and a method for applying electrode layers on a tape-like backing (55 citations). These works anchor the field’s foundational membrane electrode assembly technology.
B05D (coating processes) and B01D (separation processes) are the sparsest adjacent branches, each holding 2–4 patent records. Both are technically relevant to PEM systems — coating for catalyst and plate layers, separation for water and gas management — and show limited incumbent overlap, making them observable areas of relative sparsity worth further scoping.
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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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