Li-Ion Capacitor (Hybrid) Patent Landscape 2026
The lithium-ion hybrid capacitor field is heavily concentrated, with Sumitomo Electric Industries and its affiliated entity Sumitomo Electric Toyama jointly accounting for the dominant share of ranked filers. Annual filing volume has plateaued near its 2021 peak, signaling a maturing but still active competitive space.
Sumitomo Electric leads a concentrated field with a clear tier gap below the top two
Sumitomo Electric Industries holds the top position in the applicant ranking, followed closely by its affiliate Sumitomo Electric Toyama, together forming an integrated bloc at the head of the field. Subaru Corporation ranks third, with Corning Inc. and JM Energy Corporation rounding out the top five.
The top five filers account for 43% of the combined total among the hundred largest filers, indicating meaningful but not overwhelming concentration. A visible tier gap separates the top two Sumitomo entities from the remaining applicants, whose individual counts fall off sharply after the top five.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | Sumitomo Electric Industries, Ltd. | 50 | |
| 2 | Sumitomo Electric Toyama Co., Ltd. | 46 | |
| 3 | Subaru Corporation | 23 | |
| 4 | Corning Incorporated | 17 | |
| 5 | JM Energy Corporation | 10 | |
| 6 | Semicon Energy Lab Co., Ltd. | 9 | |
| 7 | Florida State University Research Foundation, Inc. | 8 | |
| 8 | General Capacitor LLC | 8 | |
| 9 | DKS Co., Ltd. | 7 | |
| 10 | Musashi Energy Solutions Co., Ltd. | 7 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Fundacion Centro de Investigacion Cooperativa de Energias Alternativas (CIC energiGUNE) | 7 | |
| 12 | Vinatech Co., Ltd. | 6 | |
| 13 | Godi India Pvt. Ltd. | 6 | |
| 14 | Panasonic Intellectual Property Management Co., Ltd. | 5 | |
| 15 | Ningbo CRRC New Energy Technology Co., Ltd. | 5 | |
| 16 | Komatsu Ltd. | 4 | |
| 17 | China Electronics Technology Group Corporation No. 18 Research Institute | 4 | |
| 18 | SPEL Technologies Pte. Ltd. | 4 | |
| 19 | China Aviation Lithium Battery (Luoyang) Co., Ltd. | 4 | |
| 20 | Resonac Corporation | 4 |
The Sumitomo bloc’s dominance suggests deep institutional expertise in electrode materials and cell architecture for hybrid capacitors; challengers from automotive (Subaru), specialty glass and materials (Corning), and dedicated capacitor developers (JM Energy, General Capacitor) occupy distinct technical niches rather than competing head-on across all routes.
Filings from the most recent 18–24 months are subject to publication lag and will be under-counted in the current dataset; the apparent softening in 2024–2026 data should not be interpreted as a structural decline. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Filing volume has plateaued since 2021; capacitor-class patents dominate the technology mix
Two lenses frame the field’s current state: a multi-year filing trend that shows activity plateauing after a 2021 peak, and a technology composition skewed heavily toward capacitor and battery cell classifications with a long tail of adjacent branches.
Annual filing trend
Annual filings rose from 13 in 2017 to a peak of 18 in 2021, then oscillated between 10 and 17 through 2023 before declining in the most recent data points — a pattern consistent with plateau-stage maturity. The 2024–2026 figures are subject to publication lag and should be treated as provisional undercounts rather than evidence of retreat.
↗ Hover for values · click a bar to ask EurekaTechnology composition
H01G (Capacitors) dominates the IPC mix by a wide margin, reflecting the core device classification. H01M (Batteries, cells and fuel cells) is the second-largest branch, consistent with the hybrid architecture that blends capacitor and lithium-ion battery principles. All remaining branches — including C01B (inorganic compounds), C07C and C07D (organic chemistry), and B32B (layered products) — hold small shares, pointing to the field’s concentrated technical focus with only modest diversification into materials chemistry and structural innovations.
↗ 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 pre-lithiating lithium-ion capacitor
A technique for pre-lithiating a lithium-ion capacitor includes preparing multiple cathodes, anodes, and separators, stacking them, injecting electrolyte, and performing a multi-step charging process. Some anodes have surfaces coated with a lithium foil of 10-40 μm thickness, while others remain uncoated, and they alternate in the stack. Cathodes may… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Lithium-ion capacitor | 110 |
| 2 | Power storage device, lithium-ion secondary batter… | 59 |
| 3 | Three-dimensional network aluminum porous body, el… | 57 |
| 4 | Method of negative electrode pre-lithiation for li… | 52 |
| 5 | 一种锂离子电容器用负极片及其制备方法 | 38 |
| 6 | Electricity storage device with explosion-proof fu… | 37 |
| 7 | Negative electrode film for lithium-ion capacitor,… | 37 |
| 8 | Lithium-ion capacitor | 33 |
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 decisions
Four structural observations — maturity stage, concentration, collaboration patterns, and geographic spread — together shape the risk and opportunity profile for new entrants and incumbents alike.
Field is at a plateau stage, not in decline
The lifecycle evidence indicates annual filings have plateaued near their 2021 peak, placing the field in a maturity stage. This means the core device architecture is well-charted and the low-hanging IP is largely claimed. R&D investment should target differentiated sub-problems — electrode pre-lithiation methods, porous current-collector design, and electrolyte composition — where the top-cited patents suggest remaining technical headroom.
Maturity · PlateauTop-two bloc leaves narrow room for undifferentiated entry
The top five filers hold 43% of the combined total among the hundred largest filers, and the Sumitomo pair alone accounts for the two leading positions. New entrants who seek to compete on mainstream electrode or cell-architecture claims face a dense prior-art landscape. Differentiation through materials chemistry (C01B, C07C, C07D branches) or system-level integration (H02J) offers a more open path.
Concentration · HighSumitomo entities co-file prolifically; one academia-industry pair stands out
The strongest co-filing relationship in the dataset is between Sumitomo Electric Industries and Sumitomo Electric Toyama, with 42 joint records — effectively an integrated R&D unit. A second notable pairing links General Capacitor LLC with the Florida State University Research Foundation across 6 joint records, representing the field’s most prominent academia-industry collaboration. Other significant co-inventor clusters (Sakaida Hideaki, Ota Hajime, Okuno Kazuki, Nishimura Junichi) are all tied into the Sumitomo network.
Collaboration · Sumitomo-ledChina and the US are the primary filing destinations; Asia-Pacific dominates overall
China leads jurisdiction coverage, followed closely by the United States. South Korea, WIPO (PCT), Japan, and Europe (EPO) form the next tier, with India emerging as a notable seventh destination. This spread reflects both large domestic markets and the use of PCT as a gateway for global protection. Taiwan, Canada, and Norway account for a small tail of filings.
Geography · China & US co-leadGo 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 |
|---|---|---|
| Sumitomo Electric Industries, Ltd. | Sumitomo Electric Toyama Co., Ltd. | 42 |
| SAKAIDA HIDEAKI | Sumitomo Electric Toyama Co., Ltd. | 8 |
| SAKAIDA HIDEAKI | Sumitomo Electric Industries, Ltd. | 8 |
| OTA HAJIME | Sumitomo Electric Toyama Co., Ltd. | 8 |
| OTA HAJIME | Sumitomo Electric Industries, Ltd. | 8 |
| OKUNO KAZUKI | Sumitomo Electric Toyama Co., Ltd. | 8 |
| OKUNO KAZUKI | Sumitomo Electric Industries, Ltd. | 8 |
| NISHIMURA JUNICHI | Sumitomo Electric Toyama Co., Ltd. | 8 |
| NISHIMURA JUNICHI | Sumitomo Electric Industries, Ltd. | 8 |
| General Capacitor LLC | Florida State University Research Foundation, Inc. | 6 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Sumitomo Electric and its Toyama affiliate lead; Subaru and Corning occupy distinct niches
The top applicants span Japanese industrial conglomerates, an automotive OEM, a US specialty-glass company, and dedicated capacitor developers — each with a different technical emphasis within the hybrid capacitor stack.
Sumitomo Electric Industries
Sumitomo Electric Industries holds the top position with 50 patent records. Its technology focus spans H01G 11 (hybrid capacitors), H01M 4 (electrode materials), and H01M 10 (secondary cell systems), reflecting end-to-end coverage of the hybrid capacitor stack. The entity operates as part of a tightly integrated co-filing bloc with Sumitomo Electric Toyama; applicant momentum data is not separately available for this filer in the current evidence set.
patent records: 50Subaru Corporation
Subaru Corporation ranks third with 23 patent records, making it the highest-ranked non-Sumitomo filer. Its focus sits across H01G 11, H01G 9 (electrolytic capacitors), and H01M 10, suggesting an automotive integration angle — particularly for hybrid vehicle power systems — rather than fundamental cell chemistry. Applicant momentum figures are not available in the current evidence set.
patent records: 23Under-served adjacent branches in materials chemistry and structural design
Several IPC branches appear at low shares relative to the dominant H01G and H01M classes, representing areas where hybrid capacitor patent activity is sparse. Three of these carry plausible technical relevance and merit monitoring.
C01B · Non-metallic elements and inorganic compounds
C01B holds a 4% share of IPC records in this corpus — the largest of the sparse branches — pointing to limited but present activity in carbon allotropes and inorganic electrode precursors such as silicon or sulfur compounds. Given that pre-lithiation and anode performance are recurring themes in the top-cited patents, novel inorganic anode or separator materials represent a technically grounded entry path. Researchers with expertise in activated carbon, graphene, or silicon oxides could extend existing work without colliding with the densely claimed H01G 11 core.
Search this in Eureka →C07C / C07D · Acyclic, carbocyclic and heterocyclic organic compounds
C07C and C07D each account for roughly 1% of IPC records, signaling sparse coverage of organic electrolyte solvents, ionic liquids, and binder systems specific to hybrid capacitors. Electrolyte formulation is a known performance lever — affecting ion transport, pre-lithiation efficiency, and operating temperature range — yet the patent record here is thin. Entry via novel electrolyte additives or heterocyclic ligand-based electrolytes is technically adjacent to the main cell-architecture work and faces a low prior-art density in this corpus.
Search this in Eureka →How the leading filers differ across technology routes
Route coverage across the main technology branches in the current evidence set.
| Player | H01G 11 · Capacitors | H01M 4 · Batteries, cells & fuel cells | H01M 10 · Batteries, cells & fuel cells | H01G 9 · Capacitors | C01B 32 · Non-metallic elements & inorganic compounds |
|---|---|---|---|---|---|
| Sumitomo Electric Industries, Ltd. | Strong · 46 | Strong · 41 | Moderate · 22 | Moderate · 17 | Absent |
| Sumitomo Electric Toyama Co., Ltd. | Strong · 42 | Strong · 41 | Strong · 22 | Moderate · 17 | Absent |
| Subaru Corporation | Strong · 23 | Moderate · 11 | Strong · 12 | Strong · 20 | Absent |
Frequently asked questions
The current analysis covers 119 patent families in scope. This represents the deduplicated family count; individual patent records across jurisdictions will exceed this figure as a single family can be filed in multiple countries.
Sumitomo Electric Industries is the top-ranked filer with 50 patent records, followed by its affiliate Sumitomo Electric Toyama with 46 patent records. Together these two entities form the dominant bloc in the field.
China and the United States are the two leading jurisdictions, followed by South Korea, WIPO (PCT), Japan, and Europe (EPO). India has emerged as a notable seventh destination, with Taiwan, Canada, and Norway accounting for a smaller tail of filings.
The field is at a maturity/plateau stage. Annual filings peaked in 2021 and have since oscillated without a clear upward trend. This signals that the core device architecture is well-established and the primary IP positions are largely staked out, though targeted sub-fields remain open.
Yes. The strongest co-filing relationship links Sumitomo Electric Industries and Sumitomo Electric Toyama across 42 joint records, functioning as an integrated R&D unit. The most prominent external collaboration pairs General Capacitor LLC with the Florida State University Research Foundation across 6 joint records — the field’s leading academia-industry tie.
The sparsest IPC branches relative to the dominant H01G and H01M classes are C01B (inorganic compounds and carbon-based materials), C07C and C07D (organic electrolyte and additive chemistry), and B32B (layered electrode or separator structures). These branches each hold low record shares and offer technically adjacent entry paths without directly competing with the dense core claims.
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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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