EDLC Electrical Testing Patent Landscape 2026
EDLC electrical testing is a concentrated, mature field dominated by a small cluster of Japanese capacitor manufacturers, with Japan accounting for the clear majority of filings. Annual volume peaked around 2020 and has since eased, placing the field in a decline phase — though adjacent branches in power systems integration and nanotechnology remain sparsely filed and technically relevant.
Panasonic and Tokin lead a tightly held Japanese-centric field
The EDLC electrical testing landscape is highly concentrated among established Japanese electronics manufacturers. Panasonic Holdings Corp and Tokin Corp share the top position, each holding 20 patent records, followed closely by NEC Corp with 19 patent records — making the three leaders virtually indistinguishable in size at the top of the ranking.
The top five filers account for 41% of the combined total among the hundred largest filers, a level of concentration that signals a mature, entrenched competitive structure with limited room for new entrants to overtake incumbents through incremental filing alone.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | Panasonic Holdings Corp | 20 | |
| 2 | Tokin Corp | 20 | |
| 3 | NEC Corporation | 19 | |
| 4 | AGC Inc | 11 | |
| 5 | Elna Co Ltd | 9 | |
| 6 | Kyocera AVX Components Corp | 6 | |
| 7 | Carver Scientific Inc | 5 | |
| 8 | Atlas Power Technologies Inc | 4 | |
| 9 | Taiyo Yuden KK | 4 | |
| 10 | Sustainable Energy Technologies Inc | 4 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Kyocera Corp | 4 | |
| 12 | Luxon Energy Devices Corp | 3 | |
| 13 | Murata Manufacturing Co Ltd | 3 | |
| 14 | MinebeaMitsumi Inc | 3 | |
| 15 | Gegadyne Energy Labs Pvt Ltd | 3 | |
| 16 | Maxwell Technologies Global LLC | 2 | |
| 17 | Nanotek Instruments Inc | 2 | |
| 18 | FastCAP Systems Corp | 2 | |
| 19 | Indian Space Research Organisation | 2 | |
| 20 | Marcon Electronics Co Ltd | 2 |
The dominance of Japanese firms — Panasonic, Tokin, NEC, AGC, and Elna — reflects the historical manufacturing and innovation base for Japan. Their sustained presence at the top indicates that core electrical testing IP is tightly held and unlikely to shift significantly without a disruptive technology entry.
Filings from approximately the last 18 to 24 months are subject to publication lag and are likely under-counted; the most recent annual figures should be read with that caveat in mind. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Activity peaked in 2020 and has eased; capacitor IP dominates but adjacent branches show gaps
Two lenses reveal the field’s current state: the annual filing trend shows a field that peaked and has since contracted, while the technology composition chart confirms that core capacitor IP (H01G) commands the overwhelming share of activity, leaving several adjacent classes underserved.
Annual filing trend
Annual filings reached a visible peak in 2020 with 10 patent families, then declined to the 3–5 range through 2023–2024. The 2025 count of 8 and the 2026 count of 2 should be treated as preliminary given typical publication lag of 18–24 months; they do not yet reflect a confirmed recovery. The overall recent-window growth rate is negative at -35%, consistent with a post-peak decline trajectory.
↗ Hover for values · click a bar to ask EurekaTechnology composition
H01G (Capacitors) accounts for the large majority of IPC assignments, reflecting the field’s tight focus on capacitor device characterization. G01R (Electric and magnetic measurement) is the next most active branch and is the only substantial measurement-specific class. Branches such as H02J (Power supply and grid systems), H01M (Batteries and fuel cells), B82Y (Nanotechnology), and G06F (Digital data processing) each carry single-digit counts, marking them as adjacent and underserved relative to the core.
↗ 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.
Electric double-layer capacitor and method for pre…
An electric double-layer capacitor includes a cell structure formed by laminating basic cells in series one on another. Each of the basic cells includes a pair of collectors, a separator disposed between said collectors, gaskets disposed at peripheral edges of said pair of collectors and said separator to define a pair of closed spaces, and a pair of… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Supercapacitor with high energy density | 119 |
| 2 | Cylindrical high voltage supercapacitor having two… | 71 |
| 3 | High capacitance electric double-layer capacitor | 59 |
| 4 | Electric double-layer capacitor | 46 |
| 5 | Electric double-layer capacitor | 38 |
| 6 | Electric double-layer capacitor | 31 |
| 7 | Electric double-layer capacitor | 27 |
| 8 | Cylindrical high voltage supercapacitor and method… | 26 |
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 patent structure means for R&D positioning
The combination of declining annual activity, heavy concentration, and a narrow technology footprint creates a clear picture for R&D decision-makers: the core EDLC testing space is mature and occupied, but adjacent functional branches remain open.
Decline phase — annual volume has eased from its 2020 peak
The lifecycle evidence places EDLC electrical testing in a Decline stage. Annual filings peaked in 2020 at 10 patent families and have eased back since, with the recent-window growth rate at –35%. New entrants face a shrinking filing base and an entrenched set of incumbents who have already secured core IP positions over the preceding decade.
Lifecycle: DeclineTop three filers are near-equal and collectively define the field
Panasonic Holdings Corp, Tokin Corp, and NEC Corp each hold between 19 and 20 patent records, creating an unusually flat top tier. AGC Inc (11 records) and Elna Co Ltd (9 records) form a clear second tier. The top five filers’ 41% share of the hundred largest filers’ combined total signals that any new entrant must differentiate technically rather than compete on volume.
High concentrationAGC and Elna are the only documented co-filers
Evidence shows a single active co-filing relationship: AGC Inc and Elna Co Ltd have filed together on 9 patent records, making them the most active collaboration pair in the corpus. No other co-applicant pairs are identified in the evidence. This narrow collaboration pattern suggests the field largely develops through independent corporate R&D rather than consortium or cross-institutional programs.
Limited co-filingJapan is the dominant jurisdiction; US and emerging markets are secondary
Japan accounts for 89 patent records, the clear lead jurisdiction by a wide margin. The United States follows at 19, with India at 16 and China at 15 — a notable presence of emerging-market filings that likely reflects growing industrial EDLC adoption in those regions. PCT (WIPO) filings at 12 and EPO at 7 indicate selective but not broad international protection strategies among the leading filers.
Japan-centricGo 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 |
|---|---|---|
| AGC Inc | Elna Co Ltd | 9 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Panasonic and Tokin lead on core capacitor IP; Kyocera AVX stands apart on measurement testing
The top two players share the same filing count and nearly identical technology focus, while Kyocera AVX Components Corp occupies a distinct niche in electrical measurement — the branch most directly tied to the ‘testing’ dimension of this landscape.
Panasonic Holdings Corp
Panasonic Holdings Corp holds 20 patent records, tied for first with Tokin Corp. Its technology focus is concentrated entirely on H01G 11 and H01G 9 (capacitor subclasses), reflecting a position built on core EDLC device IP rather than testing instrumentation. No momentum data for Panasonic is available in the evidence to indicate recent trajectory.
patent records: 20Kyocera AVX Components Corp
Kyocera AVX Components Corp holds 6 patent records and, notably, is the only top-tier applicant whose technology emphasis falls entirely within G01R (Electric and magnetic measurement subclasses G01R 19, G01R 27, and G01R 31), making it the field’s primary specialist in measurement and testing methodology proper. Its momentum is flagged as a new entrant in the recent period, though its 1 recent filing indicates this is from a small base.
patent records: 6| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Kyocera AVX Components Corp | 1 | ▲ new entrant |
Power systems integration and nanotechnology are under-served relative to the core
Five IPC branches adjacent to the dominant H01G core each carry fewer than 13 patent records and together represent less than 5% of all IPC assignments. Their low density, combined with plausible technical connections to EDLC testing, makes them worth monitoring as potential entry points.
H02J · Power supply and grid systems
With only 12 patent records, H02J is the largest of the adjacent under-served branches. EDLC modules are increasingly deployed in grid stabilization and uninterruptible power supply architectures, where testing under realistic load conditions (charge/discharge cycling, transient response) is a distinct technical problem from device-level characterization. The entry path is relatively direct for firms already active in G01R measurement or power electronics.
Search this in Eureka →B82Y · Nanotechnology applications
With only 5 patent records, B82Y is the sparsest branch in the top white-space list. Nanostructured electrode materials — carbon nanotubes, graphene — are an active area of EDLC materials research, and characterization methods for nano-scale electrodes (BET surface area, impedance spectroscopy at nanoscale) are not yet well covered in this corpus. The entry path requires materials science expertise alongside electrical testing methodology, making it a higher-barrier but lower-crowding opportunity.
Search this in Eureka →How leaders differ by technology route
Route coverage across the main technology branches in the current evidence set.
| Player | H01G 11 · Capacitors | H01G 9 · Capacitors | G01R 31 · Electric & magnetic measurement | G01R 27 · Electric & magnetic measurement | H02J 7 · Power supply & grid systems |
|---|---|---|---|---|---|
| NEC Corporation | Strong · 24 | Strong · 24 | Absent | Absent | Absent |
| Panasonic Holdings Corp | Strong · 20 | Strong · 20 | Absent | Absent | Absent |
| Tokin Corp | Strong · 14 | Strong · 12 | Absent | Absent | Absent |
| AGC Inc | Strong · 11 | Strong · 11 | Absent | Absent | Absent |
| Elna Co Ltd | Strong · 9 | Strong · 9 | Absent | Absent | Absent |
| Kyocera AVX Components Corp | Absent | Absent | Strong · 6 | Strong · 6 | Absent |
Frequently asked questions
The evidence corpus covers 56 patent families in EDLC electrical testing across the global filing landscape.
Panasonic Holdings Corp and Tokin Corp are tied at the top with 20 patent records each, followed closely by NEC Corp with 19. AGC Inc (11) and Elna Co Ltd (9) round out the top five.
The field is in a Decline stage. Annual filings peaked in 2020 and have eased back since, with a recent-window growth rate of -35%. The most recent 18–24 months of data are subject to publication lag and should be read with caution.
Japan is the dominant jurisdiction by a wide margin at 89 patent records. The United States follows at 19, with India at 16, China at 15, WIPO PCT at 12, and EPO at 7.
H02J (Power supply and grid systems) at 12 patent records and B82Y (Nanotechnology applications) at 5 patent records are among the most sparsely filed adjacent branches relative to the dominant H01G capacitor class, which carries 152 patent records.
Evidence shows one active co-filing relationship: AGC Inc and Elna Co Ltd have co-filed on 9 patent records, making them the only documented collaboration pair in the corpus. The field otherwise develops largely through independent corporate IP programs.
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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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