Membrane Capacitive Deionization (MCDI) Patent Landscape
The MCDI patent field is in a Growth stage, with multi-year filing volume up significantly from the prior window, though annual output peaked in 2023 and the most recent years are subject to publication lag. Activity is moderately concentrated among academic and institutional filers, with DWI Leibniz Institute for Interactive Materials leading the ranking and China accounting for the dominant share of jurisdictional filings.
DWI Leibniz leads a moderately concentrated field dominated by academic filers
DWI Leibniz Institute for Interactive Materials holds the top position in the applicant ranking, followed by TDS Select LLC and a cluster of universities — University of Kentucky Research Foundation, Hohai University, NewSouth Innovations, and Jiangsu UNSW CTET (Yixing) — each tied at the next tier. The field is driven primarily by academic and research institutions rather than large industrials.
The top five filers collectively account for 22% of the combined patent records from the hundred largest filers — a moderate concentration level that signals no single entity has locked up the space. A meaningful second tier of university and SME filers keeps the competitive landscape open.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | DWI Leibniz Institute for Interactive Materials | 13 | |
| 2 | TDS Select LLC | 7 | |
| 3 | University of Kentucky Research Foundation | 6 | |
| 4 | Hohai University | 6 | |
| 5 | NewSouth Innovations Pty Ltd | 6 | |
| 6 | Jiangsu UNSW CTET (Yixing) Co. Ltd | 6 | |
| 7 | East China University of Technology | 5 | |
| 8 | Zhejiang University of Technology | 4 | |
| 9 | Jiangsu Maymuse Environmental Technology Co. Ltd | 4 | |
| 10 | Siontech | 4 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | JIANGSU UNIV OF SCI & TECH | 4 | |
| 12 | Jilin University | 4 | |
| 13 | TIANJIN UNIV OF SCI & TECH | 3 | |
| 14 | Voltea | 3 | |
| 15 | BEIJING HUA YAN BANG SCI & TECH | 3 | |
| 16 | Qinghai Salt Lake Industry | 3 | |
| 17 | Qinghai Institute of Salt Lakes, Chinese Academy of Sciences | 3 | |
| 18 | Gardiner Jack C | 3 | |
| 19 | UNIST (ULSAN NAT INST OF SCI & TECH) | 2 | |
| 20 | Merida Donis Walter Robert | 2 |
The leaders’ positions suggest that fundamental electrode and membrane chemistry remains an active research frontier rather than a mature industrial domain. The presence of joint-venture and spin-out entities alongside universities hints that commercialization pathways are beginning to form.
Filings from 2024 onward are likely undercounted due to typical patent publication lag of 18–24 months; apparent softness in those years should not be read as a structural slowdown. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Multi-year growth intact; water-treatment classification dominates the technology mix
The annual filing chart shows how activity has evolved since 2017, while the technology composition chart reveals which IPC branches capture the bulk of MCDI patent activity.
Annual filing trend
Filing volume rose from 6 records in 2017 to a peak of 24 in 2023, reflecting a 57% uplift in recent-window versus prior-window counts. The dip in 2024 and 2025 is consistent with normal publication lag and should not be interpreted as a genuine decline. The overall trajectory confirms that the field is still expanding on a multi-year basis, though annual volume has eased from its 2023 peak.
↗ Hover for values · click a bar to ask EurekaTechnology composition
C02F (Water & wastewater treatment) dominates the IPC mix by a wide margin, confirming that desalination and water-quality applications anchor MCDI innovation. B01D (Separation processes) forms a meaningful secondary cluster, while branches such as C25B (Electrolytic production), H01G (Capacitors), and H01M (Batteries, cells & fuel cells) each represent small but structurally distinct adjacent areas.
↗ 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.
Desalination systems of photovoltaic direct-driven…
The present disclosure relates to a desalination system of photovoltaic direct-driven membrane capacitive deionization. The system includes a photovoltaic direct-driven group and a municipal power grid-connected group. The photovoltaic direct-driven group includes a photovoltaic power collection unit, a power storage unit, a direct-driven power monitoring… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Method and apparatus for integrated water deioniza… | 143 |
| 2 | Apparatus for integrated water deionization, elect… | 130 |
| 3 | Method and apparatus for integrated water deioniza… | 70 |
| 4 | 一种MOF衍生多孔碳/石墨烯复合电极材料的制备及应用 | 31 |
| 5 | Apparatus and method for continuous water desalina… | 30 |
| 6 | 通过电容去离子进行连续的水脱盐和离子分离的方法及其单模块流动电极装置 | 29 |
| 7 | Ion-Selective Capacitive Deionization Composite El… | 28 |
| 8 | 一种利用膜电容去离子连续废水处理装置 | 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 competitive structure means for R&D strategy
MCDI sits at the intersection of membrane chemistry, electrochemistry, and water treatment engineering. The landscape’s academic-heavy composition and moderate concentration suggest windows for differentiated entry, particularly in adjacent technical branches.
Growth stage with 2023 peak; multi-year trajectory still positive
The field is classified as Growth, with recent-window filing volume 57% above the prior window. Annual output peaked in 2023 and has since eased, though this partly reflects publication lag. For R&D planners, this stage means foundational IP is still being established and freedom-to-operate positions remain contestable.
Growth stageModerate concentration; no dominant industrial player has locked the field
The top five filers hold 22% of patent records among the hundred largest filers, and the leading entity — DWI Leibniz Institute for Interactive Materials — holds the top position with a count that is roughly double the next tier. The absence of a dominant industrial giant means new entrants with differentiated electrode or membrane designs can realistically establish meaningful positions.
Open competitive fieldJiangsu UNSW CTET and NewSouth Innovations anchor the most active co-filing partnership
The most active co-applicant pair is Jiangsu UNSW CTET (Yixing) Co. Ltd and NewSouth Innovations Pty Ltd, with 6 jointly filed records — reflecting a structured industry-university technology-transfer relationship. Jiangsu Maymuse Environmental Technology Co. Ltd has secondary co-filing relationships with Changzhou University and the Changzhou Sunan Water Environment Research Institute. These clusters suggest that partnering with Australian or Chinese university IP-commercialization offices is a viable entry mechanism.
Industry-university JVsChina leads filings; US and South Korea form a meaningful secondary tier
China accounts for the largest share of jurisdictional patent records, reflecting concentrated domestic R&D investment and manufacturing ambition in water treatment. The United States and South Korea each form a secondary filing tier, with Europe (EPO) and WIPO (PCT) providing international coverage routes. Notably, PCT filings remain relatively sparse, implying that many innovations have not yet been internationalized — a risk for any player seeking global freedom to operate.
China-led, PCT sparseGo 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 |
|---|---|---|
| Jiangsu UNSW CTET (Yixing) Co. Ltd | NewSouth Innovations Pty Ltd | 6 |
| Jiangsu Maymuse Environmental Technology Co. Ltd | Changzhou University | 2 |
| Jiangsu Maymuse Environmental Technology Co. Ltd | Changzhou Sunan Water Environment Research Institute Co. Ltd | 1 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
DWI Leibniz anchors the field; new entrants from China and Australia are accelerating
The top two ranked players represent contrasting strategic profiles: a European research institute focused on fundamental membrane materials, and a US-based applied technology company with a system-integration emphasis.
DWI Leibniz Institute for Interactive Materials
Holds the top position in the ranking and concentrates its portfolio almost entirely in C02F 1 (water and wastewater treatment), with secondary activity in B01D 15 (separation processes). The institute’s portfolio reflects deep expertise in ion-exchange membrane chemistry and electrode design. Momentum data for this entity is not separately listed in the recent-entrant signals, indicating an established rather than emerging trajectory.
13 patent recordsTDS Select LLC
Ranks second overall with 7 patent records and is not flagged as a new entrant in the momentum data, suggesting a sustained rather than burst-mode filing strategy. Evidence on its specific IPC focus within the top-applicant technology breakdown is pending for this entity specifically; its position in the ranking nonetheless places it ahead of a large cluster of university filers.
7 patent records| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Hohai University | 1 | ▲ new entrant |
| Jiangsu UNSW CTET (Yixing) Co. Ltd | 3 | ▲ new entrant |
| NewSouth Innovations Pty Ltd | 3 | ▲ new entrant |
| Gardiner Jack C | 3 | ▲ new entrant |
| Jiangsu Maymuse Environmental Technology Co. Ltd | 2 | ▲ new entrant |
| East China University of Technology | 5 | ▲ new entrant |
Under-served branches in electrolytic chemistry and AI-driven process control
Several IPC branches appear at low patent-record counts relative to the dominant C02F cluster. Two stand out for their plausible technical connection to MCDI and their sparse current coverage.
G06N · Computing based on AI models
With only 3 patent records and a 1% share of the IPC distribution, AI-model-based process control for MCDI systems is structurally under-served. As MCDI scales to municipal and industrial deployments, adaptive regeneration scheduling, fouling prediction, and real-time ion-selectivity optimization are credible engineering problems where algorithmic IP could add durable value. Entry paths include co-development with water-utility data owners or embedding into existing MCDI hardware platforms.
Search this in Eureka →C25B · Electrolytic production of compounds
C25B records number 9 — the largest of the sparse adjacent branches — and are notably concentrated in the Siontech portfolio, which pairs C25B 11 and C25B 9 with its MCDI water-treatment work. The intersection of MCDI with in-situ electrolytic generation of disinfectants or reagents represents a technically coherent but lightly patented area. An entrant with electrode-coating or cell-architecture expertise could establish an early position here before the branch attracts broader attention.
Search this in Eureka →How leaders differ by IPC technology route
Route coverage across the main technology branches in the current evidence set.
| Player | C02F 1 · Water & wastewater treatment | B01D 61 · Separation processes (filtration etc.) | C02F 101 · Water & wastewater treatment | C02F 103 · Water & wastewater treatment | C02F 9 · Water & wastewater treatment |
|---|---|---|---|---|---|
| DWI Leibniz Institute for Interactive Materials | Strong · 13 | Absent | Absent | Emerging · 1 | Absent |
| Gardiner Jack C | Strong · 6 | Strong · 5 | Absent | Moderate · 2 | Absent |
| TDS Select LLC | Strong · 4 | Strong · 4 | Absent | Absent | Absent |
| Hohai University | Strong · 6 | Absent | Absent | Absent | Emerging · 1 |
| Jiangsu University of Science and Technology | Absent | Absent | Absent | Strong · 4 | Strong · 3 |
| NewSouth Innovations Pty Ltd | Strong · 6 | Absent | Absent | Absent | Absent |
| Jiangsu UNSW CTET (Yixing) Co. Ltd | Strong · 6 | Absent | Absent | Absent | Absent |
Frequently asked questions
The analysis covers 102 patent families in scope. The applicant ranking draws on patent records from the top 100 filers, which can exceed the family count because a single family may be counted under multiple classification records.
DWI Leibniz Institute for Interactive Materials (Germany) leads the ranking with 13 patent records, ahead of TDS Select LLC with 7 and a cluster of universities each holding 6.
The field is classified as Growth. Recent-window filing volume is 57% above the prior window on a multi-year basis. Annual output peaked in 2023 and has since eased, partly due to publication lag in 2024 and 2025 data.
China has the highest number of patent records, followed by the United States, South Korea, and Europe (EPO). WIPO (PCT) filings are relatively limited, suggesting that many innovations have not yet been fully internationalized.
The most active co-filing pair is Jiangsu UNSW CTET (Yixing) Co. Ltd and NewSouth Innovations Pty Ltd, with 6 jointly filed records. Jiangsu Maymuse Environmental Technology Co. Ltd also co-files with Changzhou University and the Changzhou Sunan Water Environment Research Institute.
The most under-served adjacent branches are G06N (AI-based process control, 3 records), H01G (Capacitors, 5 records), H01M (Batteries and fuel cells, 5 records), and C25B (Electrolytic production, 9 records). These are observations of relative sparsity; technical and commercial viability should be independently validated before treating them as investment targets.
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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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