VRFB Protection & Relaying Patent Landscape 2026
The vanadium redox flow battery protection and relaying space is a growth-stage field with filing activity up significantly over the recent multi-year window, dominated by Chinese state-linked and industrial filers. JD Holdings leads by patent records, but the top five filers hold only a modest share of the hundred largest filers’ combined total, pointing to a fragmented competitive structure with room for new entrants.
Chinese filers dominate a fragmented, growth-stage field
China Three Gorges Corporation and Wuhan NARI (State Grid) each with 4 patent records, and Zhongbei University with 3 patent records. The top tier is composed predominantly of Chinese state-owned enterprises, grid operators, and their affiliated research institutes.
The top five filers account for roughly 20% of the hundred largest filers’ combined total, indicating no single player has achieved lock-in concentration. The gap between the leader and the second tier is narrow — only 2 patent records — confirming a fragmented rather than oligopolistic structure.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | JD Holdings Inc. | 6 | |
| 2 | China Three Gorges Corporation | 4 | |
| 3 | Wuhan NARI Limited (State Grid Electric Power Research Institute) | 4 | |
| 4 | North University of China (Zhongbei University) | 3 | |
| 5 | Shanxi Guorun Energy Storage Technology Co., Ltd. | 3 | |
| 6 | Mitsubishi Electric Corporation | 2 | |
| 7 | Dalian Institute of Chemical Physics, Chinese Academy of Sciences | 2 | |
| 8 | Hubei Zhongfan Energy Storage Technology Co., Ltd. | 2 | |
| 9 | Sichuan Chemical Group Co., Ltd. Chengdu Engineering Branch | 2 | |
| 10 | ThyssenKrupp Industrial Solutions AG | 2 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Wuhan NARI Limited | 2 | |
| 12 | Wuhan University of Technology | 2 | |
| 13 | ZHANGJIAKOU WIND & SOLAR POWER ENERGY DEMONSTRATIO… | 2 | |
| 14 | Atomic Energy Council Institute of Nuclear Energy Research (Taiwan) | 2 | |
| 15 | Hunan Yinfeng New Energy Co., Ltd. | 2 | |
| 16 | VRB Energy Inc. | 2 | |
| 17 | State Grid Electric Power Research Institute | 2 | |
| 18 | ThyssenKrupp AG | 2 | |
| 19 | Wontai Power Co., Ltd. | 2 | |
| 20 | Anhui Conch Ronghua Energy Storage Technology Co., Ltd. | 2 |
The incumbents’ positions imply that early-mover advantage is limited and that well-targeted filings in underserved technical branches could establish a meaningful position without facing an entrenched blocker portfolio.
Filing counts for 2025 and 2026 are understated due to typical patent publication lag of 18–24 months; the apparent plateau in the most recent periods should not be read as a slowdown. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Accelerating filings with heavy concentration in cell-level IP
The two charts below show the annual trajectory of filing activity and the IPC class distribution of the corpus, together revealing both the pace of market entry and where technical effort is being directed.
Annual filing trend
Filings were modest and uneven from 2017 through 2021, then stepped up sharply from 2022 onward, with 2024 and 2025 each recording 12 filings before publication lag suppresses the 2026 count. The 123% recent-window growth rate confirms the field is in an active growth phase; 2025–2026 figures will rise as pending applications publish.
↗ Hover for values · click a bar to ask EurekaTechnology composition
H01M (batteries, cells, and fuel cells) accounts for the large majority of IPC classifications, reflecting a focus on electrochemical cell-level protection. H02J (power supply and grid systems) and H02H (protective circuit arrangements) are the next-largest branches but hold a much smaller share, indicating that grid-integration protection and dedicated protective relay circuitry remain relatively underdeveloped relative to cell-level work.
↗ 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.
All-vanadium redox flow battery system
Provided in the present disclosure is an all-vanadium redox flow battery system. A cathode electrolyte is stored in a cathode electrolyte storage tank of the system, a vanadium cathode active material being added in the cathode electrolyte, an anode electrolyte being stored in an anode electrolyte storage tank, a vanadium anode active material being added… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Efficient energy storage systems using vanadium re… | 114 |
| 2 | Single capacity balancing in a redox flow battery | 27 |
| 3 | 液流电池的电解液温度的控制方法及系统 | 12 |
| 4 | 全钒液流电池储能电站储液罐气体在线控制装置及方法 | 11 |
| 5 | 一种全钒液流电池用管路系统 | 10 |
| 6 | 一种全钒液流电池储能模块装置及其电压均衡控制方法 | 8 |
| 7 | 一种用于全钒液流电池电解液存储装置中的温控装置 | 8 |
| 8 | System for determining bus line accident section | 8 |
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 emerge from the filing data: lifecycle stage, concentration dynamics, collaboration patterns, and geographic coverage. Each has direct implications for where to focus engineering and IP resources.
Growth stage with annual filings still rising
The lifecycle evidence places VRFB protection and relaying firmly in the Growth stage, with annual filings still rising and the most recent years understated by publication lag. Entering now allows a filer to shape emerging standards rather than design around an established portfolio. The 123% multi-year growth rate signals intensifying commercial interest, likely driven by utility-scale VRFB deployments in China.
Growth stageFragmented top tier — no dominant blocker
The top five filers hold 20% of the hundred largest filers’ combined total, and the leader-to-second-tier gap is just 2 patent records. No single applicant has built a blocking position. For a new entrant, the landscape is navigable: targeted filings in protective circuit arrangements or grid-side relaying could establish a defensible cluster without colliding with a large incumbent portfolio.
Low concentrationGrid operator–research-institute pairings dominate co-filing
The most active co-filing pairs are Wuhan NARI (State Grid) with Zhangjiakou Wind & Solar (2 joint filings) and Wuhan NARI with State Grid Jiangsu Research Institute (1 joint filing), both within the State Grid ecosystem. China Three Gorges Corporation co-filed twice with the Dalian Institute of Chemical Physics. ThyssenKrupp AG and ThyssenKrupp Industrial Solutions also filed jointly. Cross-sector or international collaboration is absent from the evidence.
Grid-institute pairsChina-centric filing with limited international coverage
China accounts for 57 of the patent-record-level jurisdiction filings, far ahead of the United States at 7 and Japan at 4. Europe (EPO) has 3 records and WIPO (PCT) has 2, suggesting few filers have pursued broad international coverage. For non-Chinese players, the relatively sparse US and European filing count leaves room to establish jurisdiction-level positions that Chinese incumbents have not yet secured.
China-dominantGo 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 |
|---|---|---|
| Wuhan NARI Limited (State Grid Electric Power Research Institute) | State Grid Jibei Zhangjiakou Wind & Solar Storage & Transmission New Energy Co., Ltd. | 2 |
| China Three Gorges Corporation | Dalian Institute of Chemical Physics, Chinese Academy of Sciences | 2 |
| ThyssenKrupp AG | ThyssenKrupp Industrial Solutions AG | 2 |
| Wuhan NARI Limited (State Grid Electric Power Research Institute) | State Grid Jiangsu Electric Power Co., Ltd. Electric Power Research Institute | 1 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
JD Holdings leads on volume; State Grid affiliates dominate grid-side IP
The top two positions reflect different strategic orientations: JD Holdings concentrates on cell-level battery IP, while State Grid-affiliated entities extend into power supply and protective circuit classes. Both positions are relatively small in absolute terms, reflecting the field’s early-growth fragmentation.
JD Holdings
JD Holdings leads the corpus with 6 patent records, focused tightly on H01M 8 (fuel cell and flow battery systems) with 6 records, plus 2 in H01M 2 (cell component protection). Its applicant momentum data is not separately listed in the recent-entrant trend, suggesting its position predates the most recent growth surge. The portfolio is cell-centric with no evident extension into grid protection or relay circuitry.
6 patent recordsChina Three Gorges Corporation
China Three Gorges Corporation holds 4 patent records and is flagged as a new entrant in the most recent filing window, indicating its engagement in VRFB protection is recent and likely tied to utility-scale storage deployments. Its technology focus spans H01M 8 (3 records), H02H 7 (protective circuit arrangements), and H02J 7 (grid power supply systems), making it the broadest multi-branch filer among the leaders and a natural partner or competitor for grid-integration protection work.
4 patent records| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Shanxi Guorun Energy Storage Technology Co., Ltd. | 4 | ▲ new entrant |
| China Three Gorges Corporation | 3 | ▲ new entrant |
| Hunan Yinfeng New Energy Co., Ltd. | 2 | ▲ new entrant |
| Hubei Zhongfan Energy Storage Technology Co., Ltd. | 1 | ▲ new entrant |
Under-served branches in protective circuits, measurement, and AI-assisted monitoring
Several IPC classes adjacent to the dominant H01M core carry very low filing counts relative to their technical relevance to VRFB protection and relaying. These are observations of relative sparsity; whether they represent actionable opportunities depends on a filer’s existing capabilities and the competitive context in each branch.
H02H · Protective circuit arrangements
With only 6 patent-record-level classifications and a 5% share, dedicated protective circuit IP for VRFB systems is sparse. Given that utility-scale VRFBs require fault isolation, over-voltage protection, and thermal runaway prevention at the power-electronics interface, this branch has plausible technical value. An entry path exists for power-electronics firms or grid-protection specialists who can adapt existing H02H relay and protection expertise to the VRFB electrochemical environment.
Search this in Eureka →G01R · Electric & magnetic measurement for VRFB monitoring
G01R (electric and magnetic measurement) holds only 2 patent-record-level classifications despite being foundational to state-of-charge estimation, capacity fade detection, and impedance diagnostics in flow batteries. The combination of sparse coverage and clear operational need makes this a plausible adjacent area. Instrumentation and sensor companies with existing G01R portfolios could extend into VRFB-specific measurement and monitoring with limited prior-art friction.
Search this in Eureka →How leading filers differ across technology branches
Route coverage across the main technology branches in the current evidence set.
| Player | H01M 8 · Batteries, cells & fuel cells | H02J 7 · Power supply & grid systems | H02H 7 · Protective circuit arrangements | H02J 3 · Power supply & grid systems | B01D 46 · Separation processes (filtration etc.) |
|---|---|---|---|---|---|
| JD Holdings Inc. | Strong · 6 | Absent | Absent | Absent | Absent |
| Wuhan NARI Limited (State Grid Electric Power Research Institute) | Strong · 6 | Absent | Absent | Absent | Absent |
| North University of China (Zhongbei University) | Strong · 3 | Strong · 3 | Absent | Absent | Absent |
| Shanxi Guorun Energy Storage Technology Co., Ltd. | Strong · 4 | Absent | Absent | Absent | Moderate · 1 |
| China Three Gorges Corporation | Strong · 3 | Moderate · 1 | Moderate · 1 | Absent | Absent |
| Hefei University of Technology | Strong · 2 | Moderate · 1 | Absent | Absent | Absent |
| Anhui Conch Ronghua Energy Storage Technology Co., Ltd. | Strong · 2 | Absent | Absent | Absent | Moderate · 1 |
Frequently asked questions
The corpus covers 63 patent families in scope globally. The total reflects filings identified across all jurisdictions; 2025 and 2026 counts are understated due to publication lag.
JD Holdings leads with 6 patent records, ahead of China Three Gorges Corporation and Wuhan NARI (State Grid) at 4 patent records each, and Zhongbei University at 3 patent records.
The lifecycle evidence places the field in the Growth stage. Annual filings are still rising, with a 123% growth rate over the recent window, and the most recent years are understated by publication lag. This is not a mature or declining field.
China leads with 57 patent-record-level jurisdiction filings, followed by the United States at 7, Japan at 4, Europe (EPO) at 3, and WIPO (PCT) at 2. Coverage outside China is limited, leaving room for non-Chinese filers to establish positions in US and European jurisdictions.
H02H (protective circuit arrangements) has only 6 patent-record-level classifications despite being directly relevant to fault isolation and over-voltage protection in VRFB systems. G01R (electric and magnetic measurement) and G06N (AI-based computing models) each have only 2, despite their relevance to state-of-charge monitoring and intelligent fault detection.
Observed co-filing pairs are concentrated within the Chinese State Grid ecosystem: Wuhan NARI filed jointly with Zhangjiakou Wind & Solar (2 joint filings) and with State Grid Jiangsu Research Institute (1 joint filing). China Three Gorges co-filed twice with the Dalian Institute of Chemical Physics. ThyssenKrupp AG and ThyssenKrupp Industrial Solutions also filed jointly. No cross-sector or international collaboration pairs appear in the evidence.
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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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