Li-Ion SEI Interphase Patent Landscape 2026
Sila Nanotechnologies commands the largest single position in this 476-family corpus, with the top five filers accounting for 28% of the hundred largest filers’ combined total — a moderately concentrated field. Activity has expanded strongly on a multi-year basis, though annual volume eased from its 2022 peak and recent years carry publication lag.
Sila Nanotechnologies leads a moderately concentrated field with clear tier gaps
Sila Nanotechnologies holds the top position with 61 patent families, nearly double the next-ranked filer. Contemporary Amperex Technology (Hong Kong) Limited follows at 31 families, with Robert Bosch at 21 and Contemporary Amperex Technology Co. Ltd. at 19.
The top five filers collectively account for 28% of the hundred largest filers’ combined total, indicating moderate concentration. A visible tier gap separates Sila from the pack, while the mid-tier — Zhuhai CosMX Battery, Nexeon, Renault, and Ningde Amperex — clusters between 14 and 18 families.
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 1 | Sila Nanotechnologies Inc. | 61 | |
| 2 | Contemporary Amperex Technology (Hong Kong) Limited | 31 | |
| 3 | Robert Bosch GmbH | 21 | |
| 4 | Contemporary Amperex Technology Co., Ltd. | 19 | |
| 5 | Zhuhai CosMX Battery Co., Ltd. | 18 | |
| 6 | Nexeon Ltd. | 15 | |
| 7 | Renault SA | 14 | |
| 8 | Ningde Amperex Technology Ltd. | 14 | |
| 9 | A123 Systems LLC | 10 | |
| 10 | Anteo Energy Tech Pty Ltd. | 10 |
| # | Applicant | Patent families | Share |
|---|---|---|---|
| 11 | Elkem ASA | 10 | |
| 12 | Toyota Motor Corporation | 8 | |
| 13 | Georgia Tech Research Corporation | 8 | |
| 14 | COUNCIL OF SCI & IND RES | 8 | |
| 15 | Zhejiang Liwinon Energy Technology Co., Ltd. | 7 | |
| 16 | Tyfast | 7 | |
| 17 | Blue Current Inc. | 7 | |
| 18 | M2Innovations LLC | 7 | |
| 19 | Enevate Corporation | 7 | |
| 20 | Senior Material (Europe) AB | 7 |
Sila’s dominant position reflects a focused, startup-scale strategy built around silicon-dominant anode chemistries requiring deliberate SEI engineering, while automotive OEMs (Renault, Bosch) and cell manufacturers (CATL entities, CosMX) defend positions as integrators rather than materials specialists.
Filings in the most recent 18–24 months are likely under-counted due to standard patent publication lag; apparent softness in 2024–2026 data should not be read as a genuine deceleration. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Multi-year growth with a 2022 peak; H01M dominates but adjacent branches are sparse
Two views capture the field’s momentum and technical scope: an annual filing trend that reveals a multi-year growth arc, and an IPC branch breakdown that shows how tightly activity clusters around battery-cell classification.
Annual filing trend
Filings grew from 23 families in 2017 to peaks of 82 in both 2022 and 2023, reflecting a 48% expansion in the recent three-year window versus the prior one. Annual volume has since eased from that 2022 peak; figures for 2024–2026 are further depressed by publication lag and should not be interpreted as a structural decline.
↗ Hover for values · click a bar to ask EurekaTechnology composition
H01M (batteries, cells, and fuel cells) accounts for the overwhelming majority of IPC records, confirming that SEI/interphase work is filed predominantly as cell-level invention. Adjacent branches — C01B (inorganic compounds), C01G (metal compounds), B82Y (nanotechnology), C23C (coatings), and G01R (electrical measurement) — each represent only 2–4% of records, signaling that materials-synthesis and deposition-process routes remain relatively sparse.
↗ 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.
Artificial Solid Electrolyte Interphase For Enabli…
A method for forming an electrochemical device may comprise the steps of: (a) exposing electrode material particles to a lithium-containing precursor followed by an oxygen-containing precursor to form a coating on the electrode material particles; (b) forming a slurry comprising the coated electrode material particles; (c) casting the slurry to form a… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Materials for solid state electrolytes and protect… | 399 |
| 2 | Cathode Additives to Provide an Excess Lithium Sou… | 125 |
| 3 | Electrode for power storage device, power storage … | 78 |
| 4 | Liquid-infiltrated solid-state electrolyte and rec… | 55 |
| 5 | Electrode with conductive interlayer and method th… | 55 |
| 6 | Anode electrode composition of li-ion battery cell | 52 |
| 7 | Lithium fluoride-based and related cathode composi… | 48 |
| 8 | 一种硅基负极锂离子电池及其制造方法 | 42 |
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
The landscape’s maturity stage, concentration pattern, collaborative signals, and geographic coverage together define where incumbents are entrenched and where entry remains feasible.
Growth stage with annual volume easing from a 2022 peak
The field sits in a Growth lifecycle stage: the recent three-year filing window is 48% above the prior period, confirming multi-year expansion. However, annual volume has eased from the 2022 peak, so the technology is past its steepest acceleration phase. New entrants still have a viable window before the field reaches maturity-level consolidation.
Growth · post-peakModerate concentration with a clear leader gap
The top five filers hold 28% of the hundred largest filers’ combined total — moderate, not extreme. Sila Nanotechnologies’ 61-family lead over its nearest rival (31 families) creates a meaningful moat in silicon-anode SEI. Mid-tier players cluster closely, suggesting the 2nd-through-10th positions remain contestable through targeted portfolio building.
Moderate concentrationCo-filing is rare; Renault–Nissan and Sila’s two partnerships are the main signals
Renault and Nissan co-filed on 2 families, reflecting their longstanding alliance’s battery development work. Sila Nanotechnologies co-filed once each with Battelle Memorial Institute and Georgia Tech Research Corporation, indicating selective engagement with national-lab and university expertise. Overall co-filing density is low, suggesting the field is still primarily driven by proprietary, single-assignee IP strategies.
Low co-filing densityUS-centric protection with meaningful EPO and PCT coverage
The United States is the primary filing jurisdiction, followed by Europe (EPO) and WIPO (PCT). India ranks fourth, reflecting growing domestic cell-manufacturing ambition. China shows comparatively modest coverage for a major battery-producing country, and Japan is similarly light — suggesting either strategic gaps or parallel domestic filings outside this corpus.
US-EPO-PCT 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 |
|---|---|---|
| Renault SA | Nissan Motor Co., Ltd. | 2 |
| Sila Nanotechnologies Inc. | Battelle Memorial Institute | 1 |
| Sila Nanotechnologies Inc. | Georgia Tech Research Corporation | 1 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Sila Nanotechnologies leads on volume; CATL entities show divergent momentum
The top filers split between a focused materials specialist (Sila) and large cell/systems manufacturers whose SEI portfolios reflect broader battery programs. Momentum signals vary sharply across the tier.
Sila Nanotechnologies Inc.
Sila Nanotechnologies holds 61 patent families — the largest position in the corpus — concentrated almost entirely in H01M 10 (battery systems) and H01M 4 (electrode materials), consistent with its silicon-dominant anode program where SEI formation is a core design challenge. Momentum is strongly positive at +89% in recent filings versus the prior period, indicating an accelerating IP build rather than a plateau.
families: 61Contemporary Amperex Technology (Hong Kong) Limited
With 31 patent families and a technology focus spanning H01M 10 and H01M 4, this entity represents the CATL group’s international IP arm for SEI-related cell innovation. Its sister entity, Contemporary Amperex Technology Co. Ltd. (19 families), shows a contrasting –50% momentum trend, suggesting the group may be consolidating filings through the Hong Kong route. Together the two CATL entities represent the largest combined cell-manufacturer presence in the corpus.
families: 31| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Sila Nanotechnologies Inc. | 34 | ▲ +89% |
| Contemporary Amperex Technology Co., Ltd. (CATL) | 13 | ▼ -50% |
| Zhuhai CosMX Battery Co., Ltd. | 6 | ▼ -40% |
| Applied Materials Inc. | 6 | ▲ new entrant |
| Ningde Amperex Technology Ltd. | 8 | ▲ new entrant |
| Anteo Energy Tech Pty Ltd. | 10 | ▲ new entrant |
Under-served branches: coatings, nanotechnology, and electrochemical measurement
Several IPC branches adjacent to the dominant H01M class are sparsely populated relative to their technical relevance to SEI engineering. These represent observed gaps, and entry feasibility depends on specific commercial context.
C23C · Coating and surface deposition
With only 13 IPC records, surface-deposition techniques (ALD, CVD, PVD) for artificial SEI layer formation are an under-served branch. Controlled thin-film coatings on anode particles are a plausible route to deterministic SEI composition — a technically adjacent approach that Bosch has begun exploring (C23C16 appears in its focus codes). An entrant with deposition-process expertise could differentiate on process IP rather than material composition alone.
Search this in Eureka →G01R · Electric and magnetic measurement
Only 12 IPC records cover electrical and magnetic measurement techniques in this corpus, despite the fact that in-situ and operando characterization of SEI formation is a recognized analytical bottleneck. IP covering measurement methods for SEI impedance, thickness, or composition is sparse, which may reflect a gap between academic characterization tools and commercial patent strategies. A diagnostics or instrumentation specialist entering this space would face limited incumbent IP in G01R.
Search this in Eureka →How leading filers differ by technology route
Route coverage across the main technology branches in the current evidence set.
| Player | H01M 10 · Batteries, cells & fuel cells | H01M 4 · Batteries, cells & fuel cells | H01M 50 · Batteries, cells & fuel cells | C01B 33 · Non-metallic elements & inorganic compounds | H01M 2 · Batteries, cells & fuel cells |
|---|---|---|---|---|---|
| Sila Nanotechnologies Inc. | Strong · 59 | Strong · 50 | Emerging · 8 | Absent | Emerging · 3 |
| Contemporary Amperex Technology Co., Ltd. (CATL) | Strong · 39 | Strong · 32 | Moderate · 10 | Absent | Absent |
| Renault SA | Strong · 20 | Strong · 16 | Emerging · 4 | Absent | Absent |
| Zhuhai CosMX Battery Co., Ltd. | Strong · 18 | Strong · 16 | Absent | Absent | Absent |
| Robert Bosch GmbH | Strong · 17 | Strong · 11 | Absent | Absent | Moderate · 4 |
| Nexeon Ltd. | Strong · 9 | Strong · 15 | Absent | Moderate · 5 | Absent |
| Applied Materials Inc. | Strong · 14 | Strong · 14 | Absent | Absent | Absent |
Frequently asked questions
The analysis covers 476 patent families. This is the foundational count for all applicant rankings and trend data discussed in this report.
Sila Nanotechnologies Inc. leads with 61 patent families, nearly double the next-ranked filer. Its portfolio is concentrated in battery-system and electrode-material classifications, consistent with its silicon-anode focus.
The field is in a Growth stage. Recent three-year filings are 48% above the prior three-year window. Annual volume has eased from a 2022 peak, but the multi-year trajectory remains expansionary. Recent years’ apparent softness partly reflects standard patent publication lag.
The United States is the primary jurisdiction, followed by Europe (EPO) and WIPO (PCT). India ranks fourth. China and Japan show comparatively lighter coverage within this corpus.
Co-filing is infrequent. The most active collaboration is between Renault and Nissan (2 co-filed families). Sila Nanotechnologies has co-filed once each with Battelle Memorial Institute and Georgia Tech Research Corporation. The overall low co-filing density reflects a predominantly proprietary IP strategy across the field.
C23C (coating and surface deposition), G01R (electrical and magnetic measurement), B82Y (nanotechnology applications), C01B (non-metallic elements and inorganic compounds), and C01G (compounds of other metals) each represent only 2–4% of IPC records, making them the most sparsely filed adjacent branches in the corpus.
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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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