Sulfide Solid Electrolyte Landscape 2026 — PatSnap Eureka
Sulfide Solid Electrolyte Technology Landscape 2026
27 active patents, 10⁻² S cm⁻¹ ionic conductivity benchmarks, and a heavily concentrated IP thicket — map every composition family, assignee, and white space in the sulfide SSE space with PatSnap Eureka.
What Are Sulfide Solid Electrolytes?
Sulfide solid electrolytes (SSEs) are inorganic ionic conductors built around sulfide anion frameworks — principally Li–P–S and Li–P–S–X (X = halogen) systems — that exhibit ionic conductivities comparable to or exceeding liquid electrolytes while remaining non-flammable. According to WIPO patent data, solid-state battery filings have grown substantially over the past decade, with sulfide chemistries leading the pack.
Academic literature in the dataset confirms that sulfide SSEs exhibit Young's moduli of approximately 20 GPa — significantly softer than oxide electrolytes — enabling room-temperature cold-pressing and slurry-based electrode fabrication, critical for scalable manufacturing. This mechanical compliance is a key differentiator from competing oxide and polymer electrolyte systems tracked on the PatSnap platform.
Key remaining challenges identified across multiple sources include moisture sensitivity and H₂S gas generation, narrow electrochemical windows against high-voltage cathodes, and anode/cathode interface instability. The U.S. Department of Energy has identified solid-state batteries as a priority technology for next-generation vehicle electrification.
Within this dataset, four dominant composition families emerge: argyrodite-type structures (Li₆PS₅X), LGPS-type structures (Li₁₀GeP₂S₁₂ and Ge-free analogues), Li₃PS₄/Li₇P₃S₁₁ glass-ceramic systems, and chalcogenide sodium-ion conductors for sodium all-solid-state batteries. Researchers can explore the full patent analytics landscape for each family via PatSnap.
Assignee Landscape & Ionic Conductivity Benchmarks
All data derived from the 27 active patents and literature records retrieved in this dataset (2013–2026). Analysis powered by PatSnap Eureka.
Active Patents by Assignee (Dataset, 2013–2026)
Mitsui Mining & Smelting leads with 7 patents; top 5 Japanese entities hold 20 of 27 total retrieved patents.
Ionic Conductivity by SSE Composition Family (mS cm⁻¹)
Na-ion sulfide conductor Na₂.₈₈Sb₀.₈₈W₀.₁₂S₄ achieves 32 mS cm⁻¹ — the highest in this dataset. LGPS exceeds 10 mS cm⁻¹.
Four Key Innovation Clusters in Sulfide SSE Patents
The 27 active patents retrieved group into four distinct technical approaches, each representing a different strategy for achieving high conductivity and commercial viability.
Halogen-Doped Argyrodite Compositions (Li₆PS₅X)
The dominant patent cluster, accounting for at least 12 of the 27 active patents retrieved. The core mechanism relies on substituting sulfur sites in the argyrodite framework with halogen anions (Cl, Br, I, F), creating lithium vacancies or interstitials that enhance Li⁺ hopping through the cubic F-4̄3m crystal structure. Ionic conductivities of 1–5 mS cm⁻¹ are routinely reported. The most active assignees are Mitsui Mining & Smelting and Idemitsu Kosan, whose combined EP filings span 2019–2026 and define the commercial baseline.
12 / 27 active patentsLGPS-Type and Ge-Free Thio-LISICON Structures
The Li₁₀GeP₂S₁₂ (LGPS) class achieves the highest bulk conductivities (>10 mS cm⁻¹) but faces challenges from costly germanium content and reduction instability against lithium metal. Tokyo Institute of Technology's patent sub-cluster focuses on Ge-free analogues using Si, Sn, or Sn–Si solid solutions — specifically Li₄₋₄z₋ₓ[SnySi₁₋y]₁₊z₋ₓPₓS₄ compositions confirmed by XRD at 2θ = 29.58° without the competing 27.33° phase, demonstrating electrochemical stability without Ge. Tokyo Tech holds 3 EP patents in this sub-cluster alone.
>10 mS cm⁻¹ conductivityNitrogen and Multi-Element Doped Crystalline Sulfide SSEs
A distinct cluster from GS Yuasa International targets nitrogen co-doping of sulfide frameworks alongside aliovalent metal dopants (Al, Si, B, Mg, Zr, Ti, Hf, and others). This approach modifies the crystal phase distribution (targeting Li₇P₃S₁₁, Li₄P₂S₆, or β-Li₃PS₄ phases) and appears aimed at simultaneously improving conductivity and thermal/electrochemical stability. GS Yuasa's three EP filings (2025) are characterized by XRD signatures at 2θ = 17.9°, 19.1°, 29.1°, 29.8° — and extend to Al+N co-doped variants and Li/Na/K alkali variants with Cl/Br/I halogen combinations.
3 EP patents · GS Yuasa 2025Moisture Stabilization via Surface Engineering
A cross-cutting cluster addresses the critical commercialization barrier of atmospheric instability. Strategies include core-shell particle design, surface coatings, and oxysulfide nanolayers, and controlled oxygen/sulfur surface gradients. Korea Institute of Science and Technology (KIST, 2020) demonstrated air-stable oxysulfide nanolayer-coated SSEs retaining 82.8% of initial conductivity after combined air and slurry chemical exposure. Toyota Motor Corporation engineered the oxygen/sulfur ratio at particle surface (XPS O/S = 0.79–1.25) vs. 30 nm depth (O/S ≤ 0.58) to reduce resistance increase after cycling.
6+ patents · key commercial barrierThree Phases of Sulfide SSE Development (2013–2026)
Top Patent Holders in Sulfide Solid Electrolytes
Japan dominates the active patent subset. Five Japanese entities account for 20 of 27 retrieved active patents. Korean and US players are present primarily in literature rather than the patent subset.
| Assignee | Active Patents Retrieved | Jurisdictions | Primary Technology Focus |
|---|---|---|---|
| Mitsui Mining & Smelting Co., Ltd. | 7 | EP | Halogen-doped argyrodite; moisture stabilization; Al-doping; H₂S suppression |
| Idemitsu Kosan Co., Ltd. | 4 | EP | Li–P–S–Cl–Br argyrodite; Cl/P and Br/P molar ratio control; XRD peak area ratio |
| GS Yuasa International Ltd. | 3 | EP | N-doped and multi-element crystalline SSEs; Al+N co-doping; XRD-characterized phases |
| Toyota Motor Corporation | 3 | JP | Argyrodite phase purity via ³¹P-NMR; particle engineering; composite SSEs for automotive |
| Tokyo Institute of Technology | 3 | EP | Ge-free LGPS analogues; Sn–Si solid solutions; water-resistance via Ge²⁺ surface control |
Monitor Competitor SSE Filings in Real Time
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What the IP Landscape Means for R&D Strategy
Five strategic signals derived from the patent and literature dataset. All claims traceable to retrieved records.
Dense IP Thicket in Argyrodite Space
IP landscape is heavily concentrated in Japanese industry. Mitsui Mining & Smelting and Idemitsu Kosan together hold more than 40% of the active patents retrieved and are filing actively through 2026. Any market entrant in argyrodite-type SSEs faces a dense IP thicket requiring either licensing or design-around using alternative compositions such as telluride-substituted or Ge-free LGPS analogues.
Moisture Stability Is the Commercial Bottleneck
The field has achieved sufficient bulk ionic conductivity (>1 mS cm⁻¹) in multiple composition families. The current patent race — reflected in at least 6 of the 27 active patents — centers on suppressing H₂S gas generation and maintaining conductivity after dry-room or slurry-process exposure. Oxysulfide compositions and surface-engineered core-shell particles are the two leading strategies.
Where Sulfide SSE Technology Is Being Deployed
Three primary application domains emerge from the patent and literature dataset: automotive, consumer electronics, and grid-scale energy storage.
Patent Filing Activity by Phase (Dataset Records)
10 records dated 2024–2026 signal a commercialization-focused phase, up from 3 foundational records (2013–2018).
Application Domain Distribution (Patent Motivation Statements)
Automotive is the primary stated application across the majority of patent filings; all 7 Toyota patents explicitly cite automotive power sources.
Sulfide Solid Electrolyte Technology — Key Questions Answered
Sulfide solid electrolytes achieve room-temperature ionic conductivities reaching 10⁻² S cm⁻¹ (10 mS cm⁻¹) in optimized compositions, making them comparable to or exceeding liquid electrolytes. The Na₂.₈₈Sb₀.₈₈W₀.₁₂S₄ sodium conductor reported by Osaka Prefecture University achieves 32 mS cm⁻¹ — the highest reported room-temperature conductivity in this dataset for any solid electrolyte.
Within this dataset, Mitsui Mining & Smelting Co., Ltd. leads with 7 active patents retrieved (all EP jurisdiction), followed by Idemitsu Kosan Co., Ltd. with 4 EP patents. Together these two companies account for more than 40% of the 27 active patents retrieved. GS Yuasa International Ltd. and Toyota Motor Corporation each hold 3 patents, and Tokyo Institute of Technology holds 3 EP patents.
Moisture stability is the defining commercial barrier, not bulk conductivity. The field has achieved sufficient bulk ionic conductivity (greater than 1 mS cm⁻¹) in multiple composition families. The current patent race — reflected in at least 6 of the 27 active patents in this dataset — centers on suppressing H₂S gas generation and maintaining conductivity after dry-room or slurry-process exposure. Oxysulfide compositions and surface-engineered core-shell particles are the two leading strategies.
Halogen-doped argyrodite compositions (Li₆PS₅X / Li₇₋ₓPS₆₋ₓXₓ) form the dominant patent cluster, accounting for at least 12 of the 27 active patents retrieved. The core mechanism relies on substituting sulfur sites in the argyrodite framework with halogen anions (Cl, Br, I, F), which creates lithium vacancies or interstitials that enhance Li⁺ hopping. Ionic conductivities of 1–5 mS cm⁻¹ are routinely reported. The most active assignees are Mitsui Mining & Smelting and Idemitsu Kosan.
Telluride-substituted argyrodites represent a white space opportunity. JX Nippon Mining & Metals appears to be the primary filer in Li₈MeS₅Te/Li₈SiS₆Te space with only 2 filings (2024–2025). This composition family is underexplored relative to chloride/bromide argyrodites and may offer differentiated IP positions for challengers, subject to freedom-to-operate analysis. Oxysulfide solid electrolytes for moisture resistance (filed by Korea Electronics Technology Institute, JP 2024) are also an emerging design paradigm.
Sulfide solid electrolytes exhibit Young's moduli of approximately 20 GPa — significantly softer than oxide electrolytes — enabling room-temperature cold-pressing and slurry-based electrode fabrication, critical for scalable manufacturing. Combined with their high ionic conductivity (up to 10⁻² S cm⁻¹), non-flammability, and compatibility with existing battery manufacturing processes, they are widely regarded as the most commercially viable pathway to solid-state batteries for electric vehicles and large-scale energy storage.
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References
- Sulfide solid electrolyte and all-solid-state battery — GS Yuasa International Ltd., 2025, EP
- Sulfide solid electrolyte and all-solid-state battery — GS Yuasa International Ltd., 2025, EP
- Sulfide solid electrolyte and all-solid-state battery — GS Yuasa International Ltd., 2025, EP
- Sulfide solid electrolyte and battery — Mitsui Mining & Smelting Co., Ltd., 2022, EP
- Sulfide solid electrolyte — Mitsui Mining & Smelting Co., Ltd., 2026, EP
- Solid electrolyte, electrode mix, solid electrolyte layer, and all-solid-state battery — Mitsui Mining & Smelting Co., Ltd., 2024, EP
- Sulfide-based solid electrolyte for lithium secondary battery — Mitsui Mining and Smelting Co., Ltd., 2021, EP
- Sulfide solid electrolyte — Idemitsu Kosan Co., Ltd., 2021, EP
- Sulfide solid electrolyte — Tokyo Institute of Technology, 2024, EP
- Sulfide solid electrolyte — Tokyo Institute of Technology, 2021, EP
- Sulfide solid electrolyte, all solid state battery, and method for producing sulfide solid electrolyte — Tokyo Institute of Technology, 2024, EP
- Sulfide solid electrolyte, precursor of sulfide solid electrolyte, all solid state battery and method for producing sulfide solid electrolyte — Toyota Motor Corporation, 2025, EP
- Sulfide solid electrolyte particles and all-solid-state batteries — Toyota Motor Corporation, 2022, JP
- Composite solid electrolyte and all-solid-state battery — Toyota Motor Corporation, 2022, JP
- Sulfide-based solid electrolyte and all-solid-state lithium ion battery — JX Nippon Mining & Metals Corporation, 2025, EP
- Sulfide-based solid electrolytes and all-solid-state lithium-ion batteries — JX Metals Corporation, 2025, JP
- Solid electrolyte and all-solid-state battery containing the same — Korea Electronics Technology Institute, 2024, JP
- Sulfide solid electrolyte for all-solid-state secondary battery — Industry-Academia Cooperation Group of Sejong University, 2023, EP
- A sodium-ion sulfide solid electrolyte with unprecedented conductivity at room temperature — Osaka Prefecture University, 2019
- High-Performance All-Solid-State Lithium–Sulfur Batteries Enabled by Slurry-Coated Li₆PS₅Cl/S/C Composite Electrodes — Zhejiang University of Technology, 2021
- WIPO — World Intellectual Property Organization (global patent filing statistics)
- European Patent Office (EPO) — EP filing jurisdiction data
- U.S. Department of Energy — Solid-State Battery R&D Program
All data and statistics on this page are sourced from the references above and from PatSnap's proprietary innovation intelligence platform. This landscape is derived from a limited set of patent and literature records retrieved across targeted searches and represents a snapshot of innovation signals within this dataset only.
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