Integrated all-solid-state battery cell stack — ordered multilayer with endpoint qualification

The integrated all-solid-state battery cell stack is a platform-level system claim that combines, in a single ordered article, an anode-side oxide interlayer, a buffered halide/sulfide separator, and a cation-ordered Li2MgMn3O8 cathode — qualified not by any single composition but by measured cell performance (critical current density at or above 0.8 mA/cm2, interfacial resistance at or below 30 ohm-cm2, and capacity retention at or above 80% after 200 cycles). Its strategic significance is architectural: rather than claiming a point fix at one interface, it claims the finished article — the whole cooperating stack — and defines it by what the article must do. The why-now is the converging ASSB commercialization race. Oxide, halide, and sulfide programs are independently approaching full-cell demonstrations, but none has secured IP on the integration itself. An architecture patent that ties all three layer families together by measured cell behavior becomes the position that competitors must license or design around as they assemble full cells. Within the broader solid-state battery electrolytes and interfaces portfolio, this asset functions as a capstone: the family-level assets protect individual layers, and this claim covers the assembled, endpoint-qualified stack above them. That layered structure means an infringer who redesigns one component still reads on the system claim if the article meets the recited endpoints.

Each candidate is validated by multiple independent machine-learning interatomic potentials. A material advances only when the engines agree on phonon (dynamic) stability — disagreement is surfaced, not hidden.

The cell architecture is an ordered multilayer: cathode / cathode-side solid electrolyte / buffer / garnet-or-sulfide separator / anode-side oxide interlayer / Li- or Na-metal anode. Each interface position addresses a specific, well-documented failure mode. The anode-side oxide interlayer stabilizes the lithium-metal/garnet contact, where direct contact causes microstructural degradation and void formation under cycling. The buffer layer between the halide and sulfide electrolyte phases suppresses interdiffusion that would otherwise generate high-resistance interphase products. The cation-ordered Li2MgMn3O8 cathode (P4_332 space group) presents an all-Mn4+ high-voltage surface with suppressed oxygen evolution — a known failure mode for disordered Mn-rich oxides that limits cathode-side electrolyte compatibility. Computational validation was carried out in two complementary modes. At the constituent level, two independent machine-learning interatomic potentials — MACE and CHGNet — were applied independently to screen the component materials. Both returned dynamically stable verdicts, meaning neither found imaginary phonon modes, and agreement between two unrelated ML potential frameworks materially strengthens confidence that the stability finding is not an artifact of one model's training set. A reaction-compatibility screen assessed thermodynamic compatibility across all layer pairings, identifying which contact configurations are stable against chemical reaction under operating conditions. A separate explicit-interface molecular dynamics simulation using the MACE potential modeled the full trilayer stack against an unprotected control, directly quantifying interdiffusion suppression in the buffered halide/sulfide interface — the most chemically active junction in the stack. The cell endpoint set (CCD, interfacial resistance, capacity retention) is the intended measured property; it is defined at the system level rather than as a single material constant, which is appropriate for a stack in which performance emerges from the cooperation of all layers.

The addressable market for integrated ASSB technology is estimated at over $10 billion across electric vehicle traction, grid-scale stationary storage, and premium consumer electronics. This is an estimate, not an audited figure, but the order of magnitude is consistent with the scale of EV OEM capital commitments and announced cell production targets for solid-state platforms through the early 2030s. The architecture claim spans the whole cell rather than a single layer, which means value accrues wherever a qualifying full cell is manufactured — not only at the electrolyte supplier or the cathode maker, but at any entity assembling the integrated article. The natural royalty structure for a system claim of this type is a running per-cell rate applied at the finished-article level. Because the claim reads on the assembled stack rather than a component, it cannot be exhausted at the material supply stage; it attaches to the cell manufacturer. A low single-digit royalty on qualifying full cells, applied across the EV and grid customer bases, generates a commercially meaningful revenue stream at scale even on modest market-penetration assumptions. Buyers are EV OEMs integrating ASSB packs, cell manufacturers supplying them, and grid integrators deploying stationary storage — each of whom would incur this royalty on every cell that meets the recited endpoints. The caveat that matters commercially is that no integrated full-cell test vehicle has been built against the claimed endpoints yet. Until that coupon exists, the claim is supported by computational evidence and individual-layer demonstrations rather than a measured full-cell result. This limits near-term enforceability and affects valuation: a buyer must price in the cost and risk of building the first integrated coupon. That experiment is, however, well-scoped and technically tractable given the existing layer-level data — it is a known next step, not an open research question.

only integrated architecture addressing every internal-interface failure mode in one ordered, endpoint-qualified stack

claimed by ordered configuration + cooperating-layer endpoint limitations

The natural acquirers are EV OEMs and large-format cell manufacturers that are building or sourcing integrated ASSB cells for traction applications, and grid integrators deploying stationary storage at scale. For an OEM or tier-one cell maker, outright acquisition is strategically coherent: the claim reads on the finished article and confers freedom to assemble any compatible layer chemistry into the ordered stack, making it platform IP that underlies a product line rather than a component license. An exclusive license to a single player in each major application segment — automotive, grid — would achieve a similar competitive effect while preserving flexibility for the current owner. For materials and coating suppliers, a field-of-use license tied to specific layer positions (interlayer material, buffer, cathode) is the appropriate structure, since these entities sell into the stack rather than own the finished cell. Given the estimated addressable market and the architecture breadth of the claim, this asset commands acquire-or-exclusive-license treatment for any serious ASSB program; a non-exclusive license would dilute the architecture monopoly that makes the claim commercially significant in the first place.

The primary risk is proof maturity. The claimed cell endpoints have not been measured on an integrated full-cell coupon, which means the claim is currently prophetic with respect to its performance limitations. This lowers near-term enforceability and requires a buyer to underwrite the cost and schedule of building the first test vehicle. System claims defined by performance over a broad layer genus also face heightened written-description and enablement scrutiny during prosecution and litigation; the endpoints must be demonstrated across representative chemistries — not a single example — to support the full scope of the genus. There is also execution risk that the integrated stack underperforms its individually validated layers, because compounded interfaces can generate emergent resistance or degradation not captured by layer-level screening. The de-risking roadmap is well-defined and narrows to one priority: build the integrated full-cell test vehicle and measure CCD, interfacial resistance, and capacity retention against the claimed thresholds. A second test using at least one alternate interlayer chemistry and one alternate separator would begin to establish genus breadth and address the enablement risk. Timing matters — the ASSB commercialization race means that priority and demonstrated reduction to practice carry increasing weight as more players approach full-cell demonstrations, making execution speed as strategically important as technical outcome.