QuantumScape opens Osprey platform to sulphide solid-state developers

QuantumScape has clocked 1,000 full charge cycles with roughly 80% capacity retention and a 10-to-80% fast charge in five minutes on its new 'Osprey' cells — the headline numbers behind the US solid-state developer's decision to open a collaborative platform for sulphide-based battery makers.

The platform, announced under the name Osprey, builds on QuantumScape's existing QSE architecture. It pairs the ceramic separator the San Jose company has developed over recent years with its anode-free lithium-metal design (a cell that draws all its lithium from the cathode, dispensing with a conventional anode). The stated aim: enable new licensing and co-development options for current customers and extend the offering to developers of sulphide-based all-solid-state batteries.

Why target sulphides?

The battery industry has worked on sulphide electrolytes for years without a commercially viable result. QuantumScape's own whitepaper is blunt about the appeal and the problem: "Sulfide-based solid-state battery approaches are widely popular across the battery industry. Their popularity is due to the high ionic conductivity of sulfide electrolytes and the relative simplicity of processing them. However, sulfides still face several significant limitations, including the need for high applied pressure, as well as poor cycle life and incompatibility with lithium metal."

Progress along the value chain has been real but fragmented, the company says, and every effort "has run against the same fundamental limitations of sulphides as separators." Osprey is positioned as the fix: customers can keep their own cathode technology, materials and supply chain while adopting the QuantumScape ceramic separator, or use the company's proprietary sulphide-based cathode.

The test conditions matter for practitioners. QuantumScape reports the results were achieved at 1C/1C charge and discharge rates, cathode loading above 5 mAh/cm², 100% depth of discharge at room temperature — all at just 1 atmosphere of applied pressure, the parameter that has plagued sulphide designs. High-loading cathodes push cell-level energy density to roughly 1,100 Wh/L. Compatibility has been demonstrated with both QuantumScape's own solid cathodes and third-party versions.

What does this change for cell developers?

It converts QuantumScape from a full-stack supplier into a component and platform licensor for a second chemistry family. CEO Dr Siva Sivaram framed the bet: "The industry has invested heavily in sulphide-based batteries but keeps hitting the same fundamental limits. As the data shows, Osprey can address these limitations. We believe Osprey can unlock the full potential of all-solid-state batteries, and our goal is to make it the leading platform for solid-state battery development." Automotive partners are already working on development projects based on the platform, starting in the early stages of cell development.

The caveats are explicit. The results come primarily from two-layer test cells with the same footprint as the QSE-5 design. Automotive customers generally want larger prismatic cells, and QuantumScape concedes that "larger cells will likely require both more layers and more area per layer." The process has been demonstrated only at laboratory scale, leaving substantial work on production engineering.

The QSE-5 track record

Osprey sits alongside, not instead of, the QSE-5 — the 5 Ah, 84.5 x 65.6 x 4.6 mm cell that remains QuantumScape's first commercial product, with energy density above 844 Wh/L, a 12.2-minute 10-to-80% charge and operation down to -30°C. The timeline so far:

• A0 samples delivered to automakers in December 2022
• "Alpha-2" cells in March 2024
• Small-scale B-sample production and delivery announced October 2024
• B1 sample deliveries reported October 2025; Volkswagen is a likely recipient
• Key equipment for QSE-5 pilot production installed in San Jose late 2025
• The automated Eagle Line pilot inaugurated February 2026

Volkswagen, QuantumScape's principal backer, deepened ties in summer 2025; the joint programme centres on the solid-state Ducati V21L motorcycle. Honda has been publicly listed as a development partner since mid-2025. QuantumScape does not plan to mass-produce cells itself — GWh-scale output is intended to come through licensing partners.

Watch for the first named Osprey development partner, multi-layer cell data at scale, and any sign that laboratory pressure results hold on the Eagle Line.