EnergyIntelligence

QuantumScape Osprey tackles the pressure problem in solid state batteries

Laboratory cells retained about 80 percent capacity after 1000 cycles under modest compression

Published November 12, 2026Intelligence / Energy / Advanced Battery Tech

QuantumScape has reported a solid-state battery result that addresses a stubborn obstacle to putting more energy into an electric car: the clamping hardware needed to hold its layers together. Its new Osprey platform completed 1,000 full charge-discharge cycles with about 80 percent capacity remaining under one atmosphere of applied pressure, the company announced November 11. [1]

Pressure helps the solid materials inside a battery maintain contact as they expand and contract. Heavy clamping equipment takes up space and adds weight, reducing the benefit of an energy-dense cell. Osprey combines QuantumScape’s ceramic separator with a solid, sulfide-based material inside the positive electrode, or cathode. The company says automotive partners are already helping develop the platform, including by contributing their own cathode technology. [1, 2]

In a conventional lithium-ion battery, charged lithium particles move between the electrodes through an electrolyte. A graphite-based negative electrode provides a structure for storing lithium. QuantumScape’s design removes that host: lithium metal forms during charging against the ceramic separator. The separator lets lithium ions pass while keeping the electrodes apart and resisting metal filaments that could cause a short circuit. Osprey retains this barrier and replaces the liquid electrolyte used on the cathode side of QuantumScape’s existing QSE platform with a sulfide-based solid. The two materials perform different jobs within the cell. [2]

The cycle-life result came from a two-layer cell tested at 30°C, with a 50-by-65-millimeter cathode on each layer and a loading of 5.5 milliamp-hours per square centimeter, a measure of capacity per electrode area. It cycled across the full charge range at a nominal one-hour rate, called 1C. The one atmosphere, about 0.10 megapascals, describes externally applied compression on the stack. A separate two-layer test charged from 10 to 80 percent in 4.8 minutes at 80°C, using a 10C charging rate, ten times the nominal one-hour current, and 5.9 mAh/cm² loading. Heating time, energy use and repeated fast-charge durability will shape how that laboratory interval translates to a driver’s experience. [3, 4]

Cold-weather testing used a smaller, single-layer cell with a 21-by-21-millimeter cathode. At −20°C it delivered 68 percent of its 25°C capacity and about 52 percent of its energy using 0.33C pulsed discharge. Capacity measures charge delivered; energy also accounts for voltage. The fast-charge result and projected density of roughly 1,100 watt-hours per liter concern power-optimized and energy-optimized designs, respectively. QuantumScape previously measured 844 Wh/L in a packaged QSE-5 sample at 25°C and a five-hour discharge rate, with charged-cell volume measured under module pressure and the tabbing area excluded. The Osprey projection is about 30 percent higher; comparable measurements from a finished cell will establish the achieved gain. [2, 5, 6]

Independent researchers are pursuing other low-pressure designs. A November 7 Nature Communications paper from a team led at Pohang University of Science and Technology (POSTECH) combined a modified sulfide electrolyte with a porous carbon current collector that provides room for lithium deposition and relieves local stress. The researchers reported room-temperature cycling at 0.3 megapascals or less, a cathode loading of 2.4 mAh/cm² and a slower 0.1C rate. Pressure, loading, charging rate and cell size all affect how demanding a test is; matching those conditions makes comparisons more informative. [7]

For electric aircraft, developers will also need energy per kilogram and power during demanding flight phases. A National Aeronautics and Space Administration (NASA) study shows how cooling, structure and safety provisions change the performance available when cells are assembled into an aircraft battery pack. Those requirements broaden the engineering test beyond energy per liter. [8]

“The industry has invested heavily in sulfide-based batteries but keeps hitting the same fundamental limits,” QuantumScape chief executive Siva Sivaram said. Osprey offers manufacturers a way to retain their work on sulfide cathodes while considering QuantumScape’s separator and integration process, creating possible licensing and development relationships. The platform remains a longer-term research program. Separately, QuantumScape and equipment partner Muehlbauer are working toward a planned 100-megawatt-hour production line with a 2028 start target. Larger Osprey cells, sustained performance through repeated use and consistent manufacturing will determine whether the new platform reaches vehicles. [1, 9]