Amprius Technologies, Inc. announced it has signed purchase orders from AALTO HAPS for the Company's 450 Wh/kg ultra-high-energy density SiMaxx cells. Amprius' 450 Wh/kg SiMaxx cells are designed to operate in some of the most extreme flight conditions while maximizing flight range and payload capacity. These attributes make SiMaxx cells the only known commercially available batteries capable of supplying enough endurance for persistent HAPS (High-Altitude Platform Stations) overnight stratospheric flight operations in all seasons or at higher latitudes.

This is a key consideration for AALTO, with Zephyr the only fixed-wing HAPS to have demonstrated day and night longevity in the stratosphere. The collaborative efforts between AALTO and Amprius reached a milestone in 2022 with a record-breaking 64-day cross-continental test flight of a Zephyr 8/S, a monumental achievement for both companies. During the event, Amprius' 400 Wh/kg high-energy cells powered the flight without descending from the stratosphere, allowing AALTO to break its own previous record of more than 25 days.

Amprius' SiMaxx cells are equipped to operate in challenging environments and are, therefore, ideally suited for aviation and military applications. Amprius began fulfilling shipments against the new AALTO purchase orders in First Quarter of 2024 and expects to continue fulfilling shipments in the coming months as the Company advances its efforts to increase its SiMaxx production capacity in Fremont, CA.