Issue 45 | Uncrewed Systems Technology Aug/Sept 2022 Tidewie USV Tupan | Performance monitoring | Bayonet 350 | UAVs insight | Xponential 2022 | ULPower UL350i and UL350iHPS | Elroy Air Chaparral | Gimbals | Clogworks Dark Matter

78 Show report | AUVSI Xponential 2022 and multi-fuel efficiency for UAVs in shipborne and coastal operations,” said Alexander Vaughn. “We’ve also worked closely on better integrating the ancillary systems to run more smoothly and efficiently off the engine, and we’re even starting to look into burning hydrogen for zero-emissions propulsion.” The 225CS weighs 10 kg and outputs up to 30 kW, while the 80S weighs 5 kg and produces a peak power of 9 kW. Both engines integrate the company’s patented SPARCS (Self-Pressurising Air Rotor Cooling System) technology, which uses blow-by gases captured via side vents as a cooling medium. That enables efficient thermal management of the rotor as well as recapturing oil lost during compression, and preventing the high oil consumption and related emissions typical of some Wankel configurations. The system’s heat exchanger can be mounted outside the engine or inside the rotor housing, with the latter configuration patented as Compact SPARCS. Amprius exhibited the latest products in its range of highly SWaP- optimised lithium-ion battery cells, which have been developed around a patented silicon nanowire anode technology to achieve a range of useful performance parameters. “Silicon nanowire has a higher capacity than conventional graphite anodes – 10 times higher in fact,” explained Daniel Seo. “That means we can use much less anode material than in conventional cells, which reduces the weight of our cells without lowering their energy capacity. In general, that equates to higher energy density – a mission-critical quality for UAVs.” He added that the high surface area of nanowires can also be used in their designs to contribute to a higher power charge and discharge capability (with lower chance of lithium dendrite build- ups). That can be vital for sensors, processing, propulsion and other key functions of many autonomous systems. Among the company’s product portfolio are a high energy density cell that weighs 46.5 g and contains up to 21 Wh and 5.8 Ah. It charges and discharges at a constant rate of 1.16 A at 5C, between 2.75 and 4.42 V. Amprius also has a high-power fast- charge cell that carries up to 10 Wh and 2.75 Ah, charges at a constant rate of 2.75 A (1C) and discharges at 8.25 A (3C) up to a peak continuous discharge rate of 12.5 A (5C), while weighing 28 g. Both cells are assembled with lithium cobalt oxide cathodes, while the company’s 44 g high energy density power cell uses an NMC cathode to achieve a 15.6 A maximum continuous discharge (at 3C) from its 18 Wh energy store. August/September 2022 | Uncrewed Systems Technology The 80S from Advanced Innovative Engineering weighs 5 kg and produces up to 9 kW Amprius’ lithium-ion cells incorporate silicon nanowire anodes