Your editor’s first outing at an electric aircraft symposium was in 2009. At that meeting, Dr. Yi Cui, Stanford professor and battery expert, talked about silicon and its energy density being so much greater than that for graphite. He predicted huge advances for battery chemistry – and now he’s delivering. His firm, Amprius, is shipping 450 Watt-hour per kilogram batteries. Unlike many such companies, Amprius is not projecting these numbers several years out, but delivering now. According to their February 8 press release, Amprius sent its first batch of the energy-dense cells, “…To an industry leader of a new generation of High-Altitude Pseudo Satellites (HAPS).” Your editor guesses that leader is Zephyr, acquired by Airbus and setting endurance records on solar and battery power since its introduction in 2017. One reached 76,100 feet in a 2021 campaign, spending over 36 days (in two flights) at stratospheric heights and equaling the sailplane altitude record set by the Perlan Project in 2018. …
Amprius, Airbus, Silicon and Batteries
Batteries are a tough study. We see many different roads being traveled in attempts to reach the Nirvana of the lightest, most powerful energy storage cell ever. We see continuing shortfalls because of the much chemistries that seem never to work out as hoped. Several recent articles, though, showed links that forced your editor into a deep study of battery developments first heard about a decade ago. These involved Yi Cui, Stanford professor and battery guru, silicon electrodes, and a new electrolyte that holds thing together. Presaging recent developments, your editor first heard Yi Cui present at the 2009 CAFE Foundation Electric Aircraft Symposium. Then, he predicted, based on the theoretical limits for silicon-based electrodes in batteries, that we would see 10X (greater energy density than then available) batteries in the not-too-distant future. A decade later, his company Amprius may be edging toward that goal with new funding from Airbus. Since then, Cui, his students and associates have helped boost …