Amprius Announces 500 Watt-Hour per Kilogram Cell

Dean Sigler Announcements, Batteries, Sustainable Aviation Leave a Comment

Amprius has announced a 500 Watt-hour per kilogram cell, essentially doubling the energy density available up to now.  Remember, though, that cell-levels of energy drop as the cells are incorporated into modules and packs, carrying the burdens of containment packaging, bus bars, and battery management systems (BMS) that lower total output.  Pack levels will be lower. Slow Progress This comes as the culmination of at least 14 year’s work, starting with Yi Cui’s work at Stanford University.  Your editor first saw him at a 2009 CAFE Foundation symposium at the Hiller Aviation Museum in San Carlos, California.  He was a proponent of the 10X battery, which at that time would have meant 10 times the energy storage of then typical cells, or around 10 times the 200 Watt-hours per kilogram then considered to be a respectable achievement. This blog reported in 2013, “According to Green Car Congress, ‘The company has also demonstrated greater than 650 and 700 Wh/L batteries with …

Surfing, Beaches and Sandy Batteries

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

According to scientific history, or perhaps legend, Archimedes had his Eureka moment when settling into his bathtub and seeing the water rise around him.  He came up with his idea that a body’s mass displaced an equal amount of water, something that’s proved to be useful to know. Zachary Favors, a graduate student at the University of California at Riverside, had a similar moment of discovery when leaving the water after surfing near the beaches of San Clemente.  According to the UCR press release, “he picked up some sand, took a close look at it and saw it was made up primarily of quartz, or silicon dioxide.”  This led him to research locations in the United States where sand with high proportions of quartz existed.  He found that the Cedar Creek Reservoir, east of Dallas, had sand with the qualities for which he was searching. Not only that, it was close to his boyhood home. What would lead him to …

Cheaper, Lighter, Stronger – But When?

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

We’d all love to see the battery that’s lighter, stronger, charges like a capacitor and costs next to nothing.  We’d all be driving electric cars and those of us who wanted battery-powered airplanes would be designing the next new wave of flight. Usually, these things are a decade or more away, following excruciating intervals of study, commercialization and usually, much-delayed or postponed production. Dr. Chongwu Zhou, a professor at the University of Southern California’s (USC’s) Viterbi School of Engineering, claims to have such a battery under provisional patent, and potentially available commercially within “two or three years,” according to school press releases. The battery uses porous silicon nanoparticles to replace traditional graphite anodes and provide superior performance – three times as much energy as a graphite-based lithium battery and capable of being recharged within only 10 minutes. Zhou says, “It’s an exciting research. It opens the door for the design of the next generation lithium-ion batteries.” Zhou worked with USC graduate …

Dr. Jaephil Cho’s Powerful Silicon Nanotubes

Dean Sigler Sustainable Aviation 1 Comment

Shortly before appearing at the fourth Annual Electric Aircraft Symposium at Rohnert Park, California, Dr. Jaephil Cho was interviewed by Esther Levy of Material Views, an online resource dealing with, as the title implies, high-technology materials.  Dr. Cho, Dean of the new Interdisciplinary School of Green Energy at Ulsan National Institute of Science & Technology (UNIST), works with lithium-ion cells, and along with Dr. Yi Cui of Stanford University, is considered among the most forward thinking researchers in the field. Where Dr. Cui’s efforts are related to development of better cathodes, Dr. Cho’s work focuses on improving anode performance. Their efforts have led to an 80-percent improvement in cathode performance, as reported in Dr. Cui’s presentation at EAS III, and a 62-percent improvement in anode performance, according to Dr. Cho’s report at EAS IV. Considering that “normal” battery advancement has been on the order of 10 percent per year for the last few decades, either of these announcements should be …