Giving Power Walking a Whole New Meaning

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Georgia Institute of Technology researchers have developed a self-charging power cell that uses a piezoelectric membrane to convert mechanical energy to chemical energy, then stores that energy until it can be released as en electrical current. Combining the power generator with the energy storage device, this hybrid is claimed to be more efficient than systems with separate generators and batteries.  When the piezoelectric membrane is flexed, it moves lithium ions in the power cell from one side of the cell to the other. Membranes in shoe heels and soles could produce power when a person walked, powering small electronic devices such as calculators or cell phones. Zhong Lin Wang, a Regents professor in the School of Materials Science and Engineering Georgia Tech, explains the distinguishing feature of his team’s innovation. “People are accustomed to considering electrical generation and storage as two separate operations done in two separate units. We have put them together in a single hybrid unit to create a …

Better Batteries: Nickel Cobalt Manganese from Ricardo and Axeon

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Ricardo and Allied Vehicles, a British engineering firm known for its work with racing vehicles and KERS technology, has announced an alliance with European battery manufacturer Axeon to produce a Nickel Cobalt Manganese (NCM) battery which would reputedly provide 35-percent greater range to electric vehicles than “existing technologies at the same weight.” The new battery would require “50 percent less volume and 30 percent less mass when compared to Lithium Iron Phosphate chemistry at cell level,” according to the Richardo fourth quarter, 2011 newsletter. Green Car Congress reports, “Electrochemically, the performance is superior to Lithium iron phosphate (LiFePO4) and Lithium cobalt oxide (LiCoO2) in terms of capacity and therefore energy density. In  terms of rate capability and therefore power density the electrochemical performance is better than LiCoO2 but not as high as LiFePO4, Axeon says.”  The chemistry compromise allows lower costs for these batteries. With a Ricard-designed battery management system (BMS) the NCM pouch cells, new technology for EVs, can be …

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 …