 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
| . |  |
. |
 by Staff Writers Evanston IL (SPX) May 30, 2018
A Northwestern University research team has found ways to stabilize a new battery with a record-high charge capacity. Based on a lithium-manganese-oxide cathode, the breakthrough could enable smart phones and battery-powered automobiles to last more than twice as long between charges. "This battery electrode has realized one of the highest-ever reported capacities for all transition-metal-oxide-based electrodes. It's more than double the capacity of materials currently in your cell phone or laptop," said Christopher Wolverton, the Jerome B. Cohen Professor of Materials Science and Engineering in Northwestern's McCormick School of Engineering, who led the study. "This sort of high capacity would represent a large advancement to the goal of lithium-ion batteries for electric vehicles." The study was published online May 14 in Science Advances. Lithium-ion batteries work by shuttling lithium ions back and forth between the anode and the cathode. The cathode is made from a compound that comprises lithium ions, a transition metal and oxygen. The transition metal, typically cobalt, effectively stores and releases electrical energy when lithium ions move from the anode to the cathode and back. The capacity of the cathode is then limited by the number of electrons in the transition metal that can participate in the reaction. A French research team first reported the large-capacity lithium-manganese-oxide compound in 2016. By replacing the traditional cobalt with less expensive manganese, the team developed a cheaper electrode with more than double the capacity. But it was not without its challenges. The battery's performance degraded so significantly within the first two cycles that researchers did not consider it commercially viable. They also did not fully understand the chemical origin of the large capacity or the degradation. After composing a detailed, atom-by-atom picture of the cathode, Wolverton's team discovered the reason behind the material's high capacity: It forces oxygen to participate in the reaction process. By using oxygen - in addition to the transition metal - to store and release electrical energy, the battery has a higher capacity to store and use more lithium. Next, the Northwestern team turned its focus to stabilizing the battery in order to prevent its swift degradation. "Armed with the knowledge of the charging process, we used high-throughput computations to scan through the periodic table to find new ways to alloy this compound with other elements that could enhance the battery's performance," said Zhenpeng Yao, co-first author of the paper and a former Ph.D. student in Wolverton's laboratory. The computations pinpointed two elements: chromium and vanadium. The team predicts that mixing either element with lithium-manganese-oxide will produce stable compounds that maintain the cathode's unprecedented high capacity. Next, Wolverton and his collaborators will experimentally test these theoretical compounds in the laboratory.
Better, faster, stronger: Building batteries that don't go boom Houghton MI (SPX) May 31, 2018 There's an old saying: "You must learn to walk before you learn to run." Despite such wisdom, numerous industries skip the basics and sign up for marathons instead, including the battery industry. Lithium ion batteries hold incredible promise for improved storage capacity, but they are volatile. We've all heard the news about lithium ion batteries in phones - most notably the Samsung Galaxy 7 - causing phones to catch fire. Much of the problem arises from the use of flammable liquid electrol ... read more
|
|||||||||||||
|
|
| The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |
del.icio.us
Digg
Reddit
Google
