Treceți la conținutul principal

Laptop cu baterie care ţine 40 de ore?

Imagine running your laptop nonstop from New York to Tokyo -- crunch some numbers, work on a memo pop in a few DVDs -- and then do a full day of meetings, using your machine throughout the day and into the night. Imagine doing all this without ever plugging in your computer to recharge its battery.

This scenario may become reality in the near future, if Stanford University scientists succeed in commercializing a breakthrough in the laboratory. Assistant Professor Yi Cui and associates at Stanford's Department of Materials Science and Engineering said they have developed a method to increase the life of rechargeable lithium ion batteries to a whopping 40 hours.

Publishing in the journal Nature Nanotechnology, the Stanford researchers have shown that by using silicon nanowires as the battery anode instead of today's graphite, the amount of lithium the anode can hold is extended tenfold.

Revolution in Battery Design

"It's not a small improvement," Cui said. "It's a revolutionary development." And Cui means to move the development out of the lab as soon as possible. "We are working on scaling up and evaluating the cost of our technology," Cui said. "There are no roadblocks for either of these."

Cui has filed a patent on the technology and is evaluating the formation of a company or licensing the technology to a battery manufacturer. Potentially two-day batteries could be on the market within "several years," he said.

Silicon anodes are not a new idea. Researchers have known for some 30 years that they have the "highest theoretical charge capacity," but, until now, they haven't been practical because they change volume by 400 percent as lithium is inserted and extracted, the journal said. Cui's solution: a sponge-like network of tiny silicon nanowires, each of which expands but doesn't fracture.

"Nanowires grown directly on the current collector do not pulverize or break into smaller particles after cycling," the journal reports. "Rather, facile strain relaxation in the nanowires allows them to increase in diameter and length without breaking."

The Many Advantages of Nanowires

Not only can the nanowires handle the extreme volume changes, they also "provide good electronic contact and conduction, and display short lithium insertion distances," Cui wrote. "We achieved the theoretical charge capacity for silicon anodes and maintained a discharge capacity close to 75 percent of this maximum, with little fading during cycling."

The nanowires are grown directly on the metallic substrate that collects current, a process that has several advantages, Cui explained. First, the nanowires' small diameter can better accommodate the four-fold expansion in volume without fracturing. In addition, each nanowire is electrically connected to the metallic current collector, so all the nanowires contribute to battery capacity.

The nanowires also offer efficient "charge transport" and eliminate the need for additives to conduct electricity, which add weight, the journal stated. In addition to Cui, the researchers were Candace K. Chan, Hailin Peng, Gao Liu, Kevin McIlwrath, Xiao Feng Zhang and Robert A. Huggins

Comentarii

Postări populare de pe acest blog

Paris Hilton sucks

Prezentatoarea show-ului de dimineata de la MSNBC care n-a vrut sa citeasca stirea despre Paris Hilton se numeste Mika Brzezinski si este - ati ghicit - fiica lui Zbigniew Brzezinski. O vedeti pe vreo fufa de la noi facand asa ceva? Macar in semn de protest fata de stirile cu Bheeekali...

Presa din Ungaria: "Banca lui Vladimir Putin se mută la Budapesta". România, printre acţionarii IIB

email   print 0     Autor:  Emil Neacşu 21 Feb 2019 - 14:16 Mutare strategică a preşedintelui rus, Vladimir Putin. Potrivit site-ului  Index.hu ,  International Investment Bank  îşi mută sediul general de la Moscova la Budapesta. Potrivit site-ului Băncii, România este printre acţionarii săi. Parlamentul Ungariei a dezbătut acordul internaţional care stabileşte noul sediu al băncii, acord care conţine o serie de detalii alarmante. Propunerea legislativă pentru introducerea unui nou acord internaţional cu Rusia în sistemul legal ungar conţine o serie de detalii neobişnuite, care acordă o serie de drepturi suplimentare pentru International Investment Bank (IIB), care este succesorul legal al Comecon şi al băncii fostei organizaţii economice sovietice. Documentul prevede că mare parte din costurile băncii - inclusiv remobilarea, chiria şi securitatea - să fie plătite de contribuabilii maghiari.  Presa ungară a subliniat că acordul menţionează o

links

https://www.nationalgeographic.com/culture/topics/reference/dramatic-history-prorogation-british-parliament/ https://foreignpolicy.com/2019/08/29/shutting-down-parliament-is-worse-than-a-coup-its-a-mistake/ https://time.com/5654052/moldova-drinking-problem/