Jesus battery HEALS ITSELF
http://www.theregister.co.uk/2013/11/18/battery_heal_thyself_stanford_boffins_produce_lectrode/ Self-HEALING BATTERY could make electric cars practical at last By Lewis Page 18th November 2013 [video http://www.youtube.com/watch?v=ZwacIv63XcE Balloon Coated with Self-Healing Polymer SLAC National Accelerator Laboratory · Nov 12, 2013 To show how flexible their self-healing polymer is, researchers coated a balloon with it and then inflated and deflated the balloon repeatedly, mimicking the swelling and shrinking of a silicon electrode during battery operation. The polymer stretches but does not crack. (Brad Plummer/SLAC) ] Stanford boffins' remarkable cladding produced Miracle-'lectrode Top boffins at Stanford uni say they have cracked a key problem afflicting today's lithium-ion batteries, which might make the next generation of phones, e-cars and other battery powered kit much, much better. The problem the researchers have tackled is that silicon - though an excellent material for a modern battery electrode, as it has a high capacity for absorbing and then releasing lithium ions during charging and discharging - swells up and shrinks massively when so used. In fact a silicon electrode increases in size by no less than three times over and then returns to its original size duing a charge-discharge cycle, and this naturally tends to mean that it comes to bits in fairly short order. This is a major underlying reason why li-ion batteries often have a fairly poor service life. That's not a crippling problem in a smartphone - even if it's an iPhone or similar, designed in such a way that it's hard to replace the battery, people tend to get a new phone quite often. But it is a big deal in a much more expensive electric car: while a lot of people change cars frequently, they expect them still to be in saleable condition when they've finished with them - without any need to replace the major component of the power train. The general distrust felt by the motor industry regarding battery service life, based on many years of beta tests with small groups of vehicles, is one major reason why not very many battery cars are being made. Even Tesla Motors, the flagship firm for battery cars, has admitted in SEC filings that battery life may yet become a major problem for it as its cars age. But now the Stanford boffins say they're on the track of a fix. They have developed an astronishingly strong and stretchy polymer which can be coated onto a silicon electrode in use. As cracks form, the coating "heals" them. Here's a vid of a balloon coated with the stuff being inflated and deflated, indicating just how stretchy it is: “Self-healing is very important for the survival and long lifetimes of animals and plants,” says Chao Wang, a postdoc researcher at Stanford. “We want to incorporate this feature into lithium ion batteries so they will have a long lifetime as well.” Thus far, the silicon+gunge electrodes aren't ready for prime time: they can only do 100 charge cycles before starting to lose performance. “That’s still quite a way from the goal of about 500 cycles for cell phones and 3,000 cycles for an electric vehicle,” admits Wang's colleague professor Yi Cui, “but the promise is there, and from all our data it looks like it’s working.” So this technology isn't going to manufacturing yet, or perhaps ever if it can't be improved. But it is impressive enough that it has led to an article by the Stanford lab crew getting published in Nature Chemistry. And perhaps the amazing stretchy-stuff might have other uses, as well. [© 2013 theregister.co.uk] http://www.theregister.co.uk/2013/11/18/battery_heal_thyself_stanford_boffins_produce_lectrode/ Jesus battery HEALS ITSELF, might make electric cars practical at last 18th November 2013 ... still quite a way from the goal of ... 3,000 cycles for an electric vehicle,” ... “but the promise is there, and from all our data it looks like it’s working.” ... this technology isn't going to manufacturing yet ... For all EVLN posts use: http://electric-vehicle-discussion-list.413529.n4.nabble.com/template/NamlServlet.jtp?macro=search_page&node=413529&query=evln&sort=date Here are today's archive-only EV posts: EVLN: Barcelona, EV capital of the world & cleanest bus fleet in Europe EVLN: Kona Electric Ute, A Cool Electric Cargo Bike! EVLN: Can a condo owner insist on having EVSE access? EVLN: Elon's giving BMW i3 EV owners a solar-installation discount EVLN: RSPB-charity’s Zoe & Kangoo EVs recharged from HQ's wind turbine + EVLN: Convert Tusker had +5k incident-free miles in company Leaf EV {brucedp.150m.com} -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-SLAC-Self-Healing-polymer-for-better-li-ion-service-life-video-tp4666353.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
