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Rice University Adds Asphalt To Speed Lithium Metal Battery Charging By 20 Times (nextbigfuture.com)
schwit1 writes: The Rice lab of chemist James Tour developed anodes comprising porous carbon made from asphalt that showed exceptional stability after more than 500 charge-discharge cycles. A high-current density of 20 milliamps per square centimeter demonstrated the material's promise for use in rapid charge and discharge devices that require high-power density. The Tour lab previously used a derivative of asphalt -- specifically, untreated gilsonite, the same type used for the battery -- to capture greenhouse gases from natural gas. This time, the researchers mixed asphalt with conductive graphene nanoribbons and coated the composite with lithium metal through electrochemical deposition. The lab combined the anode with a sulfurized-carbon cathode to make full batteries for testing. The batteries showed a high-power density of 1,322 watts per kilogram and high-energy density of 943 watt-hours per kilogram. Testing revealed another significant benefit: The carbon mitigated the formation of lithium dendrites. These mossy deposits invade a battery's electrolyte. If they extend far enough, they short-circuit the anode and cathode and can cause the battery to fail, catch fire or explode. But the asphalt-derived carbon prevents any dendrite formation.
"The capacity of these batteries is enormous, but what is equally remarkable is that we can bring them from zero charge to full charge in five minutes, rather than the typical two hours or more needed with other batteries," Tour said. "While the capacity between the former and this new battery is similar, approaching the theoretical limit of lithium metal, the new asphalt-derived carbon can take up more lithium metal per unit area, and it is much simpler and cheaper to make. There is no chemical vapor deposition step, no e-beam deposition step and no need to grow nanotubes from graphene, so manufacturing is greatly simplified." The findings have been published in the journal ACS Nano.
"The capacity of these batteries is enormous, but what is equally remarkable is that we can bring them from zero charge to full charge in five minutes, rather than the typical two hours or more needed with other batteries," Tour said. "While the capacity between the former and this new battery is similar, approaching the theoretical limit of lithium metal, the new asphalt-derived carbon can take up more lithium metal per unit area, and it is much simpler and cheaper to make. There is no chemical vapor deposition step, no e-beam deposition step and no need to grow nanotubes from graphene, so manufacturing is greatly simplified." The findings have been published in the journal ACS Nano.
Let's hope this isn't patented, so that anyone can use the research. Universities have a habit of taking federal funds, then patenting the research that those funds produce. This research was partly funded by the Air Force Office of Scientific Research. Congress should repeal the Bayh-Dole Act and require that any innovations from federally funded research be placed in the public domain.
At 943 WH/kg and 1322 W/kg, this is really quite good. According to wikipedia, this is 4x "traditional" Li-ion density in terms of storage and decent in terms of charge/discharge rate.
I know they tested 500 cycles. Get to 1000 and it is practical. Get to 5000 and it owns the market.
So any /.er knows battery "breakthroughs" are once a month or more on average (or so it seems). But most, or so far one supposes all, of them have major problems. A battery needs to hit high power density, IE how much power it can deliver over time. High energy density/specific energy, IE how much energy it can store per liter and per kilogram. It needs to be able to last over a long amount of charge/discharge cycles, because if your battery loses too much energy/shorts/explodes after a few charges then it's useless. And it needs to be cheap to make.
Well, surprise, but somehow this one seems to be the announcement that, could, hit all of those points. The reported numbers are several times the current best for li-on power density, energy density (assumedly for both volume and weight), lasts a lot of charge and discharge cycles, and doesn't require some exotic rare earth material to make. Assuming the actual creation process isn't exotic or complex, IE can be economically scaled, this could actually be the coming of the affordable electric car/smartphone battery that actually lasts all day/etc. that's been promised for a while now. Here's fuckin hoping.
That might be an exaggeration... but seriously. After 15 years of reading amazing stuff on Slashdot, the amount of that stuff that actually becomes something beyond "University discovery" even 5+ years out from the initial story is depressingly tiny.
Over the last decade batteries have improved dramatically in capacity, reliability, charging speed, and (especially) cost. This is a result of the very breakthroughs that you so flippantly denigrate.
If you aren't interested in reading about leading edge research, then what are you doing on Slashdot?
Welcome to the world of research! The gap between physical possibilities and economical viability is large, but without sufficient breakthroughs on physical possibilities we will never find one that is economically viable.So, regardless of the chances being slim that we will reap the benefits of all these breakthroughs anytime soon, I am still happy to see such breakthroughs happen.
Not only that, but reading that they used asphalt for this makes me think I'm driving on the biggest darn battery everyday (I know, it's not true... still...;)
Really? Because 15 years ago I certainly didn't have 3Ah battery capable of being charged in 30min and only 4mm thick sitting in my pocket.
He is here to post, not read anything he posts about.