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Power Science Technology

Crushed Silicon Triples Life of Li-Ion Batteries In the Lab 123

derekmead writes "Batteries rule everything around us, which makes breakthroughs a big deal. A research team at Rice says they have produced a nice jump: by using a crushed silicon anode in a lithium-ion battery, they claim to have nearly tripled the energy density of current li-ion designs. Engineer Sibani Lisa Biswal and research scientist Madhuri Thakur reported in Nature's Scientific Reports (it has yet to be published online) that by taking porous silicon and crushing it, they were able to dramatically decrease the volume required for anode material. Silicon has long been looked at as an anode material because it holds up to ten times more lithium ions than graphite, which is most commonly used commercially. But it's previously been difficult to create a silicon anode with enough surface area to cycle reliably. Silicon also expands when it's lithiated, making it harder to produce a dense anode material. After previously testing a porous silicon 'sponge,' the duo decided to try crushing the sponges to make them more compact. The result is a new battery design that holds a charge of 1,000 milliamp hours per gram through 600 tested charge cycles of two hours charging, two hours discharging. According to the team, current graphite anodes can only handle 350 mAh/g."
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Crushed Silicon Triples Life of Li-Ion Batteries In the Lab

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  • by InvisibleClergy ( 1430277 ) on Friday November 02, 2012 @01:28PM (#41855965)

    get back in the car, this Safari is over!

  • by Anonymous Coward

    Lithium battery developments come almost as fast as "new cure for cancer"...and few of them get out of the lab.

  • by Anonymous Coward on Friday November 02, 2012 @01:36PM (#41856093)

    As we know from recent experience, Lithium is flammable, and something flammable, even explosive, can NEVER replace Gasoline, which is safe and has never burned anybody.

    Surely they realize the futility of their methods, and we can go back to our safe and harmless internal combustion engines?

    • Comment removed based on user account deletion
      • As we know from recent experience, Hydrogen is flammable, and something flammable, even explosive, can NEVER replace Gasoline, which is safe and has never burned anybody. Surely they realize the futility of their methods, and we can go back to our safe and harmless internal combustion engines?

        FTFY

        Give it some time... The Universal Ingredient Label [xkcd.com]

    • Letting your sarcasm go whoosh for a moment...

      The energy density [wikipedia.org] of a lithium-ion battery is currently about 1/6th that of gasoline and this improvement will take it up to nearly 1/3rd. But of course, gasoline isn't recharable. And the energy density of gasoline is highly unlikely to improve further, while batteries certainly will. So it is no exaggeration to say that this development basically seals the deal for electricity vs gasoline. My next car will most certainly be all electric, and it will be a beas

      • Excuse me... "will take it up to nearly one half".

        • by sodul ( 833177 )

          We should keep the overall efficiency of the fuel and the engine in mind. The traditional gazoline engines only have a 30%to 40% efficiency in the best case (40% to 50% for diesel), while electrical engines are usually over 90%. Add to that the electrical car can get energy back when breaking while it is pure loss for gasoline, and you have now an electrical car that has a longer range than a gasoline car.

          http://en.wikipedia.org/wiki/Brake_specific_fuel_consumption [wikipedia.org]
          http://en.wikipedia.org/wiki/Premium_effici [wikipedia.org]

  • by frovingslosh ( 582462 ) on Friday November 02, 2012 @01:38PM (#41856119)
    In recent years I've read, right here on Slashdot, about a couple of new li-on breakthroughs that we were told would be giving us 10x improvements, And at least one was claimed to be easily applied to current manufacturing techniques. So why should I believe this? And why should I get excited about a 3X "improvement" when we;ve already been told about 10X improvements?
    • by h4rr4r ( 612664 )

      If you want to only hear about consumer products go somewhere else.

      This is slashdot.

      • To the credit of whoever submitted the summary, this one was explicit about, "Something worked well in a lab", instead of the usual, "Your Batteries Will Soon Be 3x's Better!"

    • 10 x 3 = 30

    • by Anonymous Coward on Friday November 02, 2012 @02:13PM (#41856665)

      There's several areas which are ripe for improvement in batteries.

      1) Power density.
      2) Recharge cycles.
      3) Charge time.
      4) Charge efficiency.
      5) Shelf drain.

      Even if a certain technology gives a 10x improvement on one of those, it may turn out to have a negative impact on one (or more) of the others, and therefore not be worth marketing.

      Example:
      My new battery technology improves cuts charge time in half! It also cuts power density by a factor of 3. In certain, specific scenarios it might still be worth using one of these new batteries, but in general, it's won't be.

    • Because this is how we improved Carbon-Zinc and Alkaline dramatically.
    • by PRMan ( 959735 )
      Laptops today have around 5-6 hours of battery life. Even 5 years ago, 2 1/2 hours was a long time. So, I'm seeing that several of these technologies have helped a great deal.
      • by Guspaz ( 556486 ) on Friday November 02, 2012 @02:40PM (#41857179)

        Part of it is advancements in batteries, but the other part is improvements in power consumption. Five years ago, LED backlights were rare, and CFL backlights were common. Today, I'm not sure if you could even find a CFL backlight in a notebook. LEDs are a bunch more power efficient than CFLs, and the backlight has always been one of if not the largest consumer of power on average in a notebook. Even when the notebook isn't doing any other work, it needs to keep the screen lit up for the user to see what's on it.

        • What we actually need to do is compare old battery packs to new ones, that's the only thing which will give us reliable density improvements. Looking at all of the other improvements doesn't actually affect the physical density of the battery, which is what this technology (and the previous "breakthroughs") claim to achieve. Most laptops still come with in-a-metal-tube battery cells, which are much heavier and have big air gaps that don't need to be there. Compare this to your cellphone battery and you'll s

          • by Guspaz ( 556486 )

            That's not really the case for a lot of laptops though. Any tablet convertible, any ultrabook, any macbook, any Chromebook, anything with an integrated battery, they're all lithium polymer. I suspect that if you add up all lithium polymer laptops, they'd be a rather large part of the notebook market.

        • by MrBeau ( 1009661 )
          CFL and LED are very close in luminous efficacy. http://en.wikipedia.org/wiki/Luminous_efficacy [wikipedia.org]
          • by Khyber ( 864651 )

            No, they are not.

            We've got LED kicking the pants off of CFL by roughly triple the photon flux density per watt.

            Wikipedia is not reliable. Those sources are way outdated. We've got 1W diodes pumping 150 lux/W and Cree has already smashed past 200 lux/w and did that last year. Arrays of these diodes pump out huge amounts of light.

            ~designs horticultural LED and interior LED lighting

            • by MrBeau ( 1009661 )
              Cool. I stand corrected. Maybe update WP?
              • by Khyber ( 864651 )

                I refuse to update that place. They'll as always cite 'original research' and wipe it out. Had it happen many times.

                • by MrBeau ( 1009661 )
                  I wanted to update the page but they, understandably, do not except press reports. I can't find an independent source for the Cree results. Can you provide me with a source for the 150lm/W diodes? A datasheet maybe?
                  • by Khyber ( 864651 )

                    Go look all over alibaba.com - most of the newer 1000w spotlights are pushing 170,000 lumens or more, for 170l/w.

                    It's already been mainstream for well over a year.

                  • Cree has this page [cree.com] crowing about one of their their CXA series modules being 108 lm/W at 85c and 119 lm/W at 25c. I haven't found anything higher. Here's the datasheet [cree.com].

    • by Guspaz ( 556486 ) on Friday November 02, 2012 @02:38PM (#41857139)

      Lithium ion batteries improve at a rate of 8-10% per year. So, if we take into account that a lot of the lab claims are exaggerated, a "10X" breakthrough that actually provides a 2X improvement and takes 7-8 years to hit the consumer market is pretty much in line with the expected curve.

    • by Twinbee ( 767046 )
      I think you may be talking about Lithium Air with the 10x thing. Those are more meant for cars than general purpose I think as they need a constant influx of air. I'm only 65% sure of that that though, so maybe someone can confirm.
    • Something that would be new is using Li instead of Pb in the original 12V car battery. What is the hold up on that?
      • by MrBeau ( 1009661 )
        Pb is cheap, reliable, safe, doesn't need a complex battery management system and weight is not a big concern.
        • weight is not a big concern
          .

          So how would you explain the use of "space-saver" spares? They are chosen for their aesthetics?

          • by sodul ( 833177 )

            They are 'space' savers, not 'weight' savers ? The spare tires are usually in the trunk where you want maximum storage while the 12V battery is under the hood, where things are crammed but most consumers would rather see that the space is fully used rather than seeing a lot of empty space where the engine lives.

    • Droid 4 owner here... I need a battery made with this technology NOW. Maybe then a charge would last a whole work day.

    • Someone should invent a generator powered by stories about battery breakthroughs.
  • Well, it's nice to see silicon winning back some ground from the Carbon Assault. The question is whether its new future in power systems makes up for losing its long-time prominence in microelectronics or whether batteries are just a consolation prize.
    • We can recycle our batteries to be turned into electronics and our electronics to be turned into batteries. What a beautiful coincidence.

    • And last time I checked, silicon doesn't burn merrily like graphite does.

  • I never would have thought my first electric car would be powered by sand!
  • Hopefully outside of the lab this translates into more than just "5% better life in real world conditions", or isn't totally unusable because the anodes crumble after 10 discharges or something. There is a LOT of work going into batteries these days, and it seems like some of it has to eventually pan out.
    • Re: (Score:3, Insightful)

      by mlts ( 1038732 )

      First question that comes to mind. What voltage are these batteries at? 1000 amp-hours at 12 volts is a lot different than 1000 amp-hours at 120.

      Gasoline gets 12,000 watt-hours as a reference.

      As for these batteries, I am hoping for use in larger applications than just a skinner smartphone.

      One amp-hour per gram is pretty good, assuming this is a twelve volt battery. Compare that to a deep cycle lead-acid battery that weighs about 18 kilograms and gives 150 AH or so. For the same amount of energy as that

      • Nominal li-Ion cell voltage is 3.7 volts. http://en.wikipedia.org/wiki/Lithium-ion_battery [wikipedia.org]. Which makes you wonder about the 1,000 mAh/g versus 350 mAh/g figures they quote, since they aren't the normal units for specific energy, specific power, or energy density. They also don't work out right if you assume the nominal cell voltage either.

        • by grqb ( 410789 )

          Battery materials are reported in mAh/g because this way they are independent of the battery size. You could stuff say 50g of this material into a battery meant for a car or 1/2g of this material into a battery meant for testing in a lab and you can roughly estimate the energy storage abitlity of the material. Both of these cells will have a voltage of about 3.7V on average. The units of mAh/g tells you about the amount of lithium that can be stored by this particular material so that it can be compared aga

  • Companies will reduce the size of the battery two thirds and still charge the same amount of money for it. Battery life will appear to remain the same to the end users.

    • by h4rr4r ( 612664 )

      You fail econ 101.
      Worst case the devices using this will get lighter and battery life will stay the same.

    • No way they would do that for cars and phones that desperately need more power. Well, Apple might because thinness is their #1 priority.

    • by alexander_686 ( 957440 ) on Friday November 02, 2012 @02:14PM (#41856689)

      Your making the assumption that the cost reduction in using fewer materials offsets the new manufacturing process – which we don’t know (could be high, lower, or the same).

      For years we have been able to manufacture cars that get better gas mileage by switching from steel to aluminum, carbon fibers, etc – but we have never done it because the cost of the lighter materials (both in manufacturing and maintenance) are higher.

    • Companies will reduce the size of the battery two thirds and still charge the same amount of money for it.

      You mean, Apple will. The real world will obey the laws of economics.

  • by Obfuscant ( 592200 ) on Friday November 02, 2012 @01:45PM (#41856251)
    My cellphone battery is nearly dead, so please may I squeeze it up between your lovely knockers, my dear? Oh, they're natural? Nevermind...
    • by N!k0N ( 883435 )
      crushed silicon ... not _silicone_... easy mistake to make though.
    • That's not the right material anyways. If you want to see what silicon boobs would be like, watch Sacha Baron Cohen's "The Dictator."

  • A lithium battery holding three times the capacity is significant. This could mean that the range of a EV could be three times, all else equal, or the battery could provide three times the voltage with the same capacity all else equal, or simply the size and weight of the battery could be 1/3rd the size leaving room for other components. Considering I race RC cars with lithium batteries in a six minute heat, I'd choose 1/3rd the size and weight.
    • by fahrbot-bot ( 874524 ) on Friday November 02, 2012 @02:06PM (#41856559)

      A lithium battery holding three times the capacity is significant. This could mean that the range of a EV could be three times, all else equal, or the battery could provide three times the voltage with the same capacity all else equal, or simply the size and weight of the battery could be 1/3rd the size leaving room for other components.

      Thanks, Captain Obvious, for clearly explaining the ramifications of "3x" ... :-)

    • by Githaron ( 2462596 ) on Friday November 02, 2012 @02:11PM (#41856635)

      I'd choose 1/3rd the size and weight.

      Forget that, I want a smartphone with battery life that is measured in days instead of hours.

      • I'd choose 1/3rd the size and weight.

        Forget that, I want a smartphone with battery life that is measured in days instead of hours.

        We have that already. It's called the RAZR MAXX.

    • It'd also be a bomb. Hit it with a hammer, run. Energy dump.

      Also 'crushed' is not a nano-material. Could you imagine nano-granularized silicon?

      • by Jeng ( 926980 )

        I wonder if the TSA will start to not allow batteries that have a really high energy density?

      • by jbengt ( 874751 )

        Also 'crushed' is not a nano-material. Could you imagine nano-granularized silicon?

        They crushed nano-porous silicon. So TFA is about a nano-material.

    • Keep in mind they are saying triple the density of the anode, which is only half of the battery, so this is more like a potential for 1.5x improvement in overall battery size. SIlicon is also heavier by weight than the carbon, so this might mean minimal improvment in energy per weight.

  • by tp1024 ( 2409684 ) on Friday November 02, 2012 @01:56PM (#41856391)

    Breakthrough paradigm shifting innovative batteries have been around at least since 1901 and none of them worked.

    http://www.lowtechmagazine.com/2010/05/the-status-quo-of-electric-cars-better-batteries-same-range.html [lowtechmagazine.com]

    (ctrl+f -> miracle batteries)

    Technology changes incrementally and not on public demand.

    • by Anonymous Coward

      What a fucking stupid article. They inappropriately compare the "range" of a 1901 car with a top speed of 25 MPH and a Nissan Leaf with a far greater top speed.

      Nowhere in the article do they attempt to do the incredibly easy task of getting into a Nissan Leaf and driving it at a constant 25 MPH to determine its range at the same top speed of the 1901 car. As their own article states "driving faster uses more 'fuel'

  • my phone battery might last me past lunch some day?
  • I had read about the expansion phenomenon in the past. Does this mean that within every current Li-Ion battery there is a spongelike anode that is growing and shrinking in size whenever it charges? I don't think people realize that usually. Interesting.

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