Follow Slashdot stories on Twitter


Forgot your password?
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."
This discussion has been archived. No new comments can be posted.

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

Comments Filter:
  • by frovingslosh ( 582462 ) on Friday November 02, 2012 @02:38PM (#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 mlts ( 1038732 ) on Friday November 02, 2012 @03:09PM (#41856615)

    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 flooded wet cell, I'd just need a battery that weighed less than an ounce.

    However, the big issue is energy stored per volume. Weight is one thing, but if we can get energy stored per volume even within an order of magnitude of gasoline, the game changes completely:

    We can get rid of internal combustion engines completely for electric motors which do not have major energy losses due to exhaust and heat. Electric motors also have peak torque at 0 RPM.

    Areas where fuel is wasted due to idling will be eliminated. A stopped electric vehicle only needs juice to keep the occupants comfortable and the computer systems going. The drivetrain needs no power unlike a gas or diesel engine which has to keep at a certain RPM level (unless stopped and started.)

    Solar would become a lot more useful because there would be the ability to store that energy for use at night.

  • by Githaron ( 2462596 ) on Friday November 02, 2012 @03:11PM (#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.

  • by Guspaz ( 556486 ) on Friday November 02, 2012 @03:38PM (#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 Guspaz ( 556486 ) on Friday November 02, 2012 @03:40PM (#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.

Comparing information and knowledge is like asking whether the fatness of a pig is more or less green than the designated hitter rule." -- David Guaspari