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Carbon Nanotube Batteries Pack More Punch

Posted by CmdrTaco on from the coast-to-coast-at-most dept.

cremeglace writes "Researchers at MIT have come up with a new way of making batteries from carbon nanotubes. Carbon nanotubes are attractive materials for battery-making because of their high surface area, which can accept more positive ions and potentially last longer than conventional batteries. Instead of this design, the MIT researchers introduced something new — using chemically modified carbon nanotubes as the positive ion source themselves. For now, the new batteries can power only small devices, but if the method can be scaled up, the batteries may provide the power needed for applications like electric cars."

5 of 163 comments (clear)

  1. Have they figured out the safety aspect? by jeffmeden · · Score: 4, Interesting

    Will they be able to prevent thermal runaway in these better than in, say Lithium based batteries? As density goes up this needs to be more of a concern. Laptops melting down are one thing, but imagine the havoc of a car exploding due to battery failure. That's the last thing the electric car movement needs to have happen.

    1. Re:Have they figured out the safety aspect? by IflyRC · · Score: 4, Interesting

      I fly a lot of R/C models ranging from turbines to electric powered helicopters. The chemistry in the batteries has changed over the years but the highest output batteries right now are lithium polymer. Now, there are some A123 type batteries that are better and getting better but most of the extremely high powered aircraft right now use Li-Po. Battery failures can be caused by several things but what alarms me about putting something like this in a vehicle is the hazard of fire in the even of an automobile accident. When you have a high impact with some of these batteries and a cell is ruptured - the packs begin to puff - then vent. When they vent, the heat is thousands of degrees which will set off other cells in the pack. Think of the old stories about exploding gas tanks in the event of a car crash. Now think of all of these batteries packed into tight places under trunks and back seats and getting rear-ended or even just a cell going bad...or the balancer in the charger going out and overcharging a cell causing failure in that cell. A failed charger can cost you your entire car...or better yet, your house. Think of this thing going up in the garage...and you having a gas water heater installed out there. This stuff is dangerous enough as it is right now.

    2. Re:Have they figured out the safety aspect? by jeffmeden · · Score: 4, Interesting

      But, "uh oh", these batteries still use Lithium! They simply have a new way of producing the electrode: "The result was a highly porous carbon nanotube electrode with lots of oxygens exposed on the surface, ready to bind with lithium."

      Also, there is nothing inherently tragic about Lithium; any technology that stores and releases energy can fall prey to thermal runaway. In the highly-available-power world in which I work, we have seen lead acid batteries go into thermal runaway after particular amounts of abuse (or defective manufacturing/installation).

      As someone who has used/abused lithium polymer batteries in the RC world (similar to the other respondent) I have seen what can easily happen to high-energy batteries when they are improperly maintained. The question is, what happens when there are hundreds of millions of these packs in cars all across the US, being put through various amounts of abuse? They will fail, and we need a safety mechanism that is highly reliable (like a re-enforced steel shell that can vent hot gases away).

      The comparison to a gas tank is somewhat inadequate as these batteries are far heavier than gasoline; if you have a serious accident that compromises the frame of the car you really can't guarantee that the battery container is going to be unperturbed. There needs to be two or more dedicated safety measures to contain or divert the energy from the batteries away from the occupants in the event of damage.

  2. Re:Sometimes it's more mundane by Avtuunaaja · · Score: 5, Interesting

    Everybody knows that if you can design an economically viable improvement on present-day batteries, you are going to be wildly, obscenely rich. There are plenty of applications where people would be perfectly willing to pay several times more for a battery than what they are paying now if there was a significant improvement in capacity/mass. This leads to a lot of research being concentrated even on very wild potential ideas. Many are viable in the lab, but are too expensive to produce (by a margin of several orders of magnitude), too dangerous, too short-lived, or any combination thereof.

    No matter how many misses there will be, this situation is more or less the ideal case for a free market to optimize for -- if it is possible to safely store more electrical energy in a smaller mass, it will be found eventually.

  3. At least they don't promise "12 month" deployement by sirwired · · Score: 4, Interesting

    Unlike the fuel cell guys, which are constantly promising consumer products shipping in "just a few months", I'm glad these folks realize their work is still well away from widespread application where it's really needed.