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Friday, August 25, 2006

Safer Lithium-Ion Batteries

In light of Apple's and Dell's massive recalls, will computer makers opt for batteries that are less prone to catching fire?

By Kevin Bullis

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During a nail puncture test, a traditional lithium-ion battery bursts into flame. Safer battery materials, such as those used in a test by Valence Technology (right), prevent this from happening. (Credit: Valence Technology)

Yesterday's announcement by Apple that it is recalling more than one million lithium-ion laptop batteries sold in the U.S. is again throwing the spotlight on the safety of this battery chemistry.

Lithium-ion batteries are widely used in laptops, cell phones, and other mobile devices because of their ability to store lots of energy in a small, light package. But with a recent spate of incidents in which these batteries overheated or burst into flames -- prompting recalls of Sony batteries in Apple computers and more than four million Dell laptops -- many experts are questioning their safety.

A solution may be at hand, although it could mean accepting, for now at least, lower battery capacity. Safer materials for lithium-ion batteries already exist and are available in products such as power tools. With some modification, they could be used in laptops, and also help facilitate the widespread use of lithium-ion batteries in hybrid and electric vehicles.

Leading the way are two companies, A123Systems of Watertown, MA, and Valence Technology of Austin, Texas, which have designed lithium-ion batteries that avoid the traditional positive electrode materials used in most laptops and cell phones today.

According to Yet-Ming Chiang, materials science and engineering professor at MIT and a founder of A123, the cobalt-oxide or related oxide materials typically used in lithium-ion batteries become unstable if overcharged or overheated, which can happen in the case of battery damage or a fault in the manufacturing process that leads to an internal short. The unstable materials release oxygen, oxidizing other materials in the battery, which in turn produces more heat. The cycle continues in a process called "thermal runaway," which in some cases can lead to a violent explosion (see "Are Lithium-Ion Electric Cars Safe?").

In the new lithium-ion batteries, cobalt oxide is replaced with iron phosphate, a much more stable material. Indeed, a traditional lithium-ion battery will burst into flames in abuse tests, such as being pierced by a nail (see this A123 and this Valence video). But the new materials show little reaction at all.

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Comments

  • Airline Security
    joseparc on 08/25/2006 at 3:16 PM
    Posts:
    3
    After reading the article and watching the Valence video, I asked myself if I was going to feel safer the next time I got on an airplane knowing the guy on my left had to throw away his shampoo and toothpaste before he boarded but seeing the guy on my right still using his Dell laptop.
    Rate this comment: 12345
  • Market leaders Dell and Apple should collude in Safety!
    briang1621 on 08/25/2006 at 8:15 PM
    Posts:
    35
    Avg Rating:
    3/5
         Business collusion is illegal in the U.S., but safety collusion is not! Amazingly, the words “Lithium Ion” has a brand value to the public, but two of its larger computer distributors failed to catch the dysfunctional batteries which they placed in the open market.
            Together they have lowered the brand value of this still emerging product component, and likely hurt the other products brand value which dependent upon this component, like cell phones and other laptops. This can be seen in Qantas airline’s band of ALL Dell and Mac batteries in-flight use along with the massive recall of Apple’s Laptop batteries.
           But since neither of them exclusively owns the name “Lithium-Ion” why should they care?
    Collusion for safety standard is almost necessary for possibly dangerous emerging component or product categories, because as I put it “any one player in the game can kick the ball out of the field for everyone, and end the game.” 
    The brand name of “Lithium-Ion” is tarnished and it will take several months for the publics confident in this new component to come back. The lesson here is that for possibly dangerous emerging high tech components, safety infractions can hurt every company using that component, and that safety collusion for standard is the better than having someone else’s mistake affect your product.
    Ideally this can be done by enforcing safety testing to place a safety standard trademark on your component. Also, I see this as being a necessity in emerging markets like Robotics.
    Then again, “When the going gets hot, the hot ones logoff!”
    Brian Glassman
    http://www.smh.com.au/news/biztech/safety-first-for-carryon-dells/2006/08/23/1156012601607.html
    Rate this comment: 12345
  • Ironically
    roba on 08/27/2006 at 10:35 PM
    Posts:
    1
    The "solution" "found" by Chiang et al. was first brought to light by, I hate to tell you, the reseachers in Sony.  Olivines was suggested by Goodenough years ago but the first practical cell was made in Sony (yes the company which made explosive batteries) and published in 2001.  Thereafter did Chiang and gangs come to the scene,
    just to set the record straight.
    Rate this comment: 12345
  • laptop battery
    GreenApple123 on 08/31/2006 at 3:02 PM
    Posts:
    3
    Avg Rating:
    1/5
    i bought a laptop battery from http://www.laptopsforless.com/laptopbattery because mine woldn't even hold a charge anymore.  are replacement batteries, like the one i bought, safer or less safe than those produced by the major manufacturers?
    Rate this comment: 12345
  • Safer Lithium-Ion Batteries
    batterygirl on 12/05/2006 at 1:19 AM
    Posts:
    1
    Avg Rating:
    1/5
    if you want more knowledge about lithium ion battery,you can visit:http://www.lithium-batteries.net
    Rate this comment: 12345
  • Actual, Lithium-ion battery isn't very terrible.
    AlenJane on 05/09/2008 at 12:31 AM
    Posts:
    1
    Avg Rating:
    1/5
    Lithium-Ion batteries are longer lived than conventional batteries and do not require replacement as often. Commonly, it has internal circuit board with chips that allow it to communicate with the notebook to monitor battery performance, output voltage and temperature. It also gives the notebook much more accurate 'fuel gauge' capability to determine how much battery runtime is left before the next recharge is required. Actually, all the battery distributors know the importance of overcharge protection and overheat switch, so the issued lithium-ion batteries can be safely used.
    Rate this comment: 12345
  • Avoid danger
    toshiba on 07/13/2008 at 10:42 PM
    Posts:
    1
    Avg Rating:
    1/5
    What are the reasons that cause battery with no voltage or low voltage?

    No voltage.
    External shot circuit or overcharge, anti-charge
    Cells expansion and short circuit caused by direct anode contact and continuous high efficiency electric current overcharging.
    It can be avoided by:

    Checking if the battery is without voltage or electric current
    Avoiding short circuit
    Avoiding collision and pressure among batteries
    Charging the battery after it automatically powers off, then full charge the battery.
    Rate this comment: 12345
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