Elon Musk: Boeing 787 Dreamliner battery "fundamentally unsafe"


15 Responses to “Elon Musk: Boeing 787 Dreamliner battery "fundamentally unsafe"”

  1. mccrum says:

    Got it.  I can’t carry lithium batteries over a certain size on board the plane but they can pack them in around me without really thinking it through.

    If you’ll excuse me, I need to go buy as much Airbus stock as I can get my hands on.

    • Stooge says:

      The strange thing is is that this was thought through: Boeing had to jump through a fair few (though evidently not enough) hoops in order to persuade the FAA to allow the use Li-ion batteries.
      Stranger still, the weight saved compared to NiCads is only around 70lbs, or 0.02% of the plane’s weight, so it’s not as if this was a choice driven by necessity.

  2. Duffong says:

    Well, I’ve got to hand it to Elon, after all, he did have to get his batteries to fly before his car company could get off the ground. 

  3. Daneel says:

    I think Elon Musk has his head stuck in his “Fundament”.

  4. bcsizemo says:

    Well he is at least half right.  Packing li-ion cells in high density can lead to dangerous thermal situations.  Of course since li-ion cells require some type of microprocessor/controller to control their charging most have temperature monitoring built in.   So assuming the hardware is monitoring everything like it should be there wouldn’t be a thermal runaway.  Now a shorted cell causing excess current draw is an entirely different matter.

    • frank mcain says:

      A Failure Modes and Effects analysis is required to identify all failure modes that could lead to this potentially catastrophic event.  Thus a short shouls have been identified and mitigations provided.

  5. Eric0142 says:

    Interesting post on approaches to EV batteries taken by Tesla compared to other companies. Written by Rob Sweney, “Battery Wizard” at BRD Motorcycles.

    Seems to hit on the problem with the Boeing 787 that too much R&D was outsourced to the OEMs.


  6. Sigmund_Jung says:

    This reminds me of the delicate balance required by nuclear rods to avoid a meltdown.

  7. TinChicken says:

    You can read about the Tesla Roadster battery pack here : http://www.teslamotors.com/en_AU/node/3848
    It is an old post, but still accurate.

  8. Since large lithium batteries are a headache — if not inherently dangerous — we have to look at alternatives. One is to go back to the heavier nickel-cadmium batteries.
    Another is to use fuel cells. Fuel cells are now used in warehouse lifts and they supply unattended backup power to cell towers.
    Why not use them in commercial airplanes? They have proved reliable for over a decade in our space Shuttle.
    What about cost? With $16,000 for a lithium battery, cost is relative. Moreover, fuel cells are now a sixth of what they were five years ago.
    What about the Hindenburg?
    Those flames etched in our minds came from the fresh paint on the tarp. Hydrogen itself burns colorless, last about a second, and the flames go straight up.
    But where would we store the hydrogen? In tanks of the type now used in fuel cell cars — and they can be refilled every time the plane refuels.
    Or we could go with low pressure, though heavier, metal hydride tanks. This could eventually lead to our use of hydrides as artificial muscles — to operate the plane’s wings, brakes and landing gear. Metal hydrides can do this easily by us merely changing the current of the heating element inside the tank.

  9. frank mcain says:

    I agree with Musk, Boeing did not do a sufficient risk assessment when using this technology or forgoing the supplier management they had on previous aircraft. 

    These batteries interface with many other systems on the the aircraft and adds further complexity to debug. If the system was inherently safe, than Boeing should have been able to prove it by now – it has been almost a month and all Boeing can say is it will be fixed soon.

    Boeing has sucessfully convinced/badgered the FAA into agreeing to allow these batteries on the 787. The certification criteria of previous planes of it’s type was ammended with special conditions for these batteries.

     It is the first plane designed to have a fire, it just needs to be contained and vented.  I personally will never fly on an aircraft that was designed and approved to allow fires  in the foward and aft avionics bays..  This is a departure from previous FAA reguilations and certifications. 

    The hoops that the FAA put to allow the batteries on, were never jumped through correctly.  If they were this incident would not have taken place.Yes Musk may be grand standing a bit, however he is dead on with his assessment.

  10. dculberson says:

    This is battery science being done.  Unfortunately not quite enough of it got done before the product launch, but it will be sorted out and the items we personally use that have batteries will be the better for it. There are always problems with technological progress, overcoming the problems is what makes technology better.

    • frank mcain says:

      Aircraft is not supposed to be an Research and Development testbed.  Federal regulations 14CFR part 25 and FAA advisory circular 25-1309 require that the probablity of a catastropic event be less than 10 to -9.

    • drflorek says:

      Unfortunately they chose the wrong technology. They chose Lithium-ion Cobalt Oxide which is inherently more unstable. They should have chosen Lithium-ion Titanate which is much safer though more expensive and would require more cells. It is being used successfully by Proterra bus company and fielded successfully by Foothill Transit in Pamona Ca.

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