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Elon Musk: Boeing 787 battery fundamentally unsafe

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Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#51

Post by jonknee »

djt wrote: post #8
garretruh wrote: post #2

While I have enormous respect for Elon Musk, I would hope that Boeing engineers have just as thorough an understanding of the workings and safety implications of Lithium-ion batteries. Though Tesla's engineering is admittedly much more focused around battery technology, Boeing has decades of experience with aircraft electrical systems.

no doubt Boeing know that even if the batteries smoke and fail they wont be a threat to safety, but Musk has a better handle on marketing. If there is smoke on a plane or car people expect the worst, regardless of if it is actually a safety issue.

The batteries actually went up in flames though, it wasn't just smoke (I'm recalling the the adage about where there's smoke there's fire). The new flagship plane from Boeing wasn't grounded worldwide because there was no threat to safety.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#52

Post by lostlogin »

sp332 wrote: post #43
backprojection wrote: post #29

So what's the motivation for using these batteries in the 787 anyway? Can they just switch to whatever they've used before?

The new engine requires much higher-capacity batteries to start them. A battery with the old tech would be huge and heavy. The new battery technology is much lighter than the old ones.

That's interesting - why are the batteries onboard and not ground equipment? Obviously restarting a stalled engine would be handy, but is this something that actually happens? And if it is, couldn't the running jets provide the power somehow? I seem to remember that some old WW2 prop aircraft had ground equipment requirements to start them from cold (power or warmed air or something?) Obviously this isn't an area I know about but I am curious about it. Thanks.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#53

Post by gee_totes »

sp332 wrote: post #43
backprojection wrote: post #29

So what's the motivation for using these batteries in the 787 anyway? Can they just switch to whatever they've used before?

The new engine requires much higher-capacity batteries to start them. A battery with the old tech would be huge and heavy. The new battery technology is much lighter than the old ones.

Do you know if there's anything unique about the electrical system that would cause a greater load than a comparable aircraft?

I'm thinking high-tech radar, wifi, photon torpedoes, etc.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#54

Post by bigiain »

coryrc wrote: post #44
Camillo wrote: post #3

This is a very smart move by Musk from a PR point of view. By accusing Boeing's batteries of being fundamentally unsafe, he garners the maximum amount of trust from people who are concerned about battery safety, so that, when he immediately follows up with an explanation of why this couldn't happen on a Tesla, those very people are already leaning towards believing him. This goes over much better than attempting to d…

Tesla's /cells/ are also "fundamentally unsafe", but they make the /batteries/ as safe as possible. Fundamentally _safe_ would be LiFePO4 chemistry: http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery Longer lifespan and significantly cheaper than cobalt, manganese, etc; but 20% lower specific mass. Survives having a nail driven through a fully-charged cell with only some smoke and a small bit of flame -- not…

"Tesla's /cells/ are also "fundamentally unsafe", but they make the /batteries/ as safe as possible."

While it's certainly true that the Li-ion chemistry used in the Tesla's batteries are flammable, keep in mind the current common alternative to those potentially burning cells is carrying round a metal or plastic tank with 10 or more gallons of gasoline in it. If there weren't a 100+ year history of people doing just that and getting away with it most of the time, you surely wouldn't be allowed to do it in today's safety-conscious society.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#55

Post by joezydeco »

geekylucas wrote: post #35
djt wrote: post #8

Earlier quoted context omitted.

no doubt Boeing know that even if the batteries smoke and fail they wont be a threat to safety, but Musk has a better handle on marketing. If there is smoke on a plane or car people expect the worst, regardless of if it is actually a safety issue.

Li-ion fires tend to generate oxygen and so they are quite hard to put out. At 30,000 ft in the air I would consider this a fairly significant threat to safety.

Lot of shipping companies won't even handle Lithium batteries (over a certain size or quantity) on their flights.

FedEx's shipping guide, as an example: http://www.fedex.com/downloads/shared/packagingtips/battery_...

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#57

Post by chernevik »

garretruh wrote: post #2

While I have enormous respect for Elon Musk, I would hope that Boeing engineers have just as thorough an understanding of the workings and safety implications of Lithium-ion batteries. Though Tesla's engineering is admittedly much more focused around battery technology, Boeing has decades of experience with aircraft electrical systems.

I shouldn't be surprised if there aren't several people within Boeing with exactly the right expertise. Whether they were identified and listened to by management is a separate question.

If Musk is right (IANA Battery Guy), I would presume there are cost / design trade-offs involved. And some exec had to evaluate those against safety issues. Those are engineering decisions, they're also business decisions. If the execs deciding that didn't have the proper background to make an engineering evaluation himself, they are left trying to decide which engineers to trust. It isn't at all hard to see someone getting that wrong.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#58

Post by MaysonL »

michaelkscott wrote: post #19
richardjordan wrote: post #14

Earlier quoted context omitted.

My understanding is that Elon Musk, a physicist by education, is indeed an engineer and was very hands on in the engineering processes at SpaceX, so I'd assume he wasn't out of the technical loop that led to design decisions at Tesla.

Maybe a little OT but: Can you be considered an "ist" by having just a BS degree. That is, physicist, computer scientist, etc... If no, what is the requirement? Masters or PhD?

Go look up Ed Fredkin or Amory Lovins.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#59

Post by neurotech1 »

gee_totes wrote: post #53
sp332 wrote: post #43

Earlier quoted context omitted.

The new engine requires much higher-capacity batteries to start them. A battery with the old tech would be huge and heavy. The new battery technology is much lighter than the old ones.

Do you know if there's anything unique about the electrical system that would cause a greater load than a comparable aircraft? I'm thinking high-tech radar, wifi, photon torpedoes, etc.

No bleed air from the engines. Pressurization, hydraulic actuators, air conditioning and accessories are all electrical. That uses 1.45MW on a 787

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#60

Post by digikata »

sfall wrote: post #13
eduardordm wrote: post #9

Elon seems to really want to get involved in this. Make no mistake, Boeing and SpaceX are fierce competitors for government contracts with very dubious selection processes. I'm saying this because he is a businessman, not an engineer. He seems to be getting a lot of information about the 787s batteries inner workings when the number of airplanes and suppliers are very limited. Edit: I'm not trying to be cynical, but…

while not a PE he is no slouch, he has a bachelor's in physics

Is a Professional Engineer certification relevant here? All the PEs I've met work in the civil engineering field.
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