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Elon Musk: Boeing 787 battery fundamentally unsafe

flightglobal.com

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Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#41

Post by rosser »

meh01 wrote: post #30
grinich wrote: post #16

Earlier quoted context omitted.

Not just any MIT prof-- Sadoway is an expert metallurgist and leading researcher on energy storage in batteries. The article is also incorrect: Sadoway is part of the Materials Science Engineering Department. As an aside, his intro chemistry lectures are excellent, entertaining, and available online. http://ocw.mit.edu/courses/materials-science-and-engineering...

Except they're both clueless about battery use in planes.

...and on what basis do you make that claim?

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#43

Post by sp332 »

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.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#44

Post by coryrc »

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 a meltdown like the more active chemistries.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#46

Post by gvb »

avelis wrote: post #5
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.

It would appear that Boeing had a small oversight. Building a plane is not like building a car. There are different requirements. While some requirements overlap there are clear fundamental differences. Now, with that said, it could be that SpaceX and Tesla were allowed to focus more on batteries while Boeing had to improve jet engine efficiency as well as electrical battery usage.

Pedantic: Boeing subcontracted the jet engine efficiency improvements to Rolls-Royce (Trent 1000) and GE (GEnx).

http://en.wikipedia.org/wiki/Rolls-Royce_Trent_1000

http://en.wikipedia.org/wiki/General_Electric_GEnx

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#47

Post by rpm4321 »

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…

"I'm saying this because he is a businessman, not an engineer."

Musk is the Chief Designer at Space-X, Product Architect at Tesla Motors, and a member of the Stanford University Engineering Advisory Board. He has previously served as a member of the United States National Academy of Sciences Aeronautics and Space Engineering Board. - Wikipedia.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#48

Post by lostlogin »

Evbn wrote: post #32
CamperBob2 wrote: post #28

Earlier quoted context omitted.

If no, what is the requirement? Masters or PhD Launching payloads to the ISS is good enough for me.

That was done by Musks company, not Musk alone.

There aren't many achievements that are truly solo efforts - there is usually someone keeping the home fires burning at the very least.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#49

Post by jonknee »

Evbn wrote: post #36
sfall wrote: post #13

Earlier quoted context omitted.

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

Which covers 0 information about Li battery vs other kinds, especially considering when he earned his Bachelor's.

Then there's that small matter of his founding an electric car company that uses Lithium Ion batteries. Oh and the rocket company. I can't imagine many people more qualified to talk about LiIon and aerospace.

Re: Elon Musk: Boeing 787 battery fundamentally unsafe

#50

Post by AngryParsley »

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?

Quick, get ahold of the engineers at Boeing! Tell them to switch to whatever they used on their older planes! Surely they haven't considered that idea yet!

Have you ever been in a situation where a manager proposes a technical solution that everyone else has already dismissed as preposterous? Now you know how it feels to be on the other side of that.

With that mockery out of the way, I'll give my understanding of the situation: The lithium ion batteries on the 787 are much smaller and lighter than their predecessors. They also take up less space and require different input and output voltages and currents. They have different charging profiles. Swapping them out with an older battery technology is infeasible. It would require redesigning other components to make room, building new transformers and voltage regulators, and writing new software to charge the batteries safely. It would also reduce the range, capacity, and/or efficiency of the 787.

I do apologize if I went overboard with the mockery. Please don't take it personally; it's fun to write.

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