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Elon Musk  (Source: wired.com)
He offered his help to Boeing, but the company declined

Boeing's 787 Dreamliner jet has had a lot of troubles lately -- namely with its batteries -- and the last person the aerospace company likely wanted advice from was competitor Elon Musk.

Musk, the CEO of automaker Tesla and private space transport company SpaceX, recently told Flightglobal that the 787 Dreamliner's batteries are "inherently unsafe." His company SpaceX competes with the Boeing/Lockheed Martin partnership, United Launch Alliance, in the aerospace sector.

"Unfortunately, the pack architecture supplied to Boeing is inherently unsafe," said Musk.
"Large cells without enough space between them to isolate against the cell-to-cell thermal domino effect means it is simply a matter of time before there are more incidents of this nature. Moreover, when thermal runaway occurs with a big cell, a proportionately larger amount of energy is released and it is very difficult to prevent that energy from then heating up the neighboring cells and causing a domino effect that results in the entire pack catching fire."

However, Mike Sinnett, Boeing's 787 chief project engineer, defended the design and development of the batteries.

"I design a cell to not fail and then assume it will and then ask the next 'what-if' questions," said Sinnett. "And then I design the batteries that if there is a failure of one cell it won't propagate to another. And then I assume that I am wrong and that it will propagate to another and then I design the enclosure and the redundancy of the equipment to assume that all the cells are involved and the airplane needs to be able to play through that."

Musk's Tesla uses batteries fueled by lithium cobalt oxide, which is what Boeing uses for the 787. Musk understands that these batteries have highly flammable tendencies, and even offered his help to Boeing in its construction, but Boeing declined.

"They [Boeing] believe they have this under control, although I think there is a fundamental safety issue with the architecture of a pack with large cells," said Musk. "It is much harder to maintain an even temperature in a large cell, as the distance from the center of the cell to the edge is much greater, which increases the risk of thermal runaway."

In a recent report by The New York Times, it was discovered that Boeing knew about the battery fire issues in the 787 before this month's problems occurred, which grounded the jets in the U.S., Japan and India.

The report said that Japanese airline All Nippon Airways (ANA) replaced 10 787 batteries from May to December of 2012. Reasons included an unexpectedly low charge in the main battery, batteries that failed to start normally and one battery showing an error reading.

Japan Airline (JAL) also had "several cases" where it had to replace the 787's batteries before the issues that occurred this month, but it didn't disclose an exact number.

The airlines said they reported the incidents' to Boeing, but Boeing felt they didn't need to alert safety regulators because it was not considered a safety issue, but rather "within the scope of regular maintenance" carried out by airline crews.

It was also recently discovered that the Japanese government loosened safety regulations for the 787 Dreamliner back in 2008 in an effort to speed up the aircraft's deployment within the country.

Source: Flightglobal



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RE: Read The Article
By captainBOB on 2/1/2013 9:40:24 PM , Rating: 2
Doing reasonably well for building a car company up from the ground, a feat the US hasn't seen in over half a century. They actually have a car, and haven't been Tuckered out just yet. Being in the red consistently at this stage is not unexpected, it takes a lot of capital to even get off the ground and the Model S only began production in Summer 2012.

As for the rest of your post, I can only guess that you suspect an ulterior motive behind all this. Which is valid, some theories suggest he is trying to show Boeing how good his battery tech is in the hope that that Boeing may buy their battery tech, a lucrative source of income if there ever was one.

Public defecation? Really?


RE: Read The Article
By fteoath64 on 2/4/2013 10:55:23 AM , Rating: 2
You are right!. Elon's people have more experience designing these battery systems than Boeing (about 10X as much) and still not a single case of a fire. The forces on those batteries in a car is far more than in an airline. In fact planes has natural cooling while a car needs seriously engineered cooling management to work those batteries properly or else they age pre-maturely or burst into flames.
Boeing will not listen. They just plot on with their bureaucratic rules eventually make a better battery to have that fail a year or two later ...


RE: Read The Article
By Arc177 on 2/5/2013 11:04:51 AM , Rating: 2
Your statement is patent nonsense. Boeing has a vast and rich history of designing and implementing Li Battery systems in thousands of aerospace systems, probably more. Unfortunately experience does not lead to a robust design every time, it only theoretically improves your odds of success. Your statement that cars undergo greater vibrational environments is laughable as well as your statement about the cooling environment. One can only make the inference that your statement is made out of ignorance.
Ultimately, somewhere this is a Systems Engineer failure- as previously mentioned the FMEA was incomplete possibly or some interface definition and testing was not properly done and the end result are what some people call "design features". These "features" are unintended consequences that show up in large complex systems. It is also common at the beginning of a new products functional lifecycle to see the highest number of engineering design changes.


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