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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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Me too
By Motoman on 1/30/2013 12:53:16 PM , Rating: 3
Yeah, I offered to help them too...at only half of Musk's hourly rate. They turned me down to...arrogant bastards.




RE: Me too
By GulWestfale on 1/30/2013 1:01:29 PM , Rating: 3
i once made a paper airplane in class, but NASA won't even return my calls...

i heard on a news site that japanese investigators say that the batteries are absolutely OK, but that the fault likely lies in somewhere else in the electrical system, possibly voltage regulation.


RE: Me too
By Lonyo on 1/30/2013 1:41:46 PM , Rating: 5
The batteries themselves may not be causing the problem, but if something else causes a problem and the batteries are unable to handle it, that is a problem with the battery.

From a safety perspective, no matter where the fault is, other (reliant) elements should be able to handle the issue rather than causing other additional issues, such as overheating.


RE: Me too
By Shig on 1/30/2013 2:04:18 PM , Rating: 3
It's not like Elon Musk builds on of the most advanced electric power trains available and is also CEO of the first private company to launch a rocket to the ISS, oh wait.......................

Motoman = Rush Limbaugh of Dailytech. Spewing troll hate is easy bro, learn to cite a fact.


RE: Me too
By othercents on 1/30/2013 3:38:58 PM , Rating: 3
You also have other well know battery consultants saying the same things.

quote:
“As the size of the cell increases, the chance of something happening increases because you have an increased amount of material being exposed” says Dr. K.M. Abraham. “[Lithium-ion batteries] are not as forgiving as far as design and construction are concerned. If you have quality control issues, it can be very bad.”

Dr. Abraham is a battery consultant and professor at Northeastern University in Boston and has been researching lithium-ion batteries since 1976.


There is still an option for overcharging a single cell within one of the batteries even if the battery never hit peak charge.


RE: Me too
By FaaR on 1/31/2013 5:46:41 AM , Rating: 1
quote:
There is still an option for overcharging a single cell within one of the batteries even if the battery never hit peak charge.

...Possibly, yes. As in, anything can happen. However, Li-ion batteries should have on-board electronics to control and measure the charging of each individual cell, to prevent just what you describe. Batteries in modern laptop computers and tablets work this way for example.

It's possible this regulation hardware failed somehow, but if that can happen and the battery can still be charged without any monitoring safeties then someone screwed up.


RE: Me too
By othercents on 1/31/2013 8:25:19 AM , Rating: 4
quote:
However, Li-ion batteries should have on-board electronics to control and measure the charging of each individual cell, to prevent just what you describe.

No they don't since a single Li-ion battery consists of multiple cells with insulation between them all wired to the battery terminal. The electronics are what control the charge on the battery (or in the case of the 787, 8 batteries), but not individual cells within the battery. It is very possible for a single cell to overcharge while the battery as a whole never hits peak. This is best illustrated from GSYuasa design spec.

http://www.s399157097.onlinehome.us/SpecSheets/LVP...

You can also read more about what Dr Abraham has to say about overcharging a single cell within a Li-ion battery here:

http://www.wired.com/autopia/2013/01/boeing-787-in...

Other


RE: Me too
By DockScience on 2/2/2013 4:35:21 PM , Rating: 2
Musk is right on target, A WELL designed high power lithium battery WILL have monitoring of charge/discharge of individual cells. And in a fire critical installation, they will also have heat removal system capable of removing the heat to stop a thermal runaway, preventing catastrophic failure/rupture and solvent fires.

The question is whether or not the 787 battery is such a well designed battery, or is lacking.

I don't see heat pipes, liquid exchangers or other beefy heat removal devices in the pictures... and that's not a good sign for a battery which can withstand a thermal runaway initiation.


RE: Me too
By Jeffk464 on 1/30/2013 6:27:50 PM , Rating: 1
Yup, if this guys was working at Boeing he would probably be the smartest guy there, and that's saying a lot.


RE: Me too
By Mint on 1/30/2013 7:38:06 PM , Rating: 3
Am I the only one that sees Motoman's post is dripping with sarcasm?

Between you, the people that rec'd your post, and Pirks, I think the DT community is running a bit dry in its sense of humor...

(I don't agree with Motoman much, but geez, he's just making a joke here)


RE: Me too
By VeauX on 1/30/2013 3:28:27 PM , Rating: 2
Sounds like someone didn't do his D/P-FMEA homework correctly...


RE: Me too
By johnsmith9875 on 2/4/2013 9:28:10 PM , Rating: 2
I suspect Boeing has a flawed charging circuit. Yuasa may not be at fault here.


RE: Me too
By Jeffk464 on 1/30/2013 6:26:04 PM , Rating: 2
quote:
i heard on a news site that japanese investigators say that the batteries are absolutely OK, but that the fault likely lies in somewhere else in the electrical system, possibly voltage regulation.


Lol, yup first rule of support, blame somebody else.


RE: Me too
By FaaR on 1/31/2013 5:48:50 AM , Rating: 2
Incidentally, the company that builds these batteries is japanese. ...Coincidence? Well, you decide. ;)


RE: Me too
By Jeffk464 on 1/31/2013 11:43:36 AM , Rating: 2
no, I don't get the connection


RE: Me too
By geddarkstorm on 1/30/2013 3:13:20 PM , Rating: 2
Well, Boeing is sure going to lose a lot more money now than it would have if it had listened to Musk.


RE: Me too
By Pirks on 1/30/13, Rating: -1
RE: Me too
By Bateluer on 1/31/2013 3:50:18 PM , Rating: 1
Your sarcasm detector needs new batteries.


RE: Me too
By sorry dog on 2/4/2013 10:44:58 PM , Rating: 2
Easy for you to say but since his detector is an Apple...he has to send to back to the manufacturer.


By Kafantaris on 1/30/2013 3:34:37 PM , Rating: 2
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.
http://spaceflight.nasa.gov/shuttle/reference/shut...
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 goes 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.
http://news.discovery.com/tech/biotechnology/artif...




By Stan11003 on 1/30/2013 4:09:56 PM , Rating: 2
The battery in question is actually used just like your car battery to start one of the planes auxiliary motors. That needs a lot power in an instant. I'm not sure fuel cells would be right for this application.


By Jeffk464 on 1/30/2013 6:40:07 PM , Rating: 3
I was a helicopter mechanic for 6 years and our system used a much safer hydraulic starter. Sometimes low tech is the answer, or why not just plug in a ground cart start the engines. This is all pretty standard stuff and a whole lot cheaper.


By Jeffk464 on 1/30/2013 6:44:33 PM , Rating: 2
argh

ground cart to start the engines

F15's and 16's cant be started without ground equipment, its really not a big deal.


By GreenEnvt on 1/30/2013 10:37:46 PM , Rating: 2
Great in most cases, but then the plane is limited to airports with that infrastructure.

Also, then you are f'd when the engines shut down in flight and you want to restart them. There have been several cases where hundreds of lives were saved because the engines could be restarted in flight after a failure.


By Jeffk464 on 1/31/2013 12:12:08 AM , Rating: 2
Ram air, you use the forward motion of the plane to get the engines spooling up to starting speeds. If the plane hasn't fallen out of the sky its engines are no doubt already spinning up to speed. If I remember right you only have to spool them up to about 30% of their operating speed to get them started.


By sorry dog on 2/4/2013 11:12:20 PM , Rating: 2
The minimum speed required for a windmill start maybe (and probably is) quite a bit higher than the best glide speed.

...and parameter for one engine operation may leave a narrow margin for windmill start of the other engine.

Regardless...the batteries are not used to start the main engines. They are used to start the APU and provide emergency power to things needed at all times like flight controls and high tech computerized glass cockpit in 787 (that would probably take 10 minutes to reboot is power were disrupted). Once the APU is running, an 1100 HP Sunstrand unit in the 787, then that can start the starter/generators on the main turbines.

Of course it was the batteries for the APU that had problems in one the JAL flights....


By sorry dog on 2/4/2013 10:50:04 PM , Rating: 2
Not a big deal in the F16....until you have to pump the hydraulic accumulator 300 times for one shot at the restart...


By FaaR on 1/31/2013 5:53:33 AM , Rating: 2
IIRC the dreamliner carries a 500MW powerplant, if a completely safe helicopter hydraulic starter could have spooled that thing up to speed I'm sure boeing would have chucked it in their design. It's probably not possible though, or at least not within weight limits.

Hence, badass but finicky batteries.


By Jeffk464 on 1/30/2013 6:36:38 PM , Rating: 2
quote:
Hydrogen itself burns colorless, last about a second, and the flames goes straight up.


I'm sure the passengers on the Hindenburg would have felt better if the flames didn't have any added color. :)


By ritualm on 1/30/2013 8:09:37 PM , Rating: 2
Except the fuel cell design in the Space Shuttle does double-duty. Very simple chemistry formula:

2 H2 + O2 -> energy + 2 H2O

In the Space Shuttle, the fuel cells create both the electric power needed to run its onboard systems, and drinkable water for its crew. Thus the fuel cells make sense.

Now, put that into a 787. Sure, you'll have the power you need, but what are you going to do with the water byproduct? Let's not forget the safety precautions needed to ensure that the hydrogen tank doesn't leak. Those lithium batteries fail and catch fire are bad? If an H2 tank leaks, the whole thing explodes - it's worse than using C4 as the 787's primary insulation material.


By FaaR on 1/31/2013 5:58:18 AM , Rating: 2
You may want to know, there's a lot of hydrogen in jet fuel, being a hydrocarbon and all... :P

A catalyst/reaction chamber can break down the fuel to release hydrogen for use in the fuel cell, or at least crack the hydrocarbon chain to a shorter form that can be used in a fuel cell. Some cells are designed to run on methane I believe.


By AnnihilatorX on 2/2/2013 8:47:13 AM , Rating: 2
You can vent the water vapor out to the atmosphere. I mean, burning jet fuel also gives H20, where do those go? Same logic

As to power requirement, couple fuel cells with super capacitors I can see power spike requirements not an issue.


By mrwassman on 1/30/2013 11:12:50 PM , Rating: 2
Nickel Cadmium? Are you joking? Maybe NiMH.


By Pneumothorax on 1/31/2013 5:55:01 AM , Rating: 2
Why even nimh? Lithium phosphate is almost just as safe as nimh with almost the same power/weight density as lithium ion/cobalt. Even with these potentially explosive batteries that many modern laptop still use, a properly designed charging circuit for these would include individual cell voltage/temp monitoring, should be catching these overheating/overcharging cells, and cutting off the charge before the heat up and explode. Somehow, these batteries are either outright defective or are being overcharged.


By Amiga500 on 1/31/2013 12:23:36 PM , Rating: 2
Boeing and Airbus have been working on that for some time now.


Grain of salt
By rangerdavid on 1/30/13, Rating: 0
RE: Grain of salt
By rangerdavid on 1/30/2013 2:37:26 PM , Rating: 3

ALSO, he's just trash-talking his competition, big time. To be taken with a LARGE grain of salt.


RE: Grain of salt
By geddarkstorm on 1/30/2013 3:18:35 PM , Rating: 4
The fact Tesla cars aren't bursting into flames (or having to be replaced far too often as the article says) like 787 batteries seems to be all the proof we need. Obviously Musk -- an expert in this technology -- knows enough about the 787 battery, and if the issue he sees is a fundamental one of the physics and chemistry, then no other specifics are necessary.


RE: Grain of salt
By Jeffk464 on 1/30/2013 6:31:21 PM , Rating: 2
He has also managed to put the only successful electric cars on the road and so far the only successful private enterprise to not only launch into orbit but also dock with the space station. I don't think anybody should really blow off his advice.


RE: Grain of salt
By sorry dog on 2/5/2013 12:39:08 AM , Rating: 2
...and maybe Boeing should just drop a press release saying they would be more than willing to help, for a modest fee of course, with the brake failure problems that have hindered Telsa Roadster in the past (for instance on the Top Gear test track).


RE: Grain of salt
By othercents on 1/30/2013 3:23:16 PM , Rating: 1
Is this enough information?

http://www.s399157097.onlinehome.us/SpecSheets/LVP...

You can see the configuration of the actual batteries here.

http://www.wired.com/images_blogs/autopia/2013/01/...

I think the idea is that there isn't enough insulated separation between the packs to keep them from having a domino effect and there isn't enough cooling to cool each pack individually.

However the statement from Boeing saying that they designed them not to fail, so there isn't a reason to design safe insulation between the packs is ludicrous. Lithium batteries are inherently unsafe and all possible safety precautions should be taken.

Other


RE: Grain of salt
By Jeffk464 on 1/30/2013 6:33:34 PM , Rating: 2
quote:
Lithium batteries are inherently unsafe


Kind of makes me think they don't belong on commercial passenger planes period.


RE: Grain of salt
By Adul on 1/31/2013 12:19:11 AM , Rating: 2
There are other Lithium chemistries that are much safer than what Boeing has decided to go with. Lithium iron phosphate for instance would be a better choice.


RE: Grain of salt
By theapparition on 1/31/2013 10:03:08 AM , Rating: 3
quote:
However the statement from Boeing saying that they designed them not to fail, so there isn't a reason to design safe insulation between the packs is ludicrous.

That is not at all what the Boeing designer said.

"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."

Emphasis added. Clearly you stopped reading after the first few words.


RE: Grain of salt
By sorry dog on 2/5/2013 1:16:26 AM , Rating: 2
Good find on the pictures, but the picture of the battery cell/pack in the brochure looks quite a bit different than those pictured good bad picture.

In fact, I guess the circuit board in the case monitors each cell as you can see larger lugs and wires for the pack series and pos/neg terminals, but you can also see smaller ones as well going from each cell to the plug socket on the circuit board.

It likely monitors charge/discharge rates and voltage for each cell, but the question is if each of the cells have a thermal monitor as well...or if it did, was the controller board able to shut the whole pack down in time before the cell got hot enough to short circuit.


Read The Article
By spazmedia on 1/30/2013 2:41:47 PM , Rating: 3
If anyone would bother to read the article, what Mr. Musk stated was confirmed by a professor from MIT.




RE: Read The Article
By superflex on 1/30/13, Rating: -1
RE: Read The Article
By captainBOB on 1/31/2013 8:54:50 PM , Rating: 2
quote:
Elon Musk …….paid for by the taxpayers.


Except that unlike a lot of other "green" investments the government has made (and lost big on), Tesla has real, tangible results.

The Model S is a real car and its on sale right now, I've seen it in person, and quite frankly, if Tesla's plans continue to completion, they will effectively iPhone the car industry, the Model S sets the bar for what a car can be to a whole new level and puts the other EV solutions from the major players to complete shame.

They expect to turn a profit for the first time this quarter, now that the majority of their capital expenditures to get the manufacturing plant up to speed is done.

They are building (read: building, not planning to build) a supercharger network across the US (and later on the rest of the world) so that Tesla owners can travel across the country without worrying about range. There are 6+ in operation as of this minute. Supercharger stations are free of charge to Tesla owners.

As a taxpayer, this is one investment that I am quite happy about, its amazing what having actual results can do for your company, who'd have thunk it?


RE: Read The Article
By Tumbleweedy on 2/1/2013 2:17:23 AM , Rating: 2
Really? OK. How's Elon doing on funding for Tesla? Could he be running low? Maybe? If he is, could extra publicity hurt? What on earth is the news value of Elon sending an email to FlightGlobal? Seriously, I want to go to Bellevue Square and do number 2 in the middle of the Tesla showroom.


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.


Yeah, and we all see how THAT worked out....
By rdhood on 1/30/2013 1:50:48 PM , Rating: 2
quote:
"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."


FAIL! First, there WAS a failure. Second, it DID propagate to other cells. At least the airplane was able to "play through that"




By geddarkstorm on 1/30/2013 3:19:58 PM , Rating: 2
Do have to give them props for that! Despite the failures, the aircraft made it to safety just fine, and the fire didn't seem to spread throughout the whole craft. That containment of the battery fires is indeed excellent engineering.


RE: Yeah, and we all see how THAT worked out....
By othercents on 1/30/2013 3:27:39 PM , Rating: 2
quote:
Do have to give them props for that! Despite the failures, the aircraft made it to safety just fine, and the fire didn't seem to spread throughout the whole craft. That containment of the battery fires is indeed excellent engineering.

I don't agree since there was fire damage around the area the batteries were located.

http://www.wired.com/images_blogs/autopia/2013/01/...

Other


By geddarkstorm on 1/30/2013 11:18:21 PM , Rating: 2
Have to admit, that picture is kinda scary.


Nothing to see here ...
By CityZen on 1/30/2013 2:09:49 PM , Rating: 2
quote:
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.

I suspect that for Boeing anything less severe than the wings falling off in mid air would be classified as "within the scope of regular maintenance"




Public Relations Nightmare Indeed
By Keeir on 1/30/2013 3:17:22 PM , Rating: 2
This is quickly becoming a real problem for Boeing. Everyday that passes without a plan or cause just makes it worse and worse. Boeing needs to ASAP declare

1.). They are designing a new "safer" battery and give an estimate when it will be ready

2.). They have a proposed plan on returning the 787 to the sky in the interim (even if it means removing each battery before flight and putting it in freezer!)

I understand the Japanese supplier wouldn't admit the battery is unsafe and Boeing would not want to place the blame directly on a Japanese supplier give who has ordered the 787, but as time passes more people like Elon Musk will come out of the woodwork and offer random suggestions which makes Boeing appear more and more foolish




By drycrust3 on 1/30/2013 8:15:05 PM , Rating: 2
quote:
"I design a cell to not fail and then assume it will and then ask the next 'what-if' questions," said Sinnett.

If you look at the battery box some of the blue paint has been chipped away leaving the grey primer showing almost exactly in the middle of where the heat discolouration is, just as though someone accidentally gave the battery box "a bit of a tap" with their steel capped boots.
http://images.dailytech.com/nimage/29288_large_jal...




Musk is right.
By mugiebahar on 1/30/2013 8:33:49 PM , Rating: 2
Musk is 100% correct. The thermal problems encountered by the use of lithium batteries with Cobalt electrodes is very unstable in that situation. The problem is in different parts of the design as well. Musk is right the fact they are too close to prevent thermal issues, but also in the way they charge the batteries as well. They expect the charge to be anywhere from 75-80% charge in about 80mins. BIG problem, you go from operating temp of around 60 degrees to 140 degrees in such a short time thermally you propagated the temp by x amount too fast. Cobalt at that temp becomes unstable.. Now with no real cooling solution and the close proximity of the cells not allowing heat to dissipate, it's not logical to think something wont get out of hand. I hate engineers who are so pompous that they can't realize they made a mistake. You give us a very bad name. The engineers of the 60's and 70's were so much better then nowadays. They actually knew what they were doing. You make me ashamed @ times to be an engineer. It's so logical your faults In your design and yet you stupidly ignore facts.




Tesla
By btc909 on 1/31/2013 2:39:58 AM , Rating: 2
Musk was right well before what was going to happen with the Fisker cars catching fire and low and behold they did. I don't know of a Tesla catching fire.




Boeing designer says....
By fteoath64 on 2/4/2013 10:43:37 AM , Rating: 2
""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.""

So that was exactly what happened if you look at the resulting photos of the mess. A whole box almost charred to the metal. Large cell heat leak into a domino effect.Any why did they not put sensors and electronic relays between a few collection of cells ?. Very poor design. And they could not find the issue still. How many sensors so they have in a box, I bet only 2 instead if 50!.




!!
By HelenaSmithe22 on 1/30/13, Rating: -1
"People Don't Respect Confidentiality in This Industry" -- Sony Computer Entertainment of America President and CEO Jack Tretton














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