HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  RESOURCE CENTER  |  INDUSTRIES
REGISTER   |   LOGIN   |   HELP
Page 1/4  >  >>
Cabe Atwell
User Rank
Blogger
Re: Tried, Tested and True...
Cabe Atwell   3/18/2013 4:45:35 PM
NO RATINGS
They have a solution, the FAA ok'd testing. They will be back in action soon.

More on this soon?

C

a.saji
User Rank
Gold
Re: Tried, Tested and True...
a.saji   3/16/2013 1:06:04 AM
NO RATINGS
 "wouldn't hesitate to fly on an airplane that had this battery in it."

@Robortnorcross: Even I wouldn't hesitate to do the same but don't you think it's a bit risky? Also does these things (this one specially) got updates? 

robatnorcross
User Rank
Platinum
Re: Tried, Tested and True...
robatnorcross   3/14/2013 7:08:55 PM
NO RATINGS
"Transportation Secretary Ray LaHood has said he wants to personally conduct a thorough review of the 787 battery situation. Satisfying LaHood would be critical, since the US Department of Transportation oversees the FAA.

I wouldn't hesitate to fly on an airplane that had this battery in it. After all after Ray La Hood (a career politician) who knows everything about engineering aircraft systems, batteries, etc.  is finished with his "review" everything will be fixed. Too bad that he didn't fix the Toyota acceleration problem-- Oh wait he DID.

May be we can get the Navy Admiral who thinks global warming is his biggest problem he has to work with La Hood.

We're F***ed.

Fast
User Rank
Iron
Re: Liquid cooling for Li-ion???
Fast   3/13/2013 8:43:16 AM
NO RATINGS
Clearly the cause of over heating needs to be discovered and solved.  I' m sure that there are solutions that exsist.  I did run across a project where a system was submerged in 3M™ Fluorinert™ Electronic Liquid. What are your thoughts on it or similar products heat transfer and fire suppression abilities?

Orenda
User Rank
Iron
Boeing Batteey
Orenda   3/13/2013 8:06:58 AM
NO RATINGS
I'm sure that I read somewhere earlier that the 787 requires two of these new style batteries at approximately 65 pounds each. I think the same article indicated that equivalent batteries of an already proven design type would weigh 20 to 25 pounds more. Since I work in aerospace, I understand the importance and desire to cut weight, but it woud seem that for approximately 50 pounds in weight savings there should be other alternatives. NiCad has been used for years in aircraft without the same risk level as NiMh. Since this is a totally new design aircraft, I would have to think that it includes all the latest levels of EMI sheilding and protection. Since the FAA is re-evaluating the use of on-board electronic devices, maybe Boeing could work with the FAA a bit to get the use of electronic devices approved in the 787 and then they could do away with things like the hundreds of copies of newspapers that get carried on board evey flight. That alone would probably make up for any weight penalty imposed by using proven battery technology, would probably help to improve consumer confidence in the safety of the aircraft and should helpt to get the program back in the air again.

g_ost
User Rank
Gold
Re: 787 batteries need liquid cooling
g_ost   3/13/2013 6:04:46 AM
NO RATINGS

The theoretical upper stability limit of water, above which oxygen should evolve, is 1.23 V  and is also pH-dependent. Li-Ion battery works at higher voltage.

The triggering mechanism that induces thermal runaway is directly related to the extent of the cathode thermal instability, and increased oxygen generation  Heat generation from the cathode is 3 - 4 times greater than from the graphite anodes at fully charged states because of oxygen that evolves from the cathode lattice above 200 deg C.

I don't think that aqueous cooling will be used to cool direct the electrodes, but there are non-aqueous liquides able to replace the water.

Possibility to implement water in electrode cooling <1%... the risk is to high for this type of Li-Ion battery

Jeffrey
User Rank
Iron
Re: Liquid cooling for Li-ion???
Jeffrey   3/12/2013 4:06:43 PM
NO RATINGS
But isn't that the key point, Charles?  Any peak temperature the battery hit during the combustion is not relevant; once thermal runaway starts, the cell heats itself.  The key point is, was the cell running at a temperature high enough to start the thermal runaway, before it got started, and due to some external load or charge condition, such that a cooling system could have kept the cell temperature below the ignition point.  If so, some cooling system enhancement is needed.  If not, it would not be.

My understanding, which may be wrong, is that once thermal runaway starts, no external cooling will help, the cell just flames itself.

I suspect that the respondents here who are dumping on Boeing are barking up the wrong tree.  I think enough testing was done to assure that operation and charging never drove the cells anywhere near the temperature thermal runaway point.  This would make speculation about extra cooling systems pointless.  And this is what has made the problem so difficult.

I suspect that the problem is in fact in the cells - not necessarily that GS Yuasa "screwed up", that is, permitted a flaw that was known to be wrong, but that some unknown, and therefore uncontrolled and uncontrollable, aspect of production or materials changed.

a.saji
User Rank
Gold
Re: 787 batteries need liquid cooling
a.saji   3/12/2013 12:17:20 PM
NO RATINGS
@g_ost: Yes but dont you think there is a high or like more than 50% possibility of water being connected with the battery electrodes ? 

Dan K
User Rank
Iron
20 months of testing
Dan K   3/12/2013 9:25:25 AM
NO RATINGS
More interesting than the solution is how can an aircraft go thru nearly 2 years or rigors testing, knowing that the batteries are new technology with specific pitfalls, go into service for less than a year and have several of these dramatic failures.  Who is minding the store?

IMHO these batteries failures are inexcusable engineering failures.   Could these failures have happened in the air as easily as they did on the ground?  Do some people need to be fired?

GTOlover
User Rank
Platinum
Re: Tried, Tested and True...
GTOlover   3/12/2013 8:27:36 AM
NO RATINGS
Republican In Name Only! And he works for the current administration, so...

If the FAA does approve a corrective action plan (understanding that this is an unknown time variable), how long do you think it would be for the 787's that are grounded to be flying again? I assume that the existing fleet would get priority fixes, but would they be fixed where they sit, or would they have to get waivers to fly back to Boeing?

In my mind, even after an approved corrective action, this could be a while before these are seen in commercial use again!

Page 1/4  >  >>


Partner Zone
Latest Analysis
For 3D printing to make the jump from rapid prototyping to manufacturing, engineers will need to find easier ways to move products from their CAD screens to their printers.
Gigabit and PoE are two networking technologies moving ahead in tandem as industrial users power remote Ethernet devices such as IP security cameras at 1,000 Mbps over existing CAT5 cable.
When an artificial product is manufactured to match its real-world version, some qualities should be reviewed and discarded.
Joining porous metal to mating components for medical and life sciences applications can be accomplished in a variety of ways.
New versions of BASF's Ecovio line are both compostable and designed for either injection molding or thermoforming. These combinations are becoming more common for the single-use bioplastics used in food service and food packaging applications, but are still not widely available.
More:Blogs|News
Design News Webinar Series
5/30/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
5/29/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
6/25/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
6/27/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
Blogs from Our Sponsors
From Dell / Intel®
New Paradigms in Design Work
Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013    5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
From Dell / Intel®
Increased Workstation Performance Is as Easy as 'DPPO'
Trey Morton, Dell, 4/25/2013    2
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
From Dell / Intel®
Taking Some of the Grit out of Manufacturing
Kirsten Billhardt, Manufacturing Industry Marketing Strategist, Dell, 3/26/2013    5
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Jun 24 - 28, Design Your Own Android App
SEMESTERS: 1  |  2  |  3


DN Radio
Sponsored by
NEXT UPCOMING BROADCAST
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Copyright © 2013 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service