02-08-2013, 06:08 AM
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#121
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Member
Join Date: Jun 2009
Location: FAPE/PLZ
Posts: 136
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Quote:
Originally Posted by Gabriel
I haven't heard of many cases of battery fires in hybrid and electric cars. In fact, I haven't heard of a single one.
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Crash testing the Chevy Volt resulted in two fires - weeks after the test. IIRC the cause was coolant fluid leaking into the damaged battery and causing a short. Nevertheless, during the investigation, even with "severe" physical damage to the battery pack, they did not manage to cause another fire. Post crash protocol was revised to require discharging the battery as a precaution. http://www.wired.com/autopia/2011/11...hevrolet-volt/
And...
Quote:
Originally Posted by Alessandro
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Even SpaceX is successfully using Lithium battery tech.
Methinks Boeing needs to (1) choose a new battery supplier (SpaceX, cut the politics) and (2) stop fooling themselves that lithium batteries don't have the potential to cause fires (hopefully they've learned this by now)
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02-08-2013, 06:37 AM
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#122
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Member
Join Date: Jun 2009
Posts: 187
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Yeah, the Chevy Volt did catch fire.
Apparently, not all Li-ion batteries are the same. They can have different chemistry and some say this makes a fundamental difference. There was also the 'differences in design' opinion from SpaceX.
So can we put all these lithium batteries under the same denominator? Maybe somehow Boeing just chose the most unstable chemistry and design. And what about the safety mechanisms and sophisticated battery electronic control which should have prevented all this? I think the NTSB is looking into that too.
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02-08-2013, 12:44 PM
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#123
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Senior Member
Join Date: Mar 2009
Location: MIA
Posts: 1,125
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well, from what i've read, LiPo batteries have none of the problems that LiIon batteries do. makes ya wonder...
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02-20-2013, 04:27 PM
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#124
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Member
Join Date: Jul 2009
Location: Denver, Colorado
Posts: 148
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So this is Boeing's half-baked solution: http://www.tampabay.com/news/busines...es-say/1275693
Great! Who doesn't want to fly on an airplane where there's a contained fire on board!  The FAA will probably reject this, as they should.
IMO, Boeing needs to quit playing around with their future and just install lead-cadmium batteries in all 787s. This is nuts.
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02-21-2013, 03:52 AM
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#125
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Senior Member
Join Date: Sep 2008
Posts: 1,049
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Quote:
Originally Posted by UALdave
So this is Boeing's half-baked solution: http://www.tampabay.com/news/busines...es-say/1275693
Great! Who doesn't want to fly on an airplane where there's a contained fire on board!  The FAA will probably reject this, as they should.
IMO, Boeing needs to quit playing around with their future and just install lead-cadmium batteries in all 787s. This is nuts.
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Why lead? Why not NiCd?
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02-21-2013, 04:11 AM
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#126
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Senior Member
Join Date: Jan 2008
Location: Buenos Aires - Argentina
Posts: 2,915
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Quote:
Originally Posted by SYDCBRWOD
Why lead? Why not NiCd?
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Why Ni-Cd?
Why not Li-MH, or Li-Po?
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02-21-2013, 11:13 PM
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#127
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Member
Join Date: Jul 2009
Location: Denver, Colorado
Posts: 148
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Quote:
Originally Posted by Gabriel
Why Ni-Cd?
Why not Li-MH, or Li-Po?
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What are Li-MH or Li-Po batteries; what do those letters stand for?? I've mentioned lead-cadmium batteries so much, because, other then lithium-ion, they're the only batteries that I've heard of being used on a commercial aircraft.
So we have a family friend who worked for United for decades, and he said the problem with replacing the lithium-ion batteries with something heavier, is that the airline will be able to carry less passengers. But, better that then a serious safety hazard on-board, IMO.
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02-22-2013, 02:11 AM
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#128
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Senior Member
Join Date: Sep 2008
Posts: 1,049
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Quote:
Originally Posted by UALdave
What are Li-MH or Li-Po batteries; what do those letters stand for?? I've mentioned lead-cadmium batteries so much, because, other then lithium-ion, they're the only batteries that I've heard of being used on a commercial aircraft.
So we have a family friend who worked for United for decades, and he said the problem with replacing the lithium-ion batteries with something heavier, is that the airline will be able to carry less passengers. But, better that then a serious safety hazard on-board, IMO.
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Lead Calcium is probably what started your car this morning. Lead has issues including power density weight to power ratios and the Puekert Effect. Not well suited to an environment requiring lots of power in a short space of time whilst also being light and small.
NiCd (Nickel Cadmiums) are a proven option lighter and smaller than Lead chemistries (but with memory issues and high discharge issues). Nickel Metal Hydride (NiMh) is probably a better bet again.
LiPo (Lithium Polymer) may be straying to close to the unstable end of the spectrum.
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02-22-2013, 06:11 PM
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#129
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Member
Join Date: Jan 2008
Posts: 909
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On a side note one of the areas that US exporters (including Boeing) have to take into consideration is the toxicity of their products. Certain countries and the EU have restrictions on the use of toxic metals such as lead, mercury, cadmium, and chromium. These restriction result in cost when disposing of products such as batteries.
Li-ion batteries can be readily disposed of.
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02-23-2013, 12:02 AM
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#130
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Senior Member
Join Date: Jul 2009
Posts: 1,065
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Just curious. Is the global lithium supply any sort of limiting factor in what batteries can be built into all sorts of electronics and transportation? Any research on viable non-lithium options? Seems like you see lithium in everything these days. (Apropos of nothing, I wish I'd put 25 percent of my retirement money in platinum a few years back)
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02-25-2013, 11:32 AM
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#131
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Member
Join Date: Jul 2004
Posts: 435
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Quote:
Originally Posted by UALdave
So this is Boeing's half-baked solution: http://www.tampabay.com/news/busines...es-say/1275693
Great! Who doesn't want to fly on an airplane where there's a contained fire on board!  The FAA will probably reject this, as they should.
IMO, Boeing needs to quit playing around with their future and just install lead-cadmium batteries in all 787s. This is nuts.
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I'm sure they have a plan B which involves lead-cadmium or something other than Li-Ion. But if they can hoodwink the FAA into letting them fly with increased containment system they will. They have obviously identified this as the optimum solution and will campaign for it for all they are worth.
If it doesn't work they will have a Plan B with safer Battery Choice.
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02-25-2013, 10:10 PM
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#132
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Member
Join Date: Jan 2008
Posts: 909
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Quote:
Originally Posted by EconomyClass
Just curious. Is the global lithium supply any sort of limiting factor ..............
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I don't think so. I use Al-Li alloys for aerospace structures and have never heard that there mat be a lithium shortage. However the main cost impact of using Al-Li (over other al alloys) is that special friction stir weld equipment is required.
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02-25-2013, 10:23 PM
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#133
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Member
Join Date: Jan 2008
Posts: 909
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Quote:
Originally Posted by tsv
I'm sure they have a plan B which involves lead-cadmium ..............
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Twp posters have mentioned lead-cadmium batteries; as far as I know there is no such nbattery type. There are lead-acid and nickel-cadmium batteries.
For info on battery power capabilities see attached plot from Aviation Week.
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02-27-2013, 01:51 PM
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#134
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Member
Join Date: Jul 2004
Posts: 435
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Quote:
Originally Posted by Highkeas
Twp posters have mentioned lead-cadmium batteries; as far as I know there is no such nbattery type. There are lead-acid and nickel-cadmium batteries.
For info on battery power capabilities see attached plot from Aviation Week.
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Sorry for my mistake, you are correct of course. But anyway they will have several plans. If possible they will persevere with the LI-ION option with enhanced containment because there will be less new systems to be tested and approved so less down time. And if they manage to get approval for the Lithium option (again) there will probably be weight benefits.
But if the FAA get shaky about Li-Ion and want Nickel-Cadmium/Lead Acid or whatever they will have a Plan B ready to accommodate theme. Obviously at the end of the day they need the 787 back in the Air no matter what because they can still make a lot of money out of this Aircraft in the longer term. Or lose a lot if it doesn't get it's wings back.
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02-28-2013, 01:23 PM
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#135
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Senior Member
Join Date: Jan 2003
Location: European Union
Posts: 1,027
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Quote:
Originally Posted by EconomyClass
Just curious. Is the global lithium supply any sort of limiting factor in what batteries can be built into all sorts of electronics and transportation? Any research on viable non-lithium options? Seems like you see lithium in everything these days. (Apropos of nothing, I wish I'd put 25 percent of my retirement money in platinum a few years back)
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OT no, large untapped resources in Chile and Bolivia.
Back to the 787 grounding,
both JAL and ANA has now cancelled 787 flights until end of May.
__________________
"The real CEO of the 787 project is named Potemkin"
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02-28-2013, 05:45 PM
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#136
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Member
Join Date: Jul 2009
Location: Denver, Colorado
Posts: 148
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So, what type of battery does the 747-8 use? Because they haven't the problems that the 787 has.
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02-28-2013, 06:10 PM
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#137
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Member
Join Date: Jan 2008
Posts: 909
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Quote:
Originally Posted by UALdave
So, what type of battery does the 747-8 use? Because they haven't the problems that the 787 has.
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Earlier commercial airplane models, such as the 777, 747 and MD-11, used nickel cadmium (NiCd) batteries, which are heavier, larger and less powerful.
Source: http://787updates.newairplane.com/78...nced-Airplanes
I think this should say: "...........heavier and larger for equal power."
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02-28-2013, 06:30 PM
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#138
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Member
Join Date: Jul 2009
Location: Denver, Colorado
Posts: 148
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Quote:
Originally Posted by Highkeas
Earlier commercial airplane models, such as the 777, 747 and MD-11, used nickel cadmium (NiCd) batteries, which are heavier, larger and less powerful.
Source: http://787updates.newairplane.com/78...nced-Airplanes
I think this should say: "...........heavier and larger for equal power."
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OK, thanks! Well, Boeing is allowed now to carry out some test flights with what they think is their battery fix/solution. It will be interesting to see how those go.
When do people on here think that the 787 will resume commercial service? I've read people who say that it will resume this summer, but I don't know.
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03-01-2013, 08:25 PM
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#139
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Senior Member
Join Date: Jan 2008
Location: Buenos Aires - Argentina
Posts: 2,915
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Quote:
Originally Posted by Highkeas
Earlier commercial airplane models, such as the 777, 747 and MD-11, used nickel cadmium (NiCd) batteries, which are heavier, larger and less powerful.
Source: http://787updates.newairplane.com/78...nced-Airplanes
I think this should say: "...........heavier and larger for equal power."
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I'm sure you'll find some range beyond the size of a Li-ion battery but before reaching an equal power where the NiCd will be all three heavier, lager and less powerful.
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