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Is lithium ion battery technology still not there?

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cameo

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Feb 21, 2013, 10:49:44 PM2/21/13
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Boeing has a hell of a time with fixing its battery problem on the 787
Dreamliner. I wonder if any of you had a deeper knowledge as to the
cause and whether those batteries are just not yet a proven technology.

Sylvia Else

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Feb 21, 2013, 10:56:06 PM2/21/13
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I think it's more just that they're an inherently unstable technology.
Design them right, and they'll be OK, but it's easy to make mistakes,
overlook things, etc., such that their inherent instability will lead to
trouble.

I wouldn't be building them into aircraft.

Sylvia.

hamilton

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Feb 21, 2013, 10:57:46 PM2/21/13
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Tom Hoehler

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Feb 21, 2013, 11:16:55 PM2/21/13
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"hamilton" <hami...@nothere.com> wrote in message
news:kg6qa0$n46$1...@dont-email.me...
Airbus says they will not be using Li-ion batteries. Pussies.

bloggs.fred...@gmail.com

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Feb 22, 2013, 12:30:14 AM2/22/13
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On Thursday, February 21, 2013 10:57:46 PM UTC-5, hamilton wrote:

> http://www.usatoday.com/story/travel/flights/2013/02/20/japan-probe-finds-miswiring-of-boeing-787-battery/1932109/

"The [Japan] Transport Safety Board said in a report that the battery for the aircraft's auxiliary power unit was incorrectly connected to the main battery that overheated, although a protective valve would have prevented power from the auxiliary unit from causing damage."

Boeing and NTSB found no such miswiring on the JAL 787 where APU battery caught fire. ANA fire Japan is investigating was the EE-bay main battery, not the APU battery.

T

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Feb 22, 2013, 2:44:14 AM2/22/13
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In article <kg6pq5$ls5$1...@dont-email.me>, ca...@unreal.invalid says...
>
> Boeing has a hell of a time with fixing its battery problem on the 787
> Dreamliner. I wonder if any of you had a deeper knowledge as to the
> cause and whether those batteries are just not yet a proven technology.

It's turned out not to be the battery but instead a wiring fault.
Imagine that.


Sylvia Else

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Feb 22, 2013, 4:07:05 AM2/22/13
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There was a wiring fault. That doesn't mean it caused the battery to
catch fire. Indeed, were a wiring fault capable of doing that, one would
have to feel that the design had no business being in the air.

Sylvia.

John Larkin

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Feb 22, 2013, 10:37:56 AM2/22/13
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On Fri, 22 Feb 2013 14:56:06 +1100, Sylvia Else <syl...@not.at.this.address>
wrote:

>On 22/02/2013 2:49 PM, cameo wrote:
>> Boeing has a hell of a time with fixing its battery problem on the 787
>> Dreamliner. I wonder if any of you had a deeper knowledge as to the
>> cause and whether those batteries are just not yet a proven technology.
>
>I think it's more just that they're an inherently unstable technology.

High energy density is inherently dangerous.


--

John Larkin Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

bloggs.fred...@gmail.com

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Feb 22, 2013, 11:44:03 AM2/22/13
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On Friday, February 22, 2013 4:07:05 AM UTC-5, Sylvia Else wrote:

>
> There was a wiring fault. That doesn't mean it caused the battery to
>
> catch fire. Indeed, were a wiring fault capable of doing that, one would
>
> have to feel that the design had no business being in the air.

"T" stands for troll.
No such wiring fault has been found or confirmed. JTSB is under extreme pressure to find an answer, the best they have come up so far is an "appearance" of miswiring through a protective "valve"- yeah, rght.

Jeff Liebermann

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Feb 22, 2013, 12:08:59 PM2/22/13
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On Thu, 21 Feb 2013 19:49:44 -0800, cameo <ca...@unreal.invalid>
wrote:

>Boeing has a hell of a time with fixing its battery problem on the 787
>Dreamliner. I wonder if any of you had a deeper knowledge as to the
>cause and whether those batteries are just not yet a proven technology.

I wonder if ANY battery technology will ever be really safe. For
example, lead acid batteries are well known and allegedly safe, yet we
still have exploding car batteries:
<https://www.google.com/#q=exploding+car+battery>
<https://www.google.com/search?q=exploding+car+battery&tbm=isch>
Concentrate enough energy in a small enough volume and you have the
potential for simulating a bomb. Hydrogen fuel cells have a similar
explosive potential. If radioactive battery technology suddenly
becomes fashionable, we will have similar problems.

So, what will it take to make it a "proven" technology? Well, the FAA
certainly has restrictions that follow its definition of safe. Such
restrictions were applied to LiIon batteries for shipping and travel:
<http://safetravel.dot.gov/definitions.html>
where any more than 25 grams ELC (equivalent lithium content) or about
a 300 watt hour battery is forbidden. Unattached (spare) batteries
are not acceptable.

While it is legal to install an very large LiIon battery aboard a
Dreamliner, it is apparently not legal to ship the same battery in a
box as a replacement.
<http://www.aviationpros.com/news/10877946/icao-moves-to-kill-air-cargo-exemption-for-lithium-ion-batteries>
Therefore, LiIon must be safe to install, but not to transport. The
mind boggles.

The problem is that its very easy to demonstrate that something is
unsafe, but impossible to prove that something is safe. This is the
dilemma facing the FAA with all new technology. The tendency is to
ban anything new until other industries shake out the bugs and
generate some kind of track record. Approving the LiIon battery would
have been considered safe by this logic because of all the laptop and
cell phone batteries in use, and all the research into electric
vehicle batteries. So, the FAA is stuck with a decision. Do they
delay claiming "more research is necessary", or do they approve the
Boeing band aids intended to somehow make an inherently dangerous
device safe. Dunno.



--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann

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Feb 22, 2013, 12:24:58 PM2/22/13
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On Fri, 22 Feb 2013 02:44:14 -0500, T <kd1s....@cox.nospam.net>
wrote:
Baloney. Almost all LiIon cells have EXTERNAL short circuit
protection. I you tear apart a common 18650 cell, under the negative
terminal is the necessary protective electronics.
<https://www.google.com/search?q=18650+protection+circuit&tbm=isch>
Same with laptop LiIon batteries. Presumably, the Boeing battery also
has short circuit protection. Only politicians and the press would
believe that story.

Pretend that you're an FAA administrator, under political pressure to
get the Dreamliner back into the air. You have to do something and
fast. If you blame the battery, the fleet remains grounded until a
rather long and extensive series of qualification tests are performed.
However, if you conjur a magic alternative cause, you can declare the
battery to be safe, and allow the Dreamliners back in the air.
Meanwhile, you can say your prayers and hope that the Boeing band aids
will prevent any further fires while Boeing furiously redesigns the
battery. That fits in nicely with today pronouncement:
<http://www.foxnews.com/politics/2013/02/22/boeing-proposing-long-term-fix-for-787-batteries/>

Incidentally, my guess(tm) is that the rigid case of the Boeing
battery is the culprit. LiIon batteries like to expand. If
constrained, the electrode connections like to punch through the
various insulating layers creating an internal short circuit. Again,
this is just my guess(tm) with no warranty expressed or implied.

Tim Wescott

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Feb 22, 2013, 12:51:52 PM2/22/13
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It's certainly "there" for a lot of applications. I think that I would
rather have a cell phone the size that it is now and undergo a 1:1000000
risk having my pants catch on fire than have one of the old ones that's
as big as a shoe.

Larkin mentioned that high energy densities make for high risk -- he's
right, but they make for high convenience and that can outweigh a lot of
risk.

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

TTman

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Feb 22, 2013, 2:27:46 PM2/22/13
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>
> Incidentally, my guess(tm) is that the rigid case of the Boeing
> battery is the culprit. LiIon batteries like to expand. If
> constrained, the electrode connections like to punch through the
> various insulating layers creating an internal short circuit. Again,
> this is just my guess(tm) with no warranty expressed or implied.
>
>
> --
> Jeff Liebermann je...@cruzio.com
> 150 Felker St #D http://www.LearnByDestroying.com
> Santa Cruz CA 95060 http://802.11junk.com
> Skype: JeffLiebermann AE6KS 831-336-2558

I subscribe to that too.... Having seen far too many 'incidents' with RC
LiPos catching fire/bulging etc.


Yzordderrex

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Feb 22, 2013, 3:07:52 PM2/22/13
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The Lithium-Ion battery is a logical choice for the application. I would be cautious as to diagnosing the problem just yet. Certain lithium battery chemistries are more prone than others to fail with a fire. The battery in the Dreamliner (if my intel is good) is of a chemistry that would be better suited to remain on the surface of the earth. Failures could be a result of a few different scenarios, including a faulty cell to begin with, overcharging, and certainly mis-wiring the battery or a faulty BMU or charger board.

I'm sure we will have an answer soon, although an answer grounded in reality may never arrive. Just the way these things work out.

NEO

bloggs.fred...@gmail.com

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Feb 22, 2013, 3:42:56 PM2/22/13
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On Friday, February 22, 2013 12:24:58 PM UTC-5, Jeff Liebermann wrote:

>
> Baloney.

"T" is for troll, eternal-september troll.

> Almost all LiIon cells have EXTERNAL short circuit
>
> protection. I you tear apart a common 18650 cell, under the negative
>
> terminal is the necessary protective electronics.

Those are required by international regulation, they're not a nice-to-have the manufacturer decided to add.


> Pretend that you're an FAA administrator, under political pressure to
>
> get the Dreamliner back into the air.

That guy can't utter three buzzwords without looking down at his cue card. All he's doing is trying to figure out how he can issue a decision based on some other authority he can eventually scapegoat if it turns out to be wrong.

>
>
> Incidentally, my guess(tm) is that the rigid case of the Boeing
>
> battery is the culprit. LiIon batteries like to expand. If
>
> constrained, the electrode connections like to punch through the
>
> various insulating layers creating an internal short circuit. Again,
>
> this is just my guess(tm) with no warranty expressed or implied.

Nah- it runs much deeper than that. You would be seeing a helluva lot more than just two fires in 100,000 hours with that kind of defect. The batteries are cycled through simulated altitude testing, again by international regulation. Do you think anyone in their right mind would use a battery in a high altitude aviation application without designing in that kind of ruggedness?

In other news, JTSB did announce a few days ago that the second battery in the subject ANA 787 was found to be "swollen" too.

bloggs.fred...@gmail.com

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Feb 22, 2013, 3:59:47 PM2/22/13
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On Friday, February 22, 2013 3:07:52 PM UTC-5, Yzordderrex wrote:
> Failures could be a result of a few different scenarios, including a faulty cell >to begin with, overcharging, and certainly mis-wiring the battery or a faulty BMU >or charger board.

But those failures are supposed to result in a dead battery (open ckt) and not fire, venting, or smoking. The safeguards against catastrophic failure, at least four internal to the cells, failed.


> I'm sure we will have an answer soon, although an answer grounded in reality may never arrive. Just the way these things work out.
>

Don't count on it. Boeing is already working on designing it out of the system. United has removed the 787 from their flight plans <hint hint>. Now wait for the "out of an abundance of caution" bs from Boeing public relations.

Jeff Liebermann

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Feb 22, 2013, 6:58:01 PM2/22/13
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On Fri, 22 Feb 2013 12:42:56 -0800 (PST),
bloggs.fred...@gmail.com wrote:


>"T" is for troll, eternal-september troll.

I judge at the content, not the author.

>Those are required by international regulation, they're not a nice-to-have the manufacturer decided to add.

Unprotected 18650
<http://dx.com/p/ultrafire-lc-17670-1800mah-3-6v-rechargeable-battery-2844>
Protected 18650
<http://dx.com/p/ultrafire-2400mah-3-7v-protected-18650-cell-1283>

>That guy can't utter three buzzwords without looking down at his cue card.
>All he's doing is trying to figure out how he can issue a decision based
>on some other authority he can eventually scapegoat if it turns out to
>be wrong.

Agreed. The first step to solving a problem is to blame someone.
Also, you cannot blame anyone that is instrumental in fixing the
problem. So, the Dreamliners sit on the ground until a suitable
culprit can be found.

>Nah- it runs much deeper than that. You would be seeing a helluva
>lot more than just two fires in 100,000 hours with that kind of defect.
>The batteries are cycled through simulated altitude testing, again
>by international regulation.

The problem with testing is that it's really not exactly the same as
the real installation. You can't really test everything on the ground
(as in Hubble telescope). Some of the more exotic problems with
airplanes were only identified after some airplanes fell out of the
sky. I suspect this is more of the same. Something was overlooked in
the battery design and testing.

>Do you think anyone in their right mind would use a battery in a
>high altitude aviation application without designing in that kind
>of ruggedness?

Absolutely yes. Have you ever seen what's flying under the umbrella
of "experimental aviation"? Ok, this isn't experimental aviation.
It's just the first run of a new design, which just experienced a
single problem. Perhaps we're forgetting that all of the other
systems on the Dreamliner worked as expected. Were the problem less
catastrophic, it could easily have been a footnote on an obscure
report instead of headline news.

>In other news, JTSB did announce a few days ago that the second
>battery in the subject ANA 787 was found to be "swollen" too.

Hint: Find an unpackaged Li-Ion cell and measure the change in
diameter at different states of charge at elevated temperatures (as
found inside laptops).
<http://www.electrochem.org/dl/ma/203/pdfs/0110.pdf>
I did a similar measurement at room temperature and also found some
swelling. Cramming in as many cells as physically possible without an
expansion joint is my guess(tm) as to the basic problem.

Yzordderrex

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Feb 22, 2013, 8:03:53 PM2/22/13
to
On Friday, February 22, 2013 3:59:47 PM UTC-5, bloggs.fred...@gmail.com wrote:
> On Friday, February 22, 2013 3:07:52 PM UTC-5, Yzordderrex wrote:
>
> > Failures could be a result of a few different scenarios, including a faulty cell >to begin with, overcharging, and certainly mis-wiring the battery or a faulty BMU >or charger board.
>
>
>
> But those failures are supposed to result in a dead battery (open ckt) and not fire, venting, or smoking. The safeguards against catastrophic failure, at least four internal to the cells, failed.


Not sure where you are getting your info, but open circuit failure of a Li-ion battery probably isn't going to happen. The particular recipe that the 787 is using is notorious for catching fire. Newer designs used to spin up the turbines to light them off use a much more air-worthy chemistry

The batteries are not stuffed into the package like a can of sardines waiting to expand and catch fire. if you take a look at one of these assemblies you will see there is room to drive a small truck between rows of cells.

And yes, I agree, the batteries in the 787 will most likely be replaced by the end of the year with more forgiving units.

regards,
N9NEO

Yzordderrex

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Feb 22, 2013, 8:04:29 PM2/22/13
to
On Friday, February 22, 2013 6:58:01 PM UTC-5, Jeff Liebermann wrote:
> On Fri, 22 Feb 2013 12:42:56 -0800 (PST),
>
> bloggs.fred...@gmail.com wrote:
>
>
>
>
>
> >"T" is for troll, eternal-september troll.
>
>
>
> I judge at the content, not the author.
>
>
>
> >Those are required by international regulation, they're not a nice-to-have the manufacturer decided to add.
>
>
>
> Unprotected 18650
>
>
>
> Protected 18650

Jeff Liebermann

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Feb 22, 2013, 11:15:55 PM2/22/13
to
On Fri, 22 Feb 2013 17:03:53 -0800 (PST), Yzordderrex
<powersu...@netzero.net> wrote:

>The batteries are not stuffed into the package like a can of sardines
>waiting to expand and catch fire. if you take a look at one of these
>assemblies you will see there is room to drive a small truck
>between rows of cells.

Ummm... what room?
<http://static1.businessinsider.com/image/5113ec4969beddab3e000007-930-697-399-299/ntsb-boeing-dreamliner-investigation-battery-presentation-1.png>

<http://www.fareastgizmos.com/transport/ana-dreamliner-battery-blaze-traced-to-runaway-overheating.php>
Note the batteries on the left with the cells packed in rather tightly
in what looks like a hermetically sealed metal box. There's some
space between batteries, but not between the cells crammed into each
battery case:
<http://english.kyodonews.jp/photos/2013/01/205983.html>
<http://www.businessinsider.com/update-on-dreamliner-battery-failure-probe-2013-2>

I Googled and could only find fried battery photos or original
certification photos, both of which failed to show any gaps.
<https://www.google.com/search?tbm=isch&q=dreamliner+battery>
A link to a photo showing these gaps between the cells please?

>And yes, I agree, the batteries in the 787 will most likely be
>replaced by the end of the year with more forgiving units.

Agreed. Maybe an internal fire extinguisher or cooling system to
prevent or restrict runaway lithium ignition. Looking at the top
photo, there are already plenty of sensors.

Robert Baer

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Feb 23, 2013, 12:03:20 AM2/23/13
to
Those batteries are a "proven" technology.
However, use has shown that they are not only temperature sensitive,
but that they are prone to thermal runaway; energy density so high as to
cause fires - just like gasoline which has even higher energy density.
Now there is a newer Li formulation that is NOT as temperature
sensitive, and seems to NOT beprone to thermal runaway.
Was not available back in the dinosaur age when the battery choice
was made.

Robert Baer

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Feb 23, 2013, 12:06:40 AM2/23/13
to
Methinks they put themselves between a rock and a hard place..the
Dreamliner MANDATE was to make _everything_ as light as possible,and
that stubborn attitude ruled out Lead-Acid and Nickel-Silver formulations.


bloggs.fred...@gmail.com

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Feb 23, 2013, 1:29:29 AM2/23/13
to
On Friday, February 22, 2013 8:03:53 PM UTC-5, Yzordderrex wrote:

> > But those failures are supposed to result in a dead battery (open ckt) and not fire, venting, or smoking. The safeguards against catastrophic failure, at least four internal to the cells, failed.
>
>
>
>
>
> Not sure where you are getting your info, but open circuit failure of a Li-ion battery probably isn't going to happen. The particular recipe that the 787 is using is notorious for catching fire. Newer designs used to spin up the turbines to light them off use a much more air-worthy chemistry

Things like shut-down separator, tear-away tab, and thermal circuit interrupters are intended to make the battery an open circuit, some permanently. The first line of defense is the separator, a layer of which melts near thermal runaway, and blocks all ion flow between electrodes. The others are backups. You're right, but not the way you think, "open circuit failure" /is/ "probably not going to happen."


bloggs.fred...@gmail.com

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Feb 23, 2013, 1:39:53 AM2/23/13
to
On Friday, February 22, 2013 6:58:01 PM UTC-5, Jeff Liebermann wrote:

>
> Hint: Find an unpackaged Li-Ion cell and measure the change in
>
> diameter at different states of charge at elevated temperatures (as
>
> found inside laptops).
>
> <http://www.electrochem.org/dl/ma/203/pdfs/0110.pdf>
>
> I did a similar measurement at room temperature and also found some
>
> swelling. Cramming in as many cells as physically possible without an
>
> expansion joint is my guess(tm) as to the basic problem.
>

Okay, but the pressure relief valve is supposed to vent well before the internal pressure gets to the point of puncturing the separator. If they have fire, they have separator failure, it's that simple. The separator is supposed to fuse its pores shut permanently /before/ thermal runaway temperature is reached, and it does this on the dimension scale of microns. You can't have thermal runaway with a working separator. There are a few things that can happen to defeat the separator, like dendrite growth and pore blocking contamination, or it can be overvoltaged when fused, to the point of having enough leakage to sustain thermal runaway, and who knows what else. Supposedly the Yuasa prismatic package which uses a 10 meter length of separator is unprecedented.

Jeff Liebermann

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Feb 23, 2013, 11:38:12 AM2/23/13
to
On Fri, 22 Feb 2013 22:39:53 -0800 (PST),
bloggs.fred...@gmail.com wrote:

>Okay, but the pressure relief valve is supposed to vent well
>before the internal pressure gets to the point of puncturing
>the separator. If they have fire, they have separator failure,
>it's that simple. The separator is supposed to fuse its pores
>shut permanently /before/ thermal runaway temperature is
>reached, and it does this on the dimension scale of microns.
>You can't have thermal runaway with a working separator. There
>are a few things that can happen to defeat the separator, like
>dendrite growth and pore blocking contamination, or it can be
>overvoltaged when fused, to the point of having enough leakage
>to sustain thermal runaway, and who knows what else. Supposedly
>the Yuasa prismatic package which uses a 10 meter length of
>separator is unprecedented.

Sounds good, if the battery actually had such protection. My
suspicious nature suggests that this is an old design that may not
have had such a safety feature.

Would you believe an internal short?
<http://www.flightglobal.com/news/articles/ntsb-finds-signs-of-short-circuit-thermal-runaway-in-jal-787-battery-failure-381464/>
Admittedly, it's guesswork, but if this is to be believed, everything
following starts to smell like a cover up.

Digging for Yuasa LVP65 data. (Lithium cobalt dioxide and carbon):
<http://www.gsyuasa-lp.com/download/file/fid/111>
<http://www.gsyuasa-lp.com/download/file/fid/112>
Nothing on internal construction. Lithium cobalt goes into thermal
runaway earlier than later technologies:
<http://i337.photobucket.com/albums/n385/motidog/787batt02_zps393f8581.jpg>

This might be a clue:
<http://www.flightglobal.com/news/articles/boeing-looks-to-boost-787-lithium-ion-battery-service-life-224663/>
Were the failed batteries the old or new design? I couldn't find
anything.

The plot gets thicker if you include the 2007 Secureplane fire, which
was started when one of the 787 batteries exploded. Of course, the
tech running the test was fired as a suitable scapegoat especially
after he claimed that the battery was unsafe after trying to charge it
with no sensors attached:
<http://www.oalj.dol.gov/Decisions/ALJ/AIR/2008/LEON_MICHAEL_v_SECURAPLANE_TECHNOLO_2008AIR00012_%28JUL_15_2011%29_172333_CADEC_SD.PDF>

It's not like Boeing didn't know about the problem:
<http://www.aero-news.net/subsite.cfm?do=main.textpost&id=66f459f8-4d6b-452b-961a-6b80dc4830a1>

Take a look at this photo of a failed 787 battery:
<http://www.fareastgizmos.com/transport/ana-dreamliner-battery-blaze-traced-to-runaway-overheating.php>
Would you say that the bulging metal battery cases indicates that some
expansion had taken place? Unless the investigators pried open the
battery cases by expanding the sides, which is unlikely as the
individual cells would have been ruined and unsuitable for a post
mortem dissection, 6 of the 8 batteries appear to have significant
bulging. Offhand, the individual LVP65 batteries look exactly like
the traditional NiCd aircraft batteries.

What I find odd is that 6 of the 8 cells overheated. I would
guess(tm) that simultaneous internal failure in 6 cells is rather
unlikely. Also the metal cases seem to have enough space between them
(possibly for cooling) to prevent simultaneous ignition. Whatever
caused the fire had to affect 6 of the 8 batteries almost
simultaneously as a delayed failure would show a more staggered damage
pattern.

Actually there is a hint of a staggered ignition pattern. Note in the
above photo that the degree of bulging varies across the assembly. The
sides are more bowed outwards towards the right side (near the
connectors), than on the other side. The right two batteries also
have swelled sufficiently to create a concave indentation in the
adjacent two batteries, that's not apparent in the other cells. That
would suggest that ignition started with the two cells at the right
and propagated to the left. What I find odd is the apparent symmetry
of the two rows of batteries, which suggests simultaneous ignition of
the two right cells.

Place your bets. I'll wager that the FAA bans Li-Ion batteries and
goes back to good olde NiCd batteries.

Jeff Liebermann

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Feb 23, 2013, 12:11:43 PM2/23/13
to
On Sat, 23 Feb 2013 08:38:12 -0800, Jeff Liebermann <je...@cruzio.com>
wrote:


More on LiIon battery technology and failures:
<http://www.mpoweruk.com/lithium_failures.htm>
which includes a better graph of the temperature at which the various
battery chemistries go into thermal runaway.

It adds an interesting note:
"Note that consumer concern about the safety of Lithium batteries
tends to be focused on the Lithium cathode materials, whereas in
reality, thermal runaway is initiated at the anode, NOT the
cathode."
Carbon anode. Silicon would be safer and deliver more power, but such
cells expand and contract 4:1 which would be rather difficult to
package. Accordion package? Sponge anode?
<http://news.rice.edu/2012/11/01/rice-team-boosts-silicon-based-batteries-2/>

bloggs.fred...@gmail.com

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Feb 23, 2013, 2:01:25 PM2/23/13
to
On Saturday, February 23, 2013 12:11:43 PM UTC-5, Jeff Liebermann wrote:
> On Sat, 23 Feb 2013 08:38:12 -0800, Jeff Liebermann <je...@cruzio.com>
>
> wrote:
>
>
>
>
>
> More on LiIon battery technology and failures:
>
> <http://www.mpoweruk.com/lithium_failures.htm>
>
> which includes a better graph of the temperature at which the various
>
> battery chemistries go into thermal runaway.

Right, but the separator protection kicks in at 130oC which is well before the temps shown on the curve. The separator is an inner ply of 10u thick polypropylene porous film sandwiched between two 10u porous polyethylene film sheets.

>
>
>
> It adds an interesting note:
>
> "Note that consumer concern about the safety of Lithium batteries
>
> tends to be focused on the Lithium cathode materials, whereas in
>
> reality, thermal runaway is initiated at the anode, NOT the
>
> cathode."
>
> Carbon anode. Silicon would be safer and deliver more power, but such
>
> cells expand and contract 4:1 which would be rather difficult to
>
> package. Accordion package? Sponge anode?
>
> <http://news.rice.edu/2012/11/01/rice-team-boosts-silicon-based-batteries-2/>
>

Apparently there are quite a few variations on lithium ion, but of them all LiCoO2 offers the highest energy density.

bloggs.fred...@gmail.com

unread,
Feb 23, 2013, 2:09:12 PM2/23/13
to
On Saturday, February 23, 2013 11:38:12 AM UTC-5, Jeff Liebermann wrote:

>
> Sounds good, if the battery actually had such protection. My
>
> suspicious nature suggests that this is an old design that may not
>
> have had such a safety feature.

Huh? There's no such thing as a Lithium battery without a separator. One of the news reports showed it unwrapped on a long bench at the NTSB materials lab.

>
>
>
> Would you believe an internal short?
>
> <http://www.flightglobal.com/news/articles/ntsb-finds-signs-of-short-circuit-thermal-runaway-in-jal-787-battery-failure-381464/>
>
> Admittedly, it's guesswork, but if this is to be believed, everything
>
> following starts to smell like a cover up.

The internal short is what you get when the separator fails.

>
>
>
> Digging for Yuasa LVP65 data. (Lithium cobalt dioxide and carbon):
>
> <http://www.gsyuasa-lp.com/download/file/fid/111>
>
> <http://www.gsyuasa-lp.com/download/file/fid/112>
>
> Nothing on internal construction. Lithium cobalt goes into thermal
>
> runaway earlier than later technologies:
>
> <http://i337.photobucket.com/albums/n385/motidog/787batt02_zps393f8581.jpg>
>
>
>
> This might be a clue:
>
> <http://www.flightglobal.com/news/articles/boeing-looks-to-boost-787-lithium-ion-battery-service-life-224663/>
>
> Were the failed batteries the old or new design? I couldn't find
>
> anything.

I think that upgrade went by the wayside, all the battery consultants who know about the Boeing design say they're LiCoO2.
That's exactly what they're doing.

This individual is the one who doubts Yuasa, or any manufacturer, can bring enough quality control to bear to make a /safe/ prismatic cell on this scale:
http://www.northeastern.edu/leap/energystorage.html

josephkk

unread,
Feb 23, 2013, 11:21:45 PM2/23/13
to
On Fri, 22 Feb 2013 07:37:56 -0800, John Larkin
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:

>On Fri, 22 Feb 2013 14:56:06 +1100, Sylvia Else <syl...@not.at.this.address>
>wrote:
>
>>On 22/02/2013 2:49 PM, cameo wrote:
>>> Boeing has a hell of a time with fixing its battery problem on the 787
>>> Dreamliner. I wonder if any of you had a deeper knowledge as to the
>>> cause and whether those batteries are just not yet a proven technology.
>>
>>I think it's more just that they're an inherently unstable technology.
>
>High energy density is inherently dangerous.

I do not exactly agree with inherently dangerous. I say inherently
difficult (to damn difficult) to do safely. See sodium-sulphur batteries.
?-)

Richard Henry

unread,
Feb 24, 2013, 4:35:59 AM2/24/13
to
On Feb 23, 8:21 pm, josephkk <joseph_barr...@sbcglobal.net> wrote:
> On Fri, 22 Feb 2013 07:37:56 -0800, John Larkin
>
Arre yo proposing that sodium-sulfur batteries are not inherently
dangerous?

Sylvia Else

unread,
Feb 24, 2013, 7:42:21 AM2/24/13
to
That's not how I read it.

Sylvia.

legg

unread,
Feb 24, 2013, 10:49:59 AM2/24/13
to
On Fri, 22 Feb 2013 15:58:01 -0800, Jeff Liebermann <je...@cruzio.com>
wrote:

>On Fri, 22 Feb 2013 12:42:56 -0800 (PST),
>bloggs.fred...@gmail.com wrote:
>
>
>>"T" is for troll, eternal-september troll.
>
>I judge at the content, not the author.
>
>>Those are required by international regulation, they're not a nice-to-have the manufacturer decided to add.
>
>Unprotected 18650
><http://dx.com/p/ultrafire-lc-17670-1800mah-3-6v-rechargeable-battery-2844>
>Protected 18650
><http://dx.com/p/ultrafire-2400mah-3-7v-protected-18650-cell-1283>
>

Protection mechanisms don't need no steenkeen printed circuit board.

A simply polymer layer, placed in the end seal, can swell to
disconnect the exposed end terminal from the battery proper, if
overheated. This is a common physical feature of many types of
rechargeable 'dumb' batteries.

Not really popular, because imprecise and tending to disconnect with
age/accumulated hours/ambient exposure.

Neither (pcb or polymer) protects against internal-fault-generated
heat.

RL

John Larkin

unread,
Feb 24, 2013, 1:30:06 PM2/24/13
to
On Sat, 23 Feb 2013 20:21:45 -0800, josephkk <joseph_...@sbcglobal.net>
wrote:

>On Fri, 22 Feb 2013 07:37:56 -0800, John Larkin
><jjla...@highNOTlandTHIStechnologyPART.com> wrote:
>
>>On Fri, 22 Feb 2013 14:56:06 +1100, Sylvia Else <syl...@not.at.this.address>
>>wrote:
>>
>>>On 22/02/2013 2:49 PM, cameo wrote:
>>>> Boeing has a hell of a time with fixing its battery problem on the 787
>>>> Dreamliner. I wonder if any of you had a deeper knowledge as to the
>>>> cause and whether those batteries are just not yet a proven technology.
>>>
>>>I think it's more just that they're an inherently unstable technology.
>>
>>High energy density is inherently dangerous.
>
>I do not exactly agree with inherently dangerous. I say inherently
>difficult (to damn difficult) to do safely. See sodium-sulphur batteries.
>?-)

What's the difference, besides playing lawyer with words? If you have masses of
two substances that react energetically and exothermically, densely packaged in
the same volume, with a deliberately thin separator, expect trouble.

The ideal battery would keep the reactive components separated. A fuel cell, or
its liquid equivalent, would keep the reactants in separate tanks and only pipe
in what's needed into the reaction space. Something like zinc-air admits one
reactant from outside.

Primary batteries tend to be safer than rechargables. I wonder if airplanes
could use primary batteries.

Seems like bad economics to ground a fleet of roughly $200 million planes to
save about 1000 pounds per.

SoothSayer

unread,
Feb 24, 2013, 1:42:52 PM2/24/13
to
On Sun, 24 Feb 2013 10:30:06 -0800, John Larkin
About 25 years ago or so, the US Navy came up with Hydrogen fuel cells.
Not like what we have now, IIRC. They were essentially a gas cylinder
with Hydrogen gas in it under pressure, and when fully charged it was
like 90 psi, and it dropped in pressure as it discharged. Do not know
what the energy density or construction was, and they would likely be
pretty heavy unless they used Aluminum cylinders/chambers.

They were certainly a rechargeable design. Don't know if such a thing
would be a suitable replacement. Hydrogen is flammable. It would have
to be purged in an emergency circumstance.

k...@attt.bizz

unread,
Feb 24, 2013, 4:58:36 PM2/24/13
to
Fuel cells are *not* "rechargeable", in the battery sense.

>Don't know if such a thing
>would be a suitable replacement. Hydrogen is flammable. It would have
>to be purged in an emergency circumstance.

That would be a pretty dumb design since these batteries' whole
purpose in life are emergency circumstances.

Sylvia Else

unread,
Feb 24, 2013, 7:57:18 PM2/24/13
to
On 25/02/2013 5:30 AM, John Larkin wrote:
> On Sat, 23 Feb 2013 20:21:45 -0800, josephkk <joseph_...@sbcglobal.net>
>
> Seems like bad economics to ground a fleet of roughly $200 million planes to
> save about 1000 pounds per.
>

Though that was never the intent. If they had a certificated and
functional substitute that could be installed now to get the aircraft
back into the air, no doubt they'd do it, even if the battery weighed
1000 pounds more. But, of course, they don't have one.

Sylvia.

John Larkin

unread,
Feb 24, 2013, 8:55:37 PM2/24/13
to
On Mon, 25 Feb 2013 11:57:18 +1100, Sylvia Else <syl...@not.at.this.address>
wrote:
If they don't have a parallel plan running for NiCads or something, they are
betting big time.

Martin Brown

unread,
Feb 25, 2013, 2:59:43 AM2/25/13
to
I am with John on this one.

Sodium sulphur batteries have been going to be the next great thing
since the 1980's. I knew someone who worked on them - they were lethal!

High energy density *is* inherently dangerous - and even more so when
both components of the stored chemical energy are kept inside the same
physical space as in a battery. Lithium cells are particularly volatile
and are well known to have caused trouble in consumer laptops.

Even petrol (US gas) which is an everyday consumer item is very much
more dangerous than the average member of the public can grasp. This
leads to very sad accidents when people do silly things with it.

--
Regards,
Martin Brown

Yzordderrex

unread,
Feb 25, 2013, 10:52:12 AM2/25/13
to
On Monday, February 25, 2013 2:59:43 AM UTC-5, Martin Brown wrote:
> On 24/02/2013 04:21, josephkk wrote:
>
> > On Fri, 22 Feb 2013 07:37:56 -0800, John Larkin
>
> > wrote:
>
> >
>
> >> On Fri, 22 Feb 2013 14:56:06 +1100, Sylvia Else
>
> >> wrote:
>
> >>
>
> >>> On 22/02/2013 2:49 PM, cameo wrote:
>
> >>>> Boeing has a hell of a time with fixing its battery problem on the 787
>
> >>>> Dreamliner. I wonder if any of you had a deeper knowledge as to the
>
> >>>> cause and whether those batteries are just not yet a proven technology.
>
> >>>
>
> >>> I think it's more just that they're an inherently unstable technology.
>
> >>
>
> >> High energy density is inherently dangerous.
>
> >
>
> > I do not exactly agree with inherently dangerous. I say inherently
>
> > difficult (to damn difficult) to do safely. See sodium-sulphur batteries.
>
> > ?-)
>
>
>
> I am with John on this one.
>
>
>
> Sodium sulphur batteries have been going to be the next great thing
>
> since the 1980's. I knew someone who worked on them - they were lethal!
>
>
>
> High energy density *is* inherently dangerous - and even more so when
>
> both components of the stored chemical energy are kept inside the same
>
> physical space as in a battery. Lithium cells are particularly volatile
>
> and are well known to have caused trouble in consumer laptops.
>
>
>
> Even petrol (US gas) which is an everyday consumer item is very much
>
> more dangerous than the average member of the public can grasp. This
>
> leads to very sad accidents when people do silly things with it.
>
>
>
> --
>
> Regards,
>
> Martin Brown

Whatever happened to the carbon-sulphur-potassium nitrate battery? I'm sure that would be a magnitude safer than the cobalt based unit my buddies are putting together back in Tucson.

Sylvia Else

unread,
Feb 25, 2013, 5:58:47 PM2/25/13
to
Too much damage to the connected equipment due to excessive power output
variation.

Sylvia.

rickman

unread,
Feb 25, 2013, 6:16:11 PM2/25/13
to
On 2/22/2013 10:37 AM, John Larkin wrote:
> On Fri, 22 Feb 2013 14:56:06 +1100, Sylvia Else<syl...@not.at.this.address>
> wrote:
>
>> On 22/02/2013 2:49 PM, cameo wrote:
>>> Boeing has a hell of a time with fixing its battery problem on the 787
>>> Dreamliner. I wonder if any of you had a deeper knowledge as to the
>>> cause and whether those batteries are just not yet a proven technology.
>>
>> I think it's more just that they're an inherently unstable technology.
>
> High energy density is inherently dangerous.

You mean like in gasoline and jet fuel?

--

Rick

Sylvia Else

unread,
Feb 25, 2013, 6:43:13 PM2/25/13
to
The latter do at least require a supply of oxygen before anything
untoward can happen, whereas a battery has everything in place to start
emitting heat if some internal fault occurs.

An ideal battery chemistry would self-limit its power output when it
warms up so that it cannot suffer thermal runaway.

Sylvia.


k...@attt.bizz

unread,
Feb 25, 2013, 8:06:06 PM2/25/13
to
If you stored LOX in the same tank, then yes, just like that.

John Larkin

unread,
Feb 25, 2013, 8:55:10 PM2/25/13
to
On Mon, 25 Feb 2013 18:16:11 -0500, rickman <gnu...@gmail.com> wrote:

And explosives, superheated water, stretched bungee cords, rapidly
spinning things, stuff like that.

When planes crash, they tend to incinerate the occupants.

Gasoline in tanks is pretty safe, because the vapors are mostly
gasoline (or, lately, nitrogen) and there's no ignition source handy.
A high energy battery has all the nasty bits close together.


--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro acquisition and simulation

Uwe Hercksen

unread,
Feb 27, 2013, 7:25:38 AM2/27/13
to


John Larkin schrieb:

> If they don't have a parallel plan running for NiCads or something, they are
> betting big time.

Hello,

NiCads with the same energy stored would be heavier and larger than
those lithium cells used before. A reconstruction of the battery
compartment and the airplane structure around this compartment may be
necessary.

Bye

Martin Brown

unread,
Feb 27, 2013, 7:38:48 AM2/27/13
to
On 25/02/2013 01:55, John Larkin wrote:
> On Mon, 25 Feb 2013 11:57:18 +1100, Sylvia Else <syl...@not.at.this.address>
> wrote:
>
>> On 25/02/2013 5:30 AM, John Larkin wrote:
>>> On Sat, 23 Feb 2013 20:21:45 -0800, josephkk <joseph_...@sbcglobal.net>
>>>
>>> Seems like bad economics to ground a fleet of roughly $200 million planes to
>>> save about 1000 pounds per.
>>>
>>
>> Though that was never the intent. If they had a certificated and
>> functional substitute that could be installed now to get the aircraft
>> back into the air, no doubt they'd do it, even if the battery weighed
>> 1000 pounds more. But, of course, they don't have one.
>>
>> Sylvia.
>
> If they don't have a parallel plan running for NiCads or something, they are
> betting big time.

I think you mean past tense "were" betting big time and cocked it up.

Though the failure mode appears to have been a combo of bad wiring
harness and inability of the battery unit to protect itself from bad
external connections coupled with the volatile lithium cell chemistry.

Given that laptop and phone makers already knew enough to put defensive
failsafe protection into these batteries it seems astonishing that
aerospace designers on a civilian plane did not. It isn't like lithium
cells have a glowing reputation for reliability and robustness either.

http://www.electronicsweekly.com/blogs/engineering-design-problems/2007/09/whats-wrong-with-lithiumion-ba-1.html

There have been plenty of serious recalls of kit with dodgy lithium
batteries where inadequate protection could lead to self immolation!

--
Regards,
Martin Brown

josephkk

unread,
Feb 27, 2013, 9:01:38 PM2/27/13
to
I am proposing they are inherently damn difficult to do safely. It is a
similar concept.

?-)

josephkk

unread,
Feb 27, 2013, 9:09:27 PM2/27/13
to
On Sun, 24 Feb 2013 10:30:06 -0800, John Larkin
I think you have half of a good point with the zinc-air batteries. Good
energy density, indefinite shelf life, but one use only. Given the use
involved that might not be inappropriate. OTOH at 38,000 feet the air is
rather a bit thinner, and the gradient on the way down is noticeable.
Designing a zinc-air battery for the required performance with that change
in conditions may be very challenging, of course you could add bottled air
at altitude, but that carries other problems with it.

?-)

Jasen Betts

unread,
Feb 28, 2013, 1:01:02 AM2/28/13
to
use bleed air from the jet engines, same as is used for cabin pressure.




--
⚂⚃ 100% natural

k...@attt.bizz

unread,
Feb 28, 2013, 12:44:19 PM2/28/13
to
As long as you _have_ engines, why not just use their electrical
systems?

who where

unread,
Feb 28, 2013, 7:20:26 PM2/28/13
to
On 28 Feb 2013 06:01:02 GMT, Jasen Betts <ja...@xnet.co.nz> wrote:

exc ept if you are trying a mid-air restart and need the APU run up to
achieve it, you won't have bleed air available.

bloggs.fred...@gmail.com

unread,
Feb 28, 2013, 7:33:11 PM2/28/13
to
On Thursday, February 28, 2013 7:20:26 PM UTC-5, who where wrote:

>
> exc ept if you are trying a mid-air restart and need the APU run up to
>
> achieve it, you won't have bleed air available.

They have an air-driven turbine generator they deploy below the fuselage to provide even more backup. They even had to use it once in test flights when they had a massive console fire in the cock pit.

Uwe Hercksen

unread,
Mar 1, 2013, 4:27:09 AM3/1/13
to


Martin Brown schrieb:

> Given that laptop and phone makers already knew enough to put defensive
> failsafe protection into these batteries it seems astonishing that
> aerospace designers on a civilian plane did not. It isn't like lithium
> cells have a glowing reputation for reliability and robustness either.

Hello,

there is an important difference. If something goes wrong with the
lithium cells in a laptop or phone, it is acceptable to do an emergency
shut off of the device.
If the lithium cells in a plane overheat, emergency power must be
maintained, you cant switch of the cells. Emergency power from these
cells must be available until a save landing has been done. The only
alternative is to switch to a second or third set of cells.

Bye

Uwe Hercksen

unread,
Mar 1, 2013, 4:30:47 AM3/1/13
to


Jasen Betts schrieb:

> use bleed air from the jet engines, same as is used for cabin pressure.

Hello,

bad idea. These batteries must maintain emergency power in the case all
jet engines are not running.

Bye

who where

unread,
Mar 1, 2013, 8:07:35 PM3/1/13
to
Yep, I'm aware of the RAT.

josephkk

unread,
Mar 1, 2013, 10:38:16 PM3/1/13
to
On 28 Feb 2013 06:01:02 GMT, Jasen Betts <ja...@xnet.co.nz> wrote:

IIRC these things are for complete power loss, the jet engines aren't
operating. But the oxygen system for the passengers could be tapped i
suppose.

?-)

k...@attt.bizz

unread,
Mar 1, 2013, 11:06:54 PM3/1/13
to
On Fri, 01 Mar 2013 19:38:16 -0800, josephkk
Isn't the passengers' oxygen system there to avoid nasty law suits?

legg

unread,
Mar 17, 2013, 12:15:35 AM3/17/13
to
On Thu, 21 Feb 2013 19:49:44 -0800, cameo <ca...@unreal.invalid>
wrote:

>Boeing has a hell of a time with fixing its battery problem on the 787
>Dreamliner. I wonder if any of you had a deeper knowledge as to the
>cause and whether those batteries are just not yet a proven technology.

Preliminary:

Power for the safety valves, in case of smoke, was the APU.

The APU shut down but somehow the contactor was still closed upon
inspection.

http://www.ntsb.gov/investigations/2013/boeing_787/interim_report_B787_3-7-13.pdf

RL
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