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Lithium Battery destroys a NASA robot

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rampil

Joined: 04 May 2007
Posts: 870

Posted: Fri Oct 28, 2016 8:02 am Post subject: Lithium Battery destroys a NASA robot

Adding a log to the fire   

Weight savings isn't always the only consideration in aircraft design!



https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/

_________________
Ira N224XS

ceengland7(at)gmail.com
Guest

Posted: Fri Oct 28, 2016 9:55 am Post subject: Lithium Battery destroys a NASA robot

And  continuing with that logic,

https://en.wikipedia.org/wiki/RocketMotorTwo

we should all convert our planes to gliders, since there was a fuel 

explosion somewhere.



Caution in aviation is a good idea, but worrying about the wrong problem 

doesn't help. (Virtually no one thinks using Lithium Ion batteries for 

primary electrical power in a homebuilt is a good idea.)



Charlie



On 10/28/2016 11:02 AM, rampil wrote:

 	  Quote: 	
		   



 Adding a log to the fire  

 Weight savings isn't always the only consideration in aircraft design!



 https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/



 --------

 Ira N224XS

kenryan

Joined: 20 Oct 2009
Posts: 429

Posted: Fri Oct 28, 2016 10:17 am Post subject: Lithium Battery destroys a NASA robot

Not sure where you came up with that one. Nearly everyone I know with an experimental is now using a lithium battery (and a few certified guys on the sly).

 

Sent from my Android. Sorry Steve. 

On Oct 28, 2016 10:02 AM, "Charlie England" <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote: 	  Quote: 	
		  --> AeroElectric-List message posted by: Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>

 

 And  continuing with that logic,

 https://en.wikipedia.org/wiki/RocketMotorTwo

 we should all convert our planes to gliders, since there was a fuel explosion somewhere.

 

 Caution in aviation is a good idea, but worrying about the wrong problem doesn't help. (Virtually no one thinks using Lithium Ion batteries for primary electrical power in a homebuilt is a good idea.)

 

 Charlie

 

 On 10/28/2016 11:02 AM, rampil wrote:

  	  Quote: 	
		   --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

 

 Adding a log to the fire  

 Weight savings isn't always the only consideration in aircraft design!

 

 https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/

 

 --------

 Ira N224XS

 

 	
 

 

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ceengland7(at)gmail.com
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Posted: Fri Oct 28, 2016 10:50 am Post subject: Lithium Battery destroys a NASA robot

Maybe, but I strongly doubt that they       are using a Lithium *ION* battery for their primary battery in       their a/c. They are almost certainly using Lithium Iron Phosphate       batteries (with built-in battery management). If they really are       using Lithium *ION* batteries, then they really do need to see the       video that Ira posted.

       

 https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=lithium%20ion%20vs%20lithium%20iron

       

       There are many different battery chemistries that include lithium       in the mix; and they can have very different characteristics.

       

       Charlie 

       

       On 10/28/2016 1:16 PM, Ken Ryan wrote:

     

      	  Quote: 	
		         

Not sure where you came up with that one. Nearly         everyone I know with an experimental is now using a lithium         battery (and a few certified guys on the sly).

              

Sent from my Android. Sorry Steve.       

         On Oct 28, 2016 10:02 AM, "Charlie           England" <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>           wrote:            	  Quote: 	
		  -->             AeroElectric-List message posted by: Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>

             

             And  continuing with that logic,

             https://en.wikipedia.org/wiki/RocketMotorTwo

             we should all convert our planes to gliders, since there was             a fuel explosion somewhere.

             

             Caution in aviation is a good idea, but worrying about the             wrong problem doesn't help. (Virtually no one thinks using             Lithium Ion batteries for primary electrical power in a             homebuilt is a good idea.)

             

             Charlie

             

             On 10/28/2016 11:02 AM, rampil wrote:

              	  Quote: 	
		                 --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

               

               Adding a log to the fire  

               Weight savings isn't always the only consideration in               aircraft design!

               

               https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/

               

               --------

               Ira N224XS

               

             	
             

             

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yellowduckduo(at)gmail.co
Guest

Posted: Fri Oct 28, 2016 10:51 am Post subject: Lithium Battery destroys a NASA robot

Don't confuse Lithium ION with newer, safer, Lithium IRON phosphate 

despite the similar sounding names.

Ken



On 28/10/2016 2:16 PM, Ken Ryan wrote:

 	  Quote: 	
		  

 Not sure where you came up with that one. Nearly everyone I know with 

 an experimental is now using a lithium battery (and a few certified 

 guys on the sly).



 Sent from my Android. Sorry Steve.

 On Oct 28, 2016 10:02 AM, "Charlie England" <ceengland7(at)gmail.com 

 <mailto:ceengland7(at)gmail.com>> wrote:



     

     <ceengland7(at)gmail.com <mailto:ceengland7(at)gmail.com>>



     And  continuing with that logic,

     https://en.wikipedia.org/wiki/RocketMotorTwo

     <https://en.wikipedia.org/wiki/RocketMotorTwo>

     we should all convert our planes to gliders, since there was a

     fuel explosion somewhere.

     

     Caution in aviation is a good idea, but worrying about the wrong

     problem doesn't help. (Virtually no one thinks using Lithium Ion

     batteries for primary electrical power in a homebuilt is a good idea.)



     Charlie



     On 10/28/2016 11:02 AM, rampil wrote:



         

         <ira.rampil(at)gmail.com <mailto:ira.rampil(at)gmail.com>>



         Adding a log to the fire  

         Weight savings isn't always the only consideration in aircraft

         design!



         https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/

         <https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/>



         --------

         Ira N224XS



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lyleapgmc

Joined: 19 Feb 2014
Posts: 57

Posted: Fri Oct 28, 2016 11:01 am Post subject: Lithium Battery destroys a NASA robot

The headline distorts the facts.  Yes, lithium batteries will cumbust if 

they aren't handled properly and carefully.  So too will dynamite 

explode if not handled carefully.  Gasoline vapors will burn if an 

ignition source is provided.  Lead/acid batteries will explode.



There is a control circuit built in to lithium battery packs that 

monitors the voltage and the cell temperature.  It is there for a very 

good reason -  To reduce the likelihood of a cell being overcharged or 

overheated and thus starting to burn.  The next time the battery in your 

laptop fails completely take it apart, carefully.  You will find a small 

circuit board in the battery. It is connected to each set of paralleled 

cells.  There is also a thermistor connected to the board that monitors 

the pack temperature.  It is this control that the engineers forgot to 

enable.



It is also dangerous to go to bed.  People die there.  So too it is 

dangerous to get up in the morning.  "Let's be careful out there."

On 10/28/2016 11:02 AM, rampil wrote:

 	  Quote: 	
		   



 Adding a log to the fire  

 Weight savings isn't always the only consideration in aircraft design!



 https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/



 --------

 Ira N224XS





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=461683#461683

kenryan

Joined: 20 Oct 2009
Posts: 429

Posted: Fri Oct 28, 2016 11:20 am Post subject: Lithium Battery destroys a NASA robot

It is my understanding that all of the lithium batteries (including LiFePO) fall under the general category of "lithium ion." My source is Battery University, here:



http://batteryuniversity.com/learn/article/lithium_based_batteries



and here:

http://batteryuniversity.com/learn/article/types_of_lithium_ion



Ken





On Fri, Oct 28, 2016 at 10:49 AM, Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote:

 	  Quote: 	
		                     Maybe, but I strongly doubt that they       are using a Lithium *ION* battery for their primary battery in       their a/c. They are almost certainly using Lithium Iron Phosphate       batteries (with built-in battery management). If they really are       using Lithium *ION* batteries, then they really do need to see the       video that Ira posted.

       

 https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=lithium%20ion%20vs%20lithium%20iron

       

       There are many different battery chemistries that include lithium       in the mix; and they can have very different characteristics.

       

       Charlie 

       

       On 10/28/2016 1:16 PM, Ken Ryan wrote:

     

      	  Quote: 	
		         

Not sure where you came up with that one. Nearly         everyone I know with an experimental is now using a lithium         battery (and a few certified guys on the sly).

              

Sent from my Android. Sorry Steve.       

         On Oct 28, 2016 10:02 AM, "Charlie           England" <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>           wrote:            	  Quote: 	
		  -->             AeroElectric-List message posted by: Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>

             

             And  continuing with that logic,

             https://en.wikipedia.org/wiki/RocketMotorTwo

             we should all convert our planes to gliders, since there was             a fuel explosion somewhere.

             

             Caution in aviation is a good idea, but worrying about the             wrong problem doesn't help. (Virtually no one thinks using             Lithium Ion batteries for primary electrical power in a             homebuilt is a good idea.)

             

             Charlie

             

             On 10/28/2016 11:02 AM, rampil wrote:

              	  Quote: 	
		                 --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

               

               Adding a log to the fire  

               Weight savings isn't always the only consideration in               aircraft design!

               

               https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/

               

               --------

               Ira N224XS

               

             	
             

             

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             eferrer" target="_blank">http://forums.matronics.com

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             ====================================

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Oct 28, 2016 11:54 am Post subject: Lithium Battery destroys a NASA robot

At 11:02 AM 10/28/2016, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com>



 Adding a log to the fire   

 Weight savings isn't always the only consideration in aircraft design! 	


   . . . a point I've tried to illuminate for several

   years. In the articles I did for Kit Planes on batteies,

   a question I posed to owner/ops of OBAM aircraft asked

   them to consider: "suppose you DO take 10 pounds out

   of the empty weight of your aircraft . . . now what?"



   By how many feet will this reduce landing/takeoff roll?



   By how many feet/min will this increase rated of climb?



   By what amount will this increase cruising speed, fuel

   efficiency or service ceiling?



   If 10 pounds comes off the airframe, will the fuel

   capacity grow by 10 pounds?



   Next to last, whan was the last time you delay launch

   into the wild blue to off-load fuel or luggage

   because you were . . . say . . . 20# over gross?



   Finally, what is the return on investment for having

   expended $xxx versus $yyy in the selection of your

   flight battery. Consider the economics of having

   to be more cognizant of the $xxx battery's special

   vulnerabilities for inadvertent, permanent damage

   thus trashing what ever service life remained.



   Burt Rutan went through hundreds of similar

   weight effects analysis decisions because

   his mission aircraft tool 5 pounds of fuel

   to carry one pound of airplane around the world.

   One pound of empty weight reduction was a 6

   pound reduction of takeoff weight. But the

   battery in our airplane is but one of few

   opportunities for weight reduction . . . with

   costs that may well be difficult if not

   impossible to justify economically.



   To be sure, there are numerous Lithium products

   crafted for use in airplanes demonstrated to

   present little or no risk over their lead-acid

   counterpart. But NASA robots, hoverboards, cell

   phones, laptops, etc. are different markets

   with trade-offs in design that have nothing

   to do with aircraft. The aviation battery market

   is infinitely more sophisticated than for

   those factories that power up fire-prone

   hoverboards . . .



  http://tinyurl.com/zdlf65d



   . . . so it's up to US to evaluate the potential

   benefit/risk ratio for bolting a new battery

   into our airplane. Do it for reasons that

   make good sense to you and KNOW your

   supplier. Right now, LiIPo is the chemistry

   of choice paired with capable battery

   management electronics not unlike EarthX,

   TrueBlue and no doubt, others. 



   In my not so humble opinion, whoever was in

   charge of the battery system on that NASA

   robot project should be VERY carefully

   screened at his/her next performance review.



   I could tell some tales too on individuals

   with poor judgement on alternator selection

   for another taxpayer funded project . . .

   



 

 

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Oct 28, 2016 12:39 pm Post subject: Lithium Battery destroys a NASA robot

At 01:59 PM 10/28/2016, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: Lyle Peterson <lyleap(at)centurylink.net>



 The headline distorts the facts.  Yes, lithium batteries will cumbust if they aren't handled properly and carefully.  So too will dynamite explode if not handled carefully.  Gasoline vapors will burn if an ignition source is provided.  Lead/acid batteries will explode. 	


  Agreed. I've often suggested that the step

  up from lead-acid to lithium was akin to figuring

  out how to burn nitroglycerin in our engine. Great

  power to weight ratio but with practical problems.



 

  	  Quote: 	
		  There is a control circuit built in to lithium battery packs that monitors the voltage and the cell temperature.  It is there for a very good reason -  To reduce the likelihood of a cell being overcharged or overheated and thus starting to burn. 	


  It's not an automatic thing. I've dissected

  the little 'pillow' batteries used in my

  grand-children's helicopters and found

  tiny etched circuit boards of unknown quality

  or performance . . . but yes, there was some

  form of electronic 'smarts'.



  At the same time, there are manufacturers of

  all manner of lithium products who may or may

  not include such features . . . perhaps expecting

  the system integrator to add the necessary

  electronics. 



  The TrueBlue certified batteries are huge arrays

  of cylindrical cells . . . manufactured by A123

  if memory serves. I'm pretty sure these cells are

  raw chemistry with no 'smarts'. I'll dissect some

  18650 cells I have on hand one of these days and

  see what's inside them . . . at MOST it will be

  a fuse or other current limiting device. there

  is NO protection for over discharge or over charge.



  I'm pretty sure there's no 'smarts' in an AeroVolts

  product and there have been a few 'melt downs' that

  behaved more like burning enclosures than of a

  lithium fed fire.



  The word 'lithium' is only a imperative to inquire

  deeper into how it is compounded and implemented

  from the system perspective. Further, 'news'

  stories about exploding batteries have little

  if any relevance to our deliberations. Yeah,

  lithium has some risks as does gasoline or

  even lead-acid. The trick is to reduce those

  risks in a manner that would make Walter Beech

  or Duane Wallace proud.



 

 

   Bob . . .

argoldman(at)aol.com
Guest

Posted: Fri Oct 28, 2016 1:07 pm Post subject: Lithium Battery destroys a NASA robot

Not so sure you are correct about that last statement. Perhaps that is your own prejudice. 

Additionally everybody seems to be lumping lithium batteries in one groups independent of the fact that there are various chemistries each involving lithium but each with its unique power density and safety. 

It would be a great idea if when talking(writing) that the specific type of chemistry of the battery is stated so that the conversation begins to have some real meaning. 

Rich

Sent from my iPhone

 	  Quote: 	
		   On Oct 28, 2016, at 12:54 PM, Charlie England <ceengland7(at)gmail.com> wrote:

 And  continuing with that logic,

 https://en.wikipedia.org/wiki/RocketMotorTwo

 we should all convert our planes to gliders, since there was a fuel explosion somewhere.

 Caution in aviation is a good idea, but worrying about the wrong problem doesn't help. (Virtually no one thinks using Lithium Ion batteries for primary electrical power in a homebuilt is a good idea.)

 Charlie

> On 10/28/2016 11:02 AM, rampil wrote:

> 

> 

> Adding a log to the fire  

> Weight savings isn't always the only consideration in aircraft design!

> 

> https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/

> 

> --------

> Ira N224XS

>

ceengland7(at)gmail.com
Guest

Posted: Fri Oct 28, 2016 1:51 pm Post subject: Lithium Battery destroys a NASA robot

I suppose you could make a case for that; lithium ions are likely participants in all the various chemistries. However, the only chemistry that seems to be in common use for starting and primary reserve energy in homebuilts isLithium Iron Phosphate(LiFePO4)If you look at the links in the google search I referenced earlier, the FePLiO4 typically compared to 'lithium ion' when evaluating suitability and safety. (ex: http://www.brighthubengineering.com/power-generation-distribution/123906-comparison-of-lithium-ion-to-lithium-iron-battery/) Technically, the 'lithium ion' they are talking about is likely to be lithium cobalt or lithium manganese. But colloquial terms are typically 'lithium ion' vs 'lithium iron' when discussing them. While it's possible that NASA was using lithium iron in that robot and the reporter used the catchall 'lithium ion' to describe it, it's more likely it was something other than lithium iron phosphate (probably lithium cobalt).

Understand, I'm not advocating the use of FePLiO4; For me, it's still too expensive (and still a bit more risky) than a regular SLA. But I wouldn't be terrified to fly with someone using one. Not sure I could say the same for a lithium ion (cobalt or manganese) battery.

Does that help?

Charlie

On Fri, Oct 28, 2016 at 2:19 PM, Ken Ryan <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote:

 	  Quote: 	
		  It is my understanding that all of the lithium batteries (including LiFePO) fall under the general category of "lithium ion." My source is Battery University, here:



http://batteryuniversity.com/learn/article/lithium_based_batteries



and here:

http://batteryuniversity.com/learn/article/types_of_lithium_ion



Ken





On Fri, Oct 28, 2016 at 10:49 AM, Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote:

 	  Quote: 	
		                     Maybe, but I strongly doubt that they       are using a Lithium *ION* battery for their primary battery in       their a/c. They are almost certainly using Lithium Iron Phosphate       batteries (with built-in battery management). If they really are       using Lithium *ION* batteries, then they really do need to see the       video that Ira posted.

       

 https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=lithium%20ion%20vs%20lithium%20iron

       

       There are many different battery chemistries that include lithium       in the mix; and they can have very different characteristics.

       

       Charlie 

       

       On 10/28/2016 1:16 PM, Ken Ryan wrote:

     

      	  Quote: 	
		         

Not sure where you came up with that one. Nearly         everyone I know with an experimental is now using a lithium         battery (and a few certified guys on the sly).

              

Sent from my Android. Sorry Steve.       

         On Oct 28, 2016 10:02 AM, "Charlie           England" <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>           wrote:            	  Quote: 	
		  -->             AeroElectric-List message posted by: Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>

             

             And  continuing with that logic,

             https://en.wikipedia.org/wiki/RocketMotorTwo

             we should all convert our planes to gliders, since there was             a fuel explosion somewhere.

             

             Caution in aviation is a good idea, but worrying about the             wrong problem doesn't help. (Virtually no one thinks using             Lithium Ion batteries for primary electrical power in a             homebuilt is a good idea.)

             

             Charlie

             

             On 10/28/2016 11:02 AM, rampil wrote:

              	  Quote: 	
		                 --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

               

               Adding a log to the fire  

               Weight savings isn't always the only consideration in               aircraft design!

               

               https://www.engadget.com/2016/10/28/lithium-battery-failure-wipes-out-darpa-robot-at-nasa/

               

               --------

               Ira N224XS

               

             	
             

             

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bobsv35b(at)aol.com
Guest

Posted: Fri Oct 28, 2016 2:33 pm Post subject: Lithium Battery destroys a NASA robot

Good Evening Bob,   

 

  As usual, very informative! 

 

  Happy Skies,

  

 

  Old Bob

 

  --

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Oct 28, 2016 2:41 pm Post subject: Lithium Battery destroys a NASA robot

At 01:59 PM 10/28/2016, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: Lyle Peterson <lyleap(at)centurylink.net>



 The headline distorts the facts.  Yes, lithium batteries will cumbust if they aren't handled properly and carefully.  So too will dynamite explode if not handled carefully.  Gasoline vapors will burn if an ignition source is provided.  Lead/acid batteries will explode. 	


  Agreed. I've often suggested that the step

  up from lead-acid to lithium was akin to figuring

  out how to burn nitroglycerin in our engine. Great

  power to weight ratio but with practical problems.



 

  	  Quote: 	
		  There is a control circuit built in to lithium battery packs that monitors the voltage and the cell temperature.  It is there for a very good reason -  To reduce the likelihood of a cell being overcharged or overheated and thus starting to burn. 	


  It's not an automatic thing. I've dissected

  the little 'pillow' batteries used in my

  grand-children's helicopters and found

  tiny etched circuit boards of unknown quality

  or performance . . . but yes, there was some

  form of electronic 'smarts'.



  At the same time, there are manufacturers of

  all manner of lithium products who may or may

  not include such features . . . perhaps expecting

  the system integrator to add the necessary

  electronics. 



  The TrueBlue certified batteries are huge arrays

  of cylindrical cells . . . manufactured by A123

  if memory serves. I'm pretty sure these cells are

  raw chemistry with no 'smarts'. I'll dissect some

  18650 cells I have on hand one of these days and

  see what's inside them . . . at MOST it will be

  a fuse or other current limiting device. there

  is NO protection for over discharge or over charge.



  I'm pretty sure there's no 'smarts' in an AeroVolts

  product and there have been a few 'melt downs' that

  behaved more like burning enclosures than of a

  lithium fed fire.



  The word 'lithium' is only a imperative to inquire

  deeper into how it is compounded and implemented

  from the system perspective. Further, 'news'

  stories about exploding batteries have little

  if any relevance to our deliberations. Yeah,

  lithium has some risks as does gasoline or

  even lead-acid. The trick is to reduce those

  risks in a manner that would make Walter Beech

  or Duane Wallace proud.



 

 

   Bob . . .

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