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EarthX lithium

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nuckolls.bob(at)aeroelect
Guest

Posted: Mon Mar 17, 2014 8:41 am Post subject: EarthX lithium

I just became aware of EarthX batteries based on

comments here on the list. I visited their website

and studied a variety of assertions and comparisons

designed to promote sales. At first blush, these

folks are hanging their marketing hats on the same

philosophy as other suppliers of lithium technologies.



See attached document . . .



The DEARTH of good engineering data for these

products makes it difficult if not impossible to

craft a well considered integration of the current

COTS (commericial off the shelf) offerings onto

airplanes.



I had to delay submission of the last of four

Kitplanes articles for a month . . . not because

theres a paucity of choices . . . but because the

folks selling them can't define performance in

rational numbers. Still digging . . .

   Bob . . .

FAQs_about_EarthX_Lithium_Batteries.pdf

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nuckolls.bob(at)aeroelect
Guest

Posted: Mon Mar 17, 2014 8:57 am Post subject: EarthX lithium

Skip,



Had a reader recommend EarthX lithium batteries for airplanes.

Seems they're courting Van's and some other suppliers of

kit aircraft and parts.



Downloaded a page of their marketing pitch. I commented on

it and published it back to my forum.



I'm going to contact EarthX for more information on ENERGY

numbers and a functional description of their 'battery

management system'.



See attached . . .

   Bob . . .

FAQs_about_EarthX_Lithium_Batteries.pdf

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rlborger(at)mac.com
Guest

Posted: Mon Mar 17, 2014 9:46 am Post subject: EarthX lithium

Bob N,



In your commentary on the FAQ.  At the end there is a question about deeply discharging the battery.  Your comment is “So if I go off and leave the master switch ON, odds are that by the time I get back to fly again, my battery is trash?  



I can answer that in one word - YES.  Your battery is trash.  



If this battery is like the one I purchased to test, it does not have a “BMS” which auto-disconnects to protect cells from over-discharge.



I flew with this battery for several months and did some simple ground testing.  Tested things like - How long would it last running all the electrics (EIS, EFIS, radio & transponder), how long just running the EIS, radio & transponder, how long just running the EIS & radio and how long just running the EIS & transponder?  After each test I put the high-tech charger on and recharged with the cell balance in effect.  I didn’t get to the last of the questions because after the EIS, radio & transponder test I managed to put the charger on but left the Master on as well.  When I came back a couple days later to continue the testing the battery was fully discharged and would not accept recharging.  It was trashed.



FYI, in testing the battery I found that it would run the whole electrical system about 5 minutes.  It would run the EIS, radio & transponder about 7 minutes.  



Overall, I was not impressed with the LiFePo battery.  It was extremely light and it started my Rotax 914 quickly and easily.  After starting the engine and flying for a while, it would be properly and fully charged when back on the ground.  Unfortunately, from my limited testing, it didn’t have any real legs to run things on its own and it requires a lot of fancy, high-tech, gear to keep it happy.  And take great care not discharge it fully.



Just my 2¢ from my very limited experience.



Blue skies & tailwinds,

Bob Borger

Europa XS Tri, Rotax 914, Airmaster C/S Prop (50 hrs).

Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP

3705 Lynchburg Dr.

Corinth, TX  76208-5331

Cel: 817-992-1117

rlborger(at)mac.com



On Mar 17, 2014, at 11:40 AM, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com> wrote:



I just became aware of EarthX batteries based on

comments here on the list. I visited their website

and studied a variety of assertions and comparisons

designed to promote sales. At first blush, these

folks are hanging their marketing hats on the same

philosophy as other suppliers of lithium technologies.



See attached document . . .



The DEARTH of good engineering data for these

products makes it difficult if not impossible to

craft a well considered integration of the current

COTS (commericial off the shelf) offerings onto

airplanes.



I had to delay submission of the last of four

Kitplanes articles for a month . . . not because

theres a paucity of choices . . . but because the

folks selling them can't define performance in

rational numbers. Still digging . . .

 Bob . . . <FAQs about EarthX Lithium Batteries.pdf>

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Mar 17, 2014 10:18 am Post subject: EarthX lithium

At 12:46 PM 3/17/2014, you wrote:

 --> AeroElectric-List message posted by: Robert Borger <rlborger(at)mac.com>



 Bob N,



 In your commentary on the FAQ.  At the end there is a question about deeply discharging the battery.  Your comment is “So if I go off and leave the master switch ON, odds are that by the time I get back to fly again, my battery is trash?  



 I can answer that in one word - YES.  Your battery is trash.  



 If this battery is like the one I purchased to test, it does not have a “BMS” which auto-disconnects to protect cells from over-discharge.



         Which part number of battery did you test?



 I flew with this battery for several months and did some simple ground testing.  Tested things like - How long would it last running all the electrics (EIS, EFIS, radio & transponder), how long just running the EIS, radio & transponder, how long just running the EIS & radio and how long just running the EIS & transponder?  After each test I put the high-tech charger on and recharged with the cell balance in effect.  I didn’t get to the last of the questions because after the EIS, radio & transponder test I managed to put the charger on but left the Master on as well.  When I came back a couple days later to continue the testing the battery was fully discharged and would not accept recharging.  It was trashed.



         Good data point . . .



 FYI, in testing the battery I found that it would run the whole electrical system about 5 minutes.  It would run the EIS, radio & transponder about 7 minutes.  



 Overall, I was not impressed with the LiFePo battery.  It was extremely light and it started my Rotax 914 quickly and easily.  After starting the engine and flying for a while, it would be properly and fully charged when back on the ground.  Unfortunately, from my limited testing, it didn’t have any real legs to run things on its own and it requires a lot of fancy, high-tech, gear to keep it happy.  And take great care not discharge it fully.



 Just my 2¢ from my very limited experience.



         From your limited observations, what would you estimate

         the energy content to be for the model you tested? In

         other words, what was the demand for the EIS, radio and

          transponder?  Apparently it would satisfactorily crank

         an engine for some time.



         I have emailed EarthX requesting the name and address

         for an individual who can supply technical date in detail

         sufficient to make good system integration choices. 



         Thanks for the data points!



 



 

   Bob . . .    [quote][b]

rlborger(at)mac.com
Guest

Posted: Mon Mar 17, 2014 11:02 am Post subject: EarthX lithium

Bob N,



LiFePo battery - AeroVoltz 8 Cell Lithium Battery.  http://aerovoltz.net/en/

The Sport EFIS consumes about 1 amp according to the documentation.  I don’t have good numbers on the GRT EIS4000 but I would allow about 1 amp with all the sensors, back light, display, etc.  I may be able to get a better number next trip to the hanger.  The radio and transponder are MicroAir M760Q & T2000 SFL.  From the documentation, I’d say they each use about 250-300ma with the backlight on and not transmitting.

The battery turned the 914 over very smartly.  The engine is easy to start in any case so it wasn’t really working that hard.  Three or 4 prop blades and it starts.  That’s 2 or 3 rotations of the engine.

Blue skies & tailwinds,Bob BorgerEuropa XS Tri, Rotax 914, Airmaster C/S Prop (50 hrs).Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP3705 Lynchburg Dr.Corinth, TX  76208-5331Cel: 817-992-1117rlborger(at)mac.com (rlborger(at)mac.com)



On Mar 17, 2014, at 1:17 PM, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:

  At 12:46 PM 3/17/2014, you wrote:

 --> AeroElectric-List message posted by: Robert Borger <rlborger(at)mac.com (rlborger(at)mac.com)>



 Bob N,



 In your commentary on the FAQ.  At the end there is a question about deeply discharging the battery.  Your comment is “So if I go off and leave the master switch ON, odds are that by the time I get back to fly again, my battery is trash?  



 I can answer that in one word - YES.  Your battery is trash.  



 If this battery is like the one I purchased to test, it does not have a “BMS” which auto-disconnects to protect cells from over-discharge.



         Which part number of battery did you test?



 I flew with this battery for several months and did some simple ground testing.  Tested things like - How long would it last running all the electrics (EIS, EFIS, radio & transponder), how long just running the EIS, radio & transponder, how long just running the EIS & radio and how long just running the EIS & transponder?  After each test I put the high-tech charger on and recharged with the cell balance in effect.  I didn’t get to the last of the questions because after the EIS, radio & transponder test I managed to put the charger on but left the Master on as well.  When I came back a couple days later to continue the testing the battery was fully discharged and would not accept recharging.  It was trashed.



         Good data point . . .



 FYI, in testing the battery I found that it would run the whole electrical system about 5 minutes.  It would run the EIS, radio & transponder about 7 minutes.  



 Overall, I was not impressed with the LiFePo battery.  It was extremely light and it started my Rotax 914 quickly and easily.  After starting the engine and flying for a while, it would be properly and fully charged when back on the ground.  Unfortunately, from my limited testing, it didn’t have any real legs to run things on its own and it requires a lot of fancy, high-tech, gear to keep it happy.  And take great care not discharge it fully.



 Just my 2¢ from my very limited experience.



         From your limited observations, what would you estimate

         the energy content to be for the model you tested? In

         other words, what was the demand for the EIS, radio and

          transponder?  Apparently it would satisfactorily crank

         an engine for some time.



         I have emailed EarthX requesting the name and address

         for an individual who can supply technical date in detail

         sufficient to make good system integration choices. 



         Thanks for the data points!



 



 

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Mar 18, 2014 2:31 am Post subject: EarthX lithium

At 02:01 PM 3/17/2014, you wrote:

 Bob N,



 LiFePo battery - AeroVoltz 8 Cell Lithium Battery.   http://aerovoltz.net/en/



 The Sport EFIS consumes about 1 amp according to the documentation.  I don’t have good numbers on the GRT EIS4000 but I would allow about 1 amp with all the sensors, back light, display, etc.  I may be able to get a better number next trip to the hanger.  The radio and transponder are MicroAir M760Q & T2000 SFL.  From the documentation, I’d say they each use about 250-300ma with the backlight on and not transmitting.



 The battery turned the 914 over very smartly.  The engine is easy to start in any case so it wasn’t really working that hard.  Three or 4 prop blades and it starts.  That’s 2 or 3 rotations of the engine.



    Okay, that's not an EarthX battery which

    claims to have a battery management system

    built in.



    From the physical sizes of these batteries,

    I suspect they are assembled from individual

    cells not unlike the 26650 styles offered by

    A123 and others.



  http://tinyurl.com/ktyfbnp



    These would be 'rated' at something on the

    order of 2.3 to 2.5aH per  cell. A  2-row,

    8-cell assembly would offer a 12V battery

    with a capacity on the order of 5aH. A number

    which is inconsistent with your battery

    only endurance experience.



    Their 16-cell product would have a cell weight

    of 75g x 16 or 1.2Kg. Their catalog weight for

    the 16 cell product is 1.6Kg which leaves 0.4Kg

    for enclosure . . . sounds about right. So

    their 16-cell product would clock in with a 10aH

    legacy rating and 1.2Kg x 125Wh/Kg or 150Wh

    of total energy.



    Given the relatively flat discharge curves of

    lithium chemistries (low internal impedance) one

    might estimate that 125Wh will be available at

    a 10A discharge rate. So it seems that the 16-cell

    device would run a 100W demand engine for 1.2 hours

    when new and 1 hour at end of life.



    Let's get some hard numbers on the current draw

    for your experiments and see why you didn't get

    better performance from your '5aH' product.



    Aerovolts doesn't claim to offer an

    internal BMS but they do offer the external

    BMS charger with words like:

 ------------------------------------

 The Aerovoltz  Battery Management System Balance Charger is the only charger on the market designed specifically to work with the Aerovoltz battery. The primary advantage to the Aerovoltz BMS Blance Charger is the balance charging function. The Balance mode balances the voltage of each cell or cell pack while charging. By balance charging your Aerovoltz Performance Battery you insure that the battery is operating at its maximum power. Periodic balance charging can also double the expected life of your battery. This charger is not required to operate your Battery, but it is highly recommended.



         The only charger made to work with the  Battery Management System. 



         Plugs directly into the batteries BMS port. 



         Able to balance charge all the cells individually for max power and durability. 



         Can double the expected life of the  battery. 



         Has Charge, Fast Charge, Balance Charge, and Storage Charge Functions. 



         Available in 120V (US) and 240V (EUR). 

 -------------------------------------

    The problem I have with these special chargers is

    rooted in the fact that when we put an airplane away,

    the battery is generally topped off . . . 



    It's my understanding that these super-smart chargers

    work their magic while recharging a partially to

    completely depleted battery. How then would such a

    charger benefit the OBAM aircraft owner/operator?

    . . . and DOUBLE the life of the battery? THAT'S

    a VERY LONG POLE in the tent for cost-of-ownership

    for a battery that is already VERY expensive compared

    to the device it purports to replace.



    Aerovolts also claims:

 -----------------------------------------

 The 16 Cell has a massive 500PCA and 28 Pbeq AHs at only 3 lbs of weight. The 16 Cell is a direct replacement of the Yuasa YTX30L-BS, GYZ-20HL, and YTX24HL-BS. 

 -----------------------------------------

    The Yuasa YTX30L is a 22 pound, SVLA battery that would

    clock in at about 24aH . . . I submit that while the 16-cell

    Aerovolts product may CRANK like the Yuasa battery, it is

    NOT A DIRECT REPLACEMENT when it comes to keeping the

    fires lit up front . . . in fact, it's probably less than

    half the capacity of the Yuasa battery.



 [img]cid:.0[/img]



 



    We'll keep asking questions . . .

  



 



 

   Bob . . .

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stuart(at)stuarthutchison
Guest

Posted: Wed Mar 19, 2014 11:21 pm Post subject: EarthX lithium

G'day Bob N.



Your comments in the PDF file about battery Ah rating under different

operating conditions reminded me of an interesting annecdote.



About 10 years ago, Energiser began marketing a series of cheap (approx $20)

AA battery powered chargers for cell phones.  They are a simple plastic case

(inc circuit) for two primary AA cells, plus a short adaptor cord option for

the various cell phone models.  Turns out they come fitted with lithium

cells for good reason.



 	  Quote: 	
		  From spec data sheets at the time, the rating for a standard Energiser

alkaline AA cell was typically around 2700 mAh.  The lithium cells were
	


about 3200 mAh, yet manufacturers quoted 5 to 7 times the endurance for

lithium cells in high power devices.  This seemed counter-intuitive given a

similar mAh rating.



In practice, the lithium cells can deliver higher current without the

internal resistance soaring through the roof, so most of their energy is

delivered to the load rather than wasted as heat.  It was easily proven by

replacing the AA lithium cells with alkaline cells. The alkaline cells

became too hot to touch and delivered about half a cell phone charge, while

the lithium cells delivered about 2.5 full charges. Conversely, using

lithium cells in a low power device such as a wall clock would offer a very

poor return on investment, given the lithium AA cells cost about 4 times the

price.



Cheers, Stu

--

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Mar 20, 2014 10:57 am Post subject: EarthX lithium

 	  Quote: 	
		   . . .  using lithium cells in a low power device such as a wall clock would offer a very

 poor return on investment, given the lithium AA cells cost about 4 times the

 price. 	


    Yeah, your talking about these critters . . .



 [img]cid:.0[/img]



   They're in the Size 91 package (AA) but offer a lithium-Iron

   couple that's in the same ballpark as the carbon-zinc and

   zinc-manganese flashlight cells (1.5 volts). 



   If you compare E91 alkaline cell data



 V http://tinyurl.com/nt2x8hd



   with the L91 lithium-iron data



  http://tinyurl.com/otkeubs



   We see that both products are in the same ballpark

   for contained energy but the L91 cell internal

   resistance is about 1/2 that of the E91. So not

   only do you get slightly more total energy, your

   access to that energy at high discharge rates suffers

   about 1/2 the losses in heat.



   This 'lithium' product is a different animal from

   the devices we're pondering as replacement for

   engine-cranking/standby service. The boss-hogg

   lithium cells are 3.3V couples and generally

   much lower resistance still . . .



   It's unfortunate that characteristic performance

   of two cells are not presented in the same pews . . .

   suffice it to say that the approx 1/2 internal

   resistance will toss off less energy under high

   demand loads.



   On the Nickle-Metal Hydride side of the house

   one may acquire 1.2V chemistry with very attractive

   internal impedances . . .



  http://tinyurl.com/nj5xx85



   At 1.2V vs. 1.5 volts the contained energy

   in watt-seconds suffers slightly but they'll

   readily deliver their contents at high rates.

   Down-side is that the self-discharge characteristics

   of Ni-Mh compared to the Lithium-Iron or Zinc-Manganese

   cells is pretty sad. Up-side is that you can readily

   re-use these cells many times over and their

   acquisition costs are nominal.



  http://tinyurl.com/nklo97k



 

   Your right, lithium-iron AA cells poor value compared

   to other choices . . . unless your design goals

   absolutely demand high rate discharge support

   AND long shelf life.



   Its all in the design goals . . .



 

   Bob . . .

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user9253

Joined: 28 Mar 2008
Posts: 1921
Location: Riley TWP Michigan

Posted: Fri Apr 11, 2014 3:44 am Post subject: Re: EarthX lithium

There was a recent comparison of a LiFePo battery versus Lead Acid and the test results posted in a graph on VansAirforce.

http://www.vansairforce.com/community/showthread.php?t=111788

It seems that the actual Amp Hour rating of the LiFePo is only half of the advertised rating.  Even so, a 36 amp hour LiFePo provides almost the same endurance as a PC680 at less than half of the weight.  The author intends to install the LiFePo in his RV-8A.  It will be interesting to see if he is satisfied with this battery a few years from now.

Joe

_________________
Joe Gores

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Apr 11, 2014 5:31 am Post subject: EarthX lithium

At 06:45 AM 4/11/2014, you wrote:

 	  Quote: 	
		  



There was a recent comparison of a LiFePo battery versus Lead Acid 

and the test results posted in a graph on VansAirforce.

http://www.vansairforce.com/community/showthread.php?t=111788

It seems that the actual Amp Hour rating of the LiFePo is only half 

of the advertised rating.  Even so, a 36 amp hour LiFePo provides 

almost the same endurance as a PC680 at less than half of the 

weight.  The author intends to install the LiFePo in his RV-8A.  It 

will be interesting to see if he is satisfied with this battery a 

few years from now.


	


   I missed getting the 4th slot filled on time in

   the series of articles on batteries for Kitplanes.

   Spent an extra month attempting to engage a number

   of suppliers/manufacturers in technical conversations

   about their products.



   Only one has been eagerly forthcoming (EarthX) and

   one other begrudgingly offered tid-bits of the

   requested data.



   I've offered to work with EarthX to wordsmith

   specification and sales literature that would

   get them more than a casual glance and fewer

   snickers from a TC airframer.



   Part IV of the battery articles has been submitted

   to Paul Dye. I've discovered a lot about the current

   state of LiPo offerings but my inquiries have generated

   more questions than answers!



   As the thread cited above demonstrates, there's

   a good bit yet to be learned about the lithium

   battery industry. Encourage folks on the

   VansAirForce-list to join us here on the AeroElectric-

   List as well.



   By the way, that PbEq (lead-acid equivalency) thingy

   is pure marketing hype. It speaks to battery impedance

   and ability to crank engines . . . says NOTHING about

   energy available for battery-only ops.





   Bob . . .

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