ArmyTek
Page 1 of 2 12 LastLast
Results 1 to 30 of 60

Thread: GTL 18650 Battery Test [ Updated ]

  1. #1
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default GTL 18650 Battery Test [ Updated ]

    GTL 18650 Test



    Well , some of you may have noticed the GTL 18650 have hit Ebay . Some may not ! Anyhow , for a while now I have wanted to test them to see just how they perform .

    Anyways , these are not protected , and in single cell use , thats just fine with me .

    Dimensions .
    Lenth = 65.8mm
    Dia = 18mm

    Discharge Capability :

    SSC P7 MTE = 2.9A for the first one and 2.96A for the second one
    More unprotected battery results soon .
    Generic 18650 = 3A
    GTL [ 2nd Try ] = 3A and 3.08A
    Ultrafire Green = 2.8A
    Trustfire = 2.78A
    And just for the heck of it , a freshly charged IMR 18650 = 3.3A
    All batteries were tested freshly of the charger .


    Next Solarforce L2 R2 = 1.6A and 1.62A for the GTL
    Ulatrafire Green = 1.58A
    Generic 18650 = 1.57A
    Trustfire = 1.57A

    Ive just started testing so more to come .
    I will do a runtime test tomorrow .



    GTL is in yellow .. Graph was from my Xtar test , I just added the GTL result .

    Wow , as can be seen , the batteries really pump for 25 minutes and then fall flat on there face , as they would say on Mythbusters , BUSTED !!! No way 2800mAh !!
    You would be lucky to get 1600mAh , Nice output for a little while ...
    Possibly re-badged/labeled 1400 to 1600 capacity batteries / the word Fraud comes to mind , shonky , and a few other choice words come to mind . WORD ! you been told !
    Some one had to be the bunny , and I took a bullet for CPF members .
    Some one in HK is chewing on my ass after taking a bite out of it !
    Last edited by old4570; 01-04-2010 at 07:49 PM.

  2. #2
    Flashaholic
    Join Date
    Nov 2009
    Location
    Slovenia
    Posts
    234

    Default Re: GTL 18650 Battery Test

    You have anything that can measure its capacity properly? The 18650 usually are properly market, lets see whats up with this one

  3. #3
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test

    Quote Originally Posted by T0RN4D0 View Post
    You have anything that can measure its capacity properly? The 18650 usually are properly market, lets see whats up with this one
    No Hobby Charger Here !
    I do a run test .

  4. #4

    Default Re: GTL 18650 Battery Test

    I have never heard of that brand before....is there more info that you can post for people like me that are not familiar with GTL.

  5. #5
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test

    Quote Originally Posted by alfreddajero View Post
    I have never heard of that brand before....is there more info that you can post for people like me that are not familiar with GTL.
    There sold on ebay , at the very top of the page is a link .

    or just search GTL 18650 on ebay etc .

    About to start the run time test .

  6. #6
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Spend your money somewhere else !


  7. #7

    Default Re: GTL 18650 Battery Test [ Updated ]

    Thanks for letting us know how it went.....and thanks for taking one for us, at least we know to stay away from that brand.

  8. #8
    *Flashaholic* kramer5150's Avatar
    Join Date
    Sep 2005
    Location
    Palo Alto, CA
    Posts
    6,328

    Default Re: GTL 18650 Battery Test [ Updated ]

    Informative as always. Thanks for taking one for the team!!
    CLICK HERE for my flashlight reviews.
    PAUL KIM... AN INDUSTRY GENIUS

  9. #9
    Flashaholic* Black Rose's Avatar
    Join Date
    Mar 2008
    Location
    Ottawa, ON, Canada
    Posts
    4,622

    Default Re: GTL 18650 Battery Test [ Updated ]

    Quote Originally Posted by old4570 View Post
    Some one had to be the bunny , and I took a bullet for CPF members .
    Some one in HK is chewing on my ass after taking a bite out of it !
    I hope you waited until after you did your tests to leave feedback.

  10. #10
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Yeah !

    These must be the worst of the worst when it comes to capacity , why on earth would they claim 2800mAh when they would be struggling for 1600mAh , and why put a nice label on rubbish , bit like dressing up a turd and passing it of as chocolate . [ I guess that would be the point ]
    Last edited by old4570; 01-04-2010 at 09:54 PM.

  11. #11
    HKJ's Avatar
    Join Date
    Mar 2008
    Location
    Copenhagen, Denmark
    Posts
    6,487

    Default Re: GTL 18650 Battery Test

    Quote Originally Posted by T0RN4D0 View Post
    The 18650 usually are properly market, lets see whats up with this one
    Not really, the ones I have measured are mostly optimistic with their specifications.
    My website with flashlight, battery and charger information: lygte-info.
    More than 200 battery reviews and 80 charger reviews.
    Compare 18650 LiIon batteries or smaller (RCR123, 16340, 14500, 10450) LiIon batteries.

  12. #12
    Flashaholic
    Join Date
    Nov 2009
    Location
    Slovenia
    Posts
    234

    Default Re: GTL 18650 Battery Test [ Updated ]

    Well sure there is a lot of crap, but DX for example marks them as crap. While smaller ones (16340, AAA and alike) are typically all crap.

    It would be interesting to try it at a lower discharge. Anyone knows the officiall standards for determinating the capacity of these things?

  13. #13
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Quote Originally Posted by T0RN4D0 View Post
    Well sure there is a lot of crap, but DX for example marks them as crap. While smaller ones (16340, AAA and alike) are typically all crap.

    It would be interesting to try it at a lower discharge. Anyone knows the officiall standards for determinating the capacity of these things?
    Wow , thats a very broad brush your using there .

    Lower discharge wont help , they just dont have the capacity to compete with a half decent battery . For the same money you can buy , Trustfire - Ultrafire - or Uniquefire [ New to DX ]

    + A hobby charger that charges and discharges and then calculates capacity .

    If anyone wants to send me one ?????
    ill give it a serious workout .

  14. #14
    HKJ's Avatar
    Join Date
    Mar 2008
    Location
    Copenhagen, Denmark
    Posts
    6,487

    Default Re: GTL 18650 Battery Test [ Updated ]

    I am working on a test of 18650 batteries, using a CBA battery analyzer.
    Here are some preliminary results:
    AW2200: 2100mAh
    Trustfire2500: 2150mAh
    UltraFire2600: 2200mAh
    Xtar2200: 2250mAh

    The capacity will vary depending on discharge current, but not more than 100-200mAh from 0.3A to 3A current
    My website with flashlight, battery and charger information: lygte-info.
    More than 200 battery reviews and 80 charger reviews.
    Compare 18650 LiIon batteries or smaller (RCR123, 16340, 14500, 10450) LiIon batteries.

  15. #15
    Flashaholic
    Join Date
    Aug 2009
    Location
    london
    Posts
    225

    Default Re: GTL 18650 Battery Test [ Updated ]

    Well done old4570, I to was going to purchase GTL16340 1200mAh batteries but everyone advised me not to buy them.

    I was still wanted to know if the capacity was correct. With you testing the 18650 model and proving that they are only half the capacity, the 1200mAh must be 400mAh.

    Thanks for biting the bullet .

  16. #16
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Quote Originally Posted by how2 View Post
    Well done old4570, I to was going to purchase GTL16340 1200mAh batteries but everyone advised me not to buy them.

    I was still wanted to know if the capacity was correct. With you testing the 18650 model and proving that they are only half the capacity, the 1200mAh must be 400mAh.

    Thanks for biting the bullet .
    The only CR123A with 1200mAh might be some high quality Primaries [ Non rechargeable ] , which is why some folk like there primaries .

    Rechargeable CR123A,s might come close to 650mAh or possibly more , but usually think in the neighborhood of 500-600mAh , again very dependent on the individual cell and quality . I have a few that have topped 600mAh capacity .

    Flea Bay batt pushed some : 676mA to the 30 minute mark .
    Spiderfire Pushed some : 619mA to the 30 minute mark .
    AW did some : 620mA Give or take at the end , depending on just when it became depleted .
    KD = some 545mA
    Solarforce = 544mA





    Trustfire = 513mA
    DX = 342mA
    Ultrafire No 8 = 528mA
    Ultrafire no 7 = 590mA
    Ultrafire Flea Bay No 5 = 535mA

    Unfortunately I no longer have the images from that test so cant re-fresh the post .

    1/ KD – PRCR123A 3.7v - 625mAh - $3.01 each
    2/ Solarforce PRCR123A 3.7v – 880mAh - $3.95 each [ 800mAh claimed by seller ]
    3/ Trustfire – PRCR123A 3.7v – 880mAh - $2.25 each .
    4/ E-bay – RCR123A 3.7v – 1000mAh - $2.20 each.
    5/ Ultrafire – RCR123A 3.7v – 880mAh - $3 each [ Ebay ]
    6/ AW- PRCR123A 3.7v – 750mAh - $9 each
    7/ Ultrafire – PRCR123A 3.7v – 1000mAh - $3.19 each
    8/ Ultrafire – PRCR123A 3.7v – 880mAh - $2.50 each
    9/ DX - RCR123A – 800mAh 3.7v - $1.64 each .
    10/ Spiderfire – PRCR123A 3.7v – 1000mAh - $4 each

  17. #17
    Flashaholic
    Join Date
    Dec 2001
    Location
    Silicon Valley CA
    Posts
    241

    Default Re: GTL 18650 Battery Test [ Updated ]

    Too bad you can't somehow link this review to the seller's Feedback on ebay... thanks for testing those cells, very small sample size but obviously 2800 is a HUGE LIE !!!

  18. #18
    Flashaholic* Larbo's Avatar
    Join Date
    Aug 2009
    Location
    NJ
    Posts
    541

    Default Re: GTL 18650 Battery Test [ Updated ]

    Careful those things dont go

  19. #19
    Flashaholic
    Join Date
    Aug 2009
    Location
    london
    Posts
    225

    Default Re: GTL 18650 Battery Test [ Updated ]

    old4570 are you going to test the Following?

    2 x Superfire RW 18650 2600 mAh 3.7V Protected Battery(orange)

    4 x RECHARGE 18650 2800mAh Superfire 6P 12P BATTERY(Blue)

    4 x Superfire 18650 Li-ion 2600mah Rechargeable Battery(Green)

    Just saw these on flea bay.

  20. #20
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Quote Originally Posted by how2 View Post
    old4570 are you going to test the Following?

    2 x Superfire RW 18650 2600 mAh 3.7V Protected Battery(orange)

    4 x RECHARGE 18650 2800mAh Superfire 6P 12P BATTERY(Blue)

    4 x Superfire 18650 Li-ion 2600mah Rechargeable Battery(Green)

    Just saw these on flea bay.
    I was looking at the superfire batteries ... When I buy some ?
    It was a choice between the GTL and Superfire , I thought the GTL would be the worse of the two .

    Maybe in a couple of weeks .

  21. #21

    Default Re: GTL 18650 Battery Test [ Updated ]

    capacity you got from you GTL 2800mah ?

    1100mah at 1A down to 3V, 4.11V start voltage
    1647mah at 0.5A down to 3V

    doing a new test, ultrafire charger,... cell shows 4.22V
    while my hyperion charger , does 4.11V ??

    still like to find out what's the max you ever got out of them ?

    did not cycle them, any tips how to cycle them ?
    how to break them in?
    how many cycles, charge 1A , discharge maybe to 3.4 , do it maybe 3x ?
    and how does the rest time work? think it's bad to discharge right after full blast charge ?

  22. #22
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Actual capacity , probably around 1400mA [ Not very flash ]
    Max ? Run time ? Havent measured that after the test .

    Cycling ? Li-ions should not need cycling , nicads yes .

    Lion - break in - Some folks cycle there Li-ions @ 500mA on a hobby charger to try and condition the battery for best capacity ... [ Gentle ]

    I give my batteries about 1 hours rest after charging ...
    Is it bad to use them right after charging ? I dont think so ?

    Li-ion have a use life of about 5 years , and whether U use them or not they will degrade , they degrade slower in the fridge and if you wish to store them then about 80% capacity is better . But after 5 years there some what stuffed ... Did I hear 10% loss per year ... I would expect this to be also very dependent on each individual cell .

    I still use a GTL in a L2 XP-G R5 .. Though I dont expect a great deal of runtime as it sux up to 1.8A @ the tail .

    For the price , the GTL are disappointing , you can buy Ultrafire or Trustfire for that price and have a much better cell , and they will maintain higher capacity for 5 years .

    The only thing I liked about the GTL is its low internal resistance and high discharge rate .. Otherwise there are much better batteries to chose from for the same price .

  23. #23

    Default Re: GTL 18650 Battery Test [ Updated ]

    i did 2 of mine today (gtl's) 1100 from 4.2 to 3.0 at 1a.

    charging them now to do it at .5a

  24. #24
    Unenlightened
    Join Date
    Mar 2010
    Posts
    1

    Default Re: GTL 18650 Battery Test [ Updated ]

    Hello everybody,

    I have a question about the first charge of li-ion batteries. I have a metal detector that has a battery pack consisting of eight 3.7 V li-ion batteries, with 2000 mAh. Recently couple of the batteries died so i decided to change all of them with the GTL batteries. The charger that comes with the battery pack has some kind of inteligent charging, which charges the batteries in periodic times. I am guessing it has something with the temperature of the batteries. After 3-4 hours the charger shut downs and a led diode indicator signals that the battery pack is fully charged and it is ready to use. Do you think that with this way of charging i cannot succeed the maximum capacity of all of the batteries? I am guessing that the original batteries were fully charged on some other device in the factory, before they were implemented in the battery pack. I see this as a way that you cannot change the batteries yourself. Tell me what do you think? Have any of you guys encountered the same problem?
    Sorry for my bad english. This is my first post.

  25. #25
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Quote Originally Posted by Bakimir View Post
    Hello everybody,

    I have a question about the first charge of li-ion batteries. I have a metal detector that has a battery pack consisting of eight 3.7 V li-ion batteries, with 2000 mAh. Recently couple of the batteries died so i decided to change all of them with the GTL batteries. The charger that comes with the battery pack has some kind of inteligent charging, which charges the batteries in periodic times. I am guessing it has something with the temperature of the batteries. After 3-4 hours the charger shut downs and a led diode indicator signals that the battery pack is fully charged and it is ready to use. Do you think that with this way of charging i cannot succeed the maximum capacity of all of the batteries? I am guessing that the original batteries were fully charged on some other device in the factory, before they were implemented in the battery pack. I see this as a way that you cannot change the batteries yourself. Tell me what do you think? Have any of you guys encountered the same problem?
    Sorry for my bad english. This is my first post.
    I would open up the detector , and with a Multi Meter measure the voltage of each cell , if there even , you have little to worry about .

    If there not even , then you may need to individually charge the cells .

  26. #26
    Unenlightened
    Join Date
    Jul 2010
    Posts
    1

    Default Re: GTL 18650 Battery Test [ Updated ]

    My initial tests on the GTL li-ion give about 800 mAhrs NOT 2800!! I did notice that i can discharge to zero and then recharge.. I wonder if these are really li-ion cells or three nicads in the same can?? !!

  27. #27
    Enlightened
    Join Date
    Sep 2010
    Location
    Switzerland
    Posts
    55

    Default Re: GTL 18650 Battery Test [ Updated ]

    Quote Originally Posted by themotorman View Post
    My initial tests on the GTL li-ion give about 800 mAhrs NOT 2800!! I did notice that i can discharge to zero and then recharge.. I wonder if these are really li-ion cells or three nicads in the same can?? !!
    Hi all !
    I'am new here (as a writer ) and I have found this topic by searches on the web about GTL batteries.

    I bought 6 of these cells to repack a laptop battery. But in my first tests, after about 2-3 charges, a cell has died (~0.25V).
    In addition, the capacity of the repacked battery was very bad, badder than with orignal cells and recuperated cells from other pack.

    I have open a cell to see what is exactly inside (with a lot of care, of
    course) and :










    This is li-ion.
    The surprise was when measuring the voltage on the circle (positive) on the second photo : it is >4.00V ! What has happend to the cell ? When closed, 0.25V on the top.. with cap removed 4V ! (but I have not tried to load the cell).

    Final words : cheap and very bad cells. never buy this again.

    If someone has link to homebuild charger/discharger to measure the capacity, I am interested !

    (sorry for my poor english...)

  28. #28
    Flashaholic* old4570's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne - Australia
    Posts
    2,575

    Default Re: GTL 18650 Battery Test [ Updated ]

    Get a hobby charger !

    Set it to cycle , charge + discharge , and it should report the capacity for each cycle ...
    Nice pictures + PS , TOXIC ! POISON ! , I hope you took appropriate precautions ...
    Last edited by old4570; 09-03-2010 at 06:35 PM.

  29. #29
    Enlightened
    Join Date
    Sep 2010
    Location
    Switzerland
    Posts
    55

    Default Re: GTL 18650 Battery Test [ Updated ]

    Something like this :

    http://www.all-battery.com/tenergyb-...ger90252.aspx#

    Do you have ref (model or a post in this forum) about hobby chargers ?

    Thank you. Yes, all was done in free air, with security glasses, gloves. All was fine, only a small heating of the cell.

    Some one has an idea of what happend to this cell ? "Inside" was functionning, but bad contact with the top cap ? Is there an expert

  30. #30
    Flashaholic* Ray_of_Light's Avatar
    Join Date
    May 2003
    Location
    West Midlands, U.K.
    Posts
    1,144

    Default Re: GTL 18650 Battery Test [ Updated ]

    They look like the typical high-current, low-capacity batteries made for tools.
    At this point I am inclined to believe that the GTLs ARE tool batteries re-packaged and re-labeled to appear as consumer' 18650s.

    Anthony
    VENI, COLLUXI, VICI.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •