Results 1 to 24 of 24
  1. #1
    RC Racer
    Join Date
    Jul 2007
    Posts
    146

    2x 2S1P 1800mah Tenergy Lipos?

    Has anyone tried the Tenergy 1800mah 2s Lipos made for the 1/16 scale stuff?
    Shown here

    I ordered a set and they should be here tomorrow but thought I would ask around. Heck for the set they were only $35 to my door. I will run them on my truck, on the CBA, and get back with the results. Hopefully they don't turn into big balloons

  2. #2
    RC Turnbuckle Jr.
    Join Date
    Jun 2010
    Location
    Miami, Fl
    Posts
    6,731
    I had some tenergy Nimh pack for my rustler and they were awesome, I beleive those will perform good, but havenīt tried their lipo.

  3. #3
    RC Racer
    Join Date
    Dec 2010
    Location
    SJ Cali
    Posts
    115
    I was running 2s for a bit in my truck, im running the ********* 2s 1800 and they work great. More power than the nimh and better run time. Then I got some ********* 3s 1500 packs and man this thing rips with them! Now I just run 3s.

  4. #4
    RC Racer
    Join Date
    Nov 2010
    Posts
    180
    Let us know how they work. Looks like a great deal. Local shop wants $60 for a pair from another brand.

  5. #5
    RC Qualifier
    Join Date
    May 2010
    Posts
    659
    let me know what kind of run time you get?

  6. #6
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    Will do guys, I'll give a full report once I get them in, I'll just post it in this thread. You can't beat that price, I was originally going to get the maxamps setup but it was going to cost me around $95 to my door for the same series and mah setup. Hopefully I won't be disappointed. If your going to order them before my mini review be sure to use the coupon code to save 12% more, I think it expires on 1/3/2011:

    HOLIDAY12

    A bummer note, it turns out the company is only 40 minutes from my house and they will let you do pickup to save on shipping. Of course I did not know this upon placing my order, which was estimated to arrive today. I just checked the tracking info for fedex home delivery and is still estimating a delivery of today but doesn't show that the item was even picked up, instead just the electronic information was received, my guess is it will be here tomorrow

  7. #7
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    I finally got my packs today.




    Initial external impression:

    The packs seem well built and are your classic soft pack made of a glass tape and a piece of shrink wrap. The wiring is 16ga for the high power wire and is made of 200c silicon. They are quite flexible and seem softer than the stock traxxas nicad pack wiring. The balance leads are JST connectors and also use a soft quality silicon wire. The traxxas HC connectors look to be authentic.



    They seem to easily fit in my new summit 1/16th vxl with no issue what so ever. The wires are thin enough to perfectly fit in the stock door with no modificiation.



    Initial charging:

    I'm a bad reviewer and forgot to measure my packs in their arrival voltage. Pack A2 as it was charged showed that it was quite out of balancing. After about 500mah going in the one cell started limiting my charge holding a voltage of 4.10v while the other was at 3.90v. It took a long time from here since it was so out of balance. Pack A1 was much better and took only about 400 mah and maintained balance through the cycle. Pack A1 gave me a bit of cause for concern but I will see if it will affect the pack in the discharges later.






    Battery tests:

    Well of course these pack go here pretty late in the day and with a dentist appointment I didnít get to test the packs on the truck yet. But I did run them on the CBA unit. The packs were only charged to 4.10v instead of 4.20 just to add a bit of longevity to the pack. They were discharged at rate of 10 amps and 3.6 amps. 10 amps is equivalent to draining the two packs in the car in just over 5 minutes (20a total), and 3.6a is a half an hour in the car (7.2a total). Individual packs were tested as shown:


    The packs heated a decent amount at the continuous 10a going from 69F to about 113F. The 3.6a packs heated from about 69F to 90F. I think 20C continuous might get this packs pretty hot. But realistically the truck will take 30 minutes or more to discharge these packs, which really is just 2C.
    They put out between 1.51ah to 1.57ah and since I am not going to 4.2v I am pretty happy with that. Enough of these crazy deep cycles I canít wait to get it in the dirt tomorrow morning.

    I will give one last update to the real world performance and run time.


    Ok final update:

    So today I got to run the packs on my 1/16 summit VXL and it really is a blast. The power is quite unreal and top speed is plenty for me. I didn't think there would be as much top end difference but I was quite wrong, it really hauls!

    That being said run time leaves a bit to be desired. I am getting about 23 minutes of running with these lipo packs when charged to 4.15v per cell. The truck is definitely being run harder as I measured the motor holding at about 150F from a starting temp of 68F and ambient 47F. The controller never measured over 95F.

    All and all I'm happy with the purchase for the price but would still strive to get longer run times in the end.

    So the reason it goes much faster is apparent when you compare the 10a cycle to the traxxas NIMH pack:

    Last edited by cooleocool; 01-01-2011 at 09:07 AM. Reason: merge

  8. #8
    RC Qualifier
    Join Date
    May 2010
    Posts
    659
    so how long does it take to charge each pack?

  9. #9
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    Just barely over 1 hour at 1.8 amps charger rate. The packs have a specs written on them that okays them for 2c charge rate of 3.6 amps which should bring them down to 30 minutes.

    Thanks coolecool for the merge.

  10. #10
    RC Turnbuckle Jr.
    Join Date
    Nov 2006
    Location
    USA
    Posts
    3,038
    The reason your not getting longer runs is your not charging the packs all the way... they will take more Mah to fill them to the 4.2v per cell
    If you charge these packs at 1.8amps they will take less than an hour to charge
    1hr = 1800mah
    First MiniSlash
    HK6XL Revo 4s 60mph Amsoil dealer

  11. #11
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    Quote Originally Posted by filmmaker View Post
    The reason your not getting longer runs is your not charging the packs all the way... they will take more Mah to fill them to the 4.2v per cell
    If you charge these packs at 1.8amps they will take less than an hour to charge
    1hr = 1800mah
    You are correct and I should have addressed that. A 4.1v charge will give you about 85% of the rated capacity, 4.15 about 92%. The reason to do this is to allow for long cycle life. Lithium polymer has a fairly high self degration rate that increases with higher voltage. You can actually squeeze a lot more capacity out of a lipo cell by over charging them (very dangerous) but you will get very very crappy cycle life. From what I read using a 4.1v charge and good discharge shut off you can pull off double the cycles.

    The reason it takes long than an hour to charge an 1800mah pack at 1800mah is the constant voltage part of the cycle. Lithium cells are charged using constant current then constant voltage (CC/CV). The pack is first charged at a constant current to a given voltage, then that voltage is held as the current is reduced to a set termination amperage. The pack will reach about 80% on the CC stage and take an easily calculated time but the CV stage take much longer to do that last 20% since the current is being reduced.

    I will charge the packs up to 4.2 per cell and do one more graph to see what we come up with.
    Last edited by maudaman; 01-02-2011 at 01:22 AM.

  12. #12
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    With a 4.2v per cell charge at around 68F ambient, 5.4 amp discharge to 6.3v ended with 1722 mah. Addition lower cutoff voltage and 1C discharge would probably put it at 1800mah.


  13. #13
    RC Turnbuckle Jr.
    Join Date
    Nov 2006
    Location
    USA
    Posts
    3,038
    Quote Originally Posted by maudaman View Post
    You are correct and I should have addressed that. A 4.1v charge will give you about 85% of the rated capacity, 4.15 about 92%. The reason to do this is to allow for long cycle life. Lithium polymer has a fairly high self degration rate that increases with higher voltage. You can actually squeeze a lot more capacity out of a lipo cell by over charging them (very dangerous) but you will get very very crappy cycle life. From what I read using a 4.1v charge and good discharge shut off you can pull off double the cycles.

    The reason it takes long than an hour to charge an 1800mah pack at 1800mah is the constant voltage part of the cycle. Lithium cells are charged using constant current then constant voltage (CC/CV). The pack is first charged at a constant current to a given voltage, then that voltage is held as the current is reduced to a set termination amperage. The pack will reach about 80% on the CC stage and take an easily calculated time but the CV stage take much longer to do that last 20% since the current is being reduced.

    I will charge the packs up to 4.2 per cell and do one more graph to see what we come up with.
    No one ever said to over charge a lipo
    that is a very dangerous thing to do, not only will the battery fail, but you can burn down your house or whatever your charging in
    charing the packs to 100% will not shorten the life span of the pack, but taking 100% out of the pack will!
    one should only take 80% out of any lipo pack to take advantage of longer life cycles, not undercharging them
    undercharging them and taking out 100% will shorten the life of the pack
    Last edited by filmmaker; 01-02-2011 at 09:52 AM.
    First MiniSlash
    HK6XL Revo 4s 60mph Amsoil dealer

  14. #14
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    Quote Originally Posted by filmmaker View Post
    No one ever said to over charge a lipo
    that is a very dangerous thing to do, not only will the battery fail, but you can burn down your house or whatever your charging in
    charing the packs to 100% will not shorten the life span of the pack, but taking 100% out of the pack will!
    one should only take 80% out of any lipo pack to take advantage of longer life cycles, not undercharging them
    undercharging them and taking out 100% will shorten the life of the pack
    I was merely saying that it is possible (again Dangerous) to over charge at the sacrifice of life cycles. I was not saying charging to 4.2v was over charging but it will not provide as many cycles as a lower terminal voltage. It is a fairly well researched aspect of lithium based chemistry:

    This is what I was talking about when overcharging (DO NOT ATTEMPT VERY DANGEROUS)

    You can read about lower charging terminal voltage here:

    Quote Originally Posted by everydayflier from RCgroups
    Years ago it was determined that charging LiPolys to only 4.1 volt per cell instead of 4.2 greatly increase the number of cycles they would deliver all other things being equal. Many LiPoly chargers have such an option and many of the very old ones have a LiIon setting which is also 4.1 per cell . Also as mentioned limiting depth of discharge and proper storage goes a long way toward increasing their useful life.


    From my TP 1010C / 210V Thread 5 years ago

    http://www.rcgroups.com/forums/showp...&postcount=25c

    Quote:
    The 95% charge(at 1C) would charge to 4.15V to 4.16V depending on battery condition (I will do more test to comfirm these data)

    I recommend Fast charge setting for normal use, Full charge 100% setting for competition and demo use.

    Regards,
    Charlie

    FMA and Kokam conducted extensive LiPoy testing years ago and found that LuPoly life was greatly increased by chatrging to a max of 4.1 per cell. FMA LiPoly chargers have had this option for years and on the Cell Pro 10 and POWERLAB 8 it is listed as Long(er) Life.
    Quote Originally Posted by http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

    Generally speaking, batteries live longer if treated in a gentle manner. High charge voltages, excessive charge rate and extreme load conditions will have a negative effect and shorten the battery life. This also applies to high current rate lithium-ion batteries.
    This is also a good read:

    http://powerelectronics.com/portable...ttery-life.pdf



    Shallower depth of discharge will help as you have said, but so does lower terminal voltage. I find it easier to use a lower charge voltage since my cuttoff is not programmable on the truck. This will result in longer life on these cells in contrast to charging them to 4.2v with the same cutoff device

  15. #15
    RC Racer
    Join Date
    Nov 2010
    Posts
    180
    As Bones would say, "D#$% it Jim! I'm a doctor not an engineer!"

    To be honest, I don't fully understand all those charts. But I assume they mean these batteries have a decent discharge rate, as well as the way the are charged effects performance and runtime.

    My question is; how do these $35 batteries compare to say more expensive "brand-name" LiPo's?

  16. #16
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    Quote Originally Posted by Ranzou View Post
    As Bones would say, "D#$% it Jim! I'm a doctor not an engineer!"

    To be honest, I don't fully understand all those charts. But I assume they mean these batteries have a decent discharge rate, as well as the way the are charged effects performance and runtime.

    My question is; how do these $35 batteries compare to say more expensive "brand-name" LiPo's?
    Well they put out their rated capacity and seem to handle the vxl with no warming while on the truck. I unfortunately don't own any expensive counterparts to test against.

  17. #17
    RC Turnbuckle Jr.
    Join Date
    Nov 2006
    Location
    USA
    Posts
    3,038
    Quote Originally Posted by Ranzou View Post

    My question is; how do these $35 batteries compare to say more expensive "brand-name" LiPo's?
    these packs work great, and you do not need to spend big bucks to get great performance out of brushless systems...
    remember when you buy name brand, part of the cost is the name, plus marketing..
    First MiniSlash
    HK6XL Revo 4s 60mph Amsoil dealer

  18. #18
    RC Turnbuckle Jr.
    Join Date
    Nov 2006
    Location
    USA
    Posts
    3,038
    Quote Originally Posted by maudaman View Post
    I was merely saying that it is possible (again Dangerous) to over charge at the sacrifice of life cycles. I was not saying charging to 4.2v was over charging but it will not provide as many cycles as a lower terminal voltage. It is a fairly well researched aspect of lithium based chemistry:





    Shallower depth of discharge will help as you have said, but so does lower terminal voltage. I find it easier to use a lower charge voltage since my cuttoff is not programmable on the truck. []This will result in longer life on these cells in contrast to charging them to 4.2v with the same cutoff device[/]
    by your math erlier you have taken our out more than 100% of you packs capacity and that will shorten the life of the packs faster than most anything else
    1722mah plus 15% more to charge to the full of 4.2v percell = 1992mah in a 1800mah pack
    charging lipos to the safe 4.2v per cell does not shorten the life span of the pack..
    every charger on the maket for lipos charges them to 4.2v per cell, and that is not over charging the packs...
    First MiniSlash
    HK6XL Revo 4s 60mph Amsoil dealer

  19. #19
    RC Racer
    Join Date
    Jul 2007
    Posts
    146
    Quote Originally Posted by filmmaker View Post
    by your math erlier you have taken our out more than 100% of you packs capacity and that will shorten the life of the packs faster than most anything else
    1722mah plus 15% more to charge to the full of 4.2v percell = 1992mah in a 1800mah pack
    charging lipos to the safe 4.2v per cell does not shorten the life span of the pack..
    every charger on the maket for lipos charges them to 4.2v per cell, and that is not over charging the packs...
    Well no earlier numbers specify how much capacity went into the pack. I am using proper cuttoff in the tests ie not discharging the cells below 3.15 so I was not damaging the cells ; the test which achieved 1722 was charged at the full 4.2v per cell 1.8a with a cutoff current of 100ma with a cutoff of 3.15v per cell.

    charging lipos to the safe 4.2v per cell does not shorten the life span of the pack..
    Yes it will. If contrasted to charging the pack to 4.10v and all other conditions being the same you will have half as many cycles.
    4.2v is considered the best compromise point in the charge to get around 300 cycles and decent capacity. If you charge to 4.1v you will get 600 cycles but with lower capacity output.

    4.2v charging will not lower shorten the life span of the pack when compared with charging the pack to 4.2v, yes that is correct. *

    Your getting stuck up on wording how bout we say charging to anything below 4.2v per cell will extend the life of your lipo batteries.

  20. #20
    RC Racer
    Join Date
    Dec 2009
    Posts
    149
    Quote Originally Posted by maudaman View Post
    how bout we say charging to anything below 4.2v per cell will extend the life of your lipo batteries.
    I'd love to hear Jakey's input on this.

  21. #21
    RC Turnbuckle Jr.
    Join Date
    Dec 2004
    Posts
    3,652
    If a person wants to deliberately undercharge a pack to help prolong pack life, so be it, however I would rather enjoy the ultimate performance that can only be had from a fully charged pack as opposed to more potential cycles.

  22. #22
    RC Turnbuckle Jr.
    Join Date
    Nov 2006
    Location
    USA
    Posts
    3,038
    Quote Originally Posted by Jakey View Post
    If a person wants to deliberately undercharge a pack to help prolong pack life, so be it, however I would rather enjoy the ultimate performance that can only be had from a fully charged pack as opposed to more potential cycles.
    I agree, specially when most packs get jacked somehow before 300 cycles anyway...
    I never thought about what you said Jakey about not having full potential of a partial charged pack vs fully charged
    one cannot get max performance on a partially charged pack
    First MiniSlash
    HK6XL Revo 4s 60mph Amsoil dealer

  23. #23
    RC Racer
    Join Date
    Nov 2010
    Posts
    180
    My LHS has these batteries in stock - for $31.95 each! Thanks for the deal link Maudaman! I discovered my RC helicopter came with a .8A LiPo balanced charger. So I'm going Lipo.

  24. #24
    RC Qualifier
    Join Date
    Apr 2010
    Location
    Somewhere
    Posts
    991
    Quote Originally Posted by maudaman View Post
    Has anyone tried the Tenergy 1800mah 2s Lipos made for the 1/16 scale stuff?
    Shown here

    I ordered a set and they should be here tomorrow but thought I would ask around. Heck for the set they were only $35 to my door. I will run them on my truck, on the CBA, and get back with the results. Hopefully they don't turn into big balloons
    Hey man thanks for the link I just ordered a set.
    No you cant drive it
    my RC is owner operated only

Tags for this Thread

Posting Permissions

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