Results 1 to 8 of 8
  1. #1
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,050

    VXl-3s 7.4v LiPo possible problems

    I know when my grandson calls or texts me it means he has accomplished something either very cool with his Slash or he broke something

    I can fix broken things I told him easily but I can't fix what I can't figure out in electronics so I ask for help/suggestions and if this is in the wrong forum please move it.

    VXL-3s with Velineon motor. Venom 2s 8.4v Lipo's. His charger is a Dynamite model mine is a new Traxxas EZ Peak Plus. He had one battery that would not take a charge so I told him to bring me both his batteries. Battery #1 showed a cell at 1.49v other I think at 3.46 or so. Would not charge for me either. Moved on to Battery #2 and fully charged it on Balance Lipo setting and off he went. Yes Green Light on VXL for low voltage protection was active and he ran the battery. Now he calls me to say it won't go in charge mode on his charger?

    So, is it just dumb luck that two used batteries have gone bad or is it more likely the ESC is allowing the batteries to discharge too far before cut off?? Would cold weather 27ish have any effect on it? I don't want to buy new batteries to find out the ESC is going to harm them. At what point will the charger not detect or begins to charge a cell??

  2. #2
    RC Turnbuckle Jr.
    Join Date
    Oct 2009
    Location
    Springfield, MO
    Posts
    3,680
    Can you rig a set of pins to plug into the balance taps? You can try charging each cell individually, and see if they take equal mah, or if one never really charges...

    Did you say you bought these batteries used? If so cut your loses and pick up your own packs.


    Edit:

    Also a cell monitor... you can check each cell's voltage periodically while you run.

  3. #3
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,050
    Think I am on to the problem now. I just picked up the wounded battery and see the balance leads are broken. They have been fixed and the battery is charging properly. I will look more closely at the other battery for possible same problem but it has the weak cell so it is likely doomed.
    Yep, need to get more batteries!!

  4. #4
    RC Turnbuckle Jr.
    Join Date
    Dec 2004
    Posts
    3,762
    Quote Originally Posted by kwitty View Post
    Think I am on to the problem now. I just picked up the wounded battery and see the balance leads are broken.
    Yeah, balance leads are thin and can be very fragile. Tugging or pulling on them is a guaranteed break waiting to happen.

  5. #5
    RC Qualifier
    Join Date
    Jul 2010
    Location
    Salem, OR
    Posts
    416
    we learned lipo batts are plain finicky and just require more attention to detail. Its hard for little kids to get right though. I am experiencing same issues with my nephews. They are too young to be super attentitive which has lead to some popped batteries. All but one runs nimh now... lipo charging bags are good for young users to have imo too if not all users
    'Life is for living, not living uptight'

  6. #6
    RC Turnbuckle Jr.
    Join Date
    Oct 2009
    Location
    Springfield, MO
    Posts
    3,680
    Its true they take a little more attention... but nimh's are just as scary to me.

  7. #7
    RC Champion
    Join Date
    Aug 2011
    Location
    El Cajon Ca
    Posts
    1,805
    I personally only allow my younger grand children, 5-9 years, to use nimh for safety reasons and I charge the batts but they remove and replace the batterys and have instructed them to pull or push only on the connectors not the wires. Has saved me alot of grief..... NOW the bashing is a little different....I have little control there So some spare parts are needed
    "enjoy your ride"

    Dennis

  8. #8
    RC Champion
    Join Date
    Nov 2011
    Location
    North Central OH
    Posts
    1,050
    Jakey wrote Yeah, balance leads are thin and can be very fragile. Tugging or pulling on them is a guaranteed break waiting to happen
    You are correct, not much area to grab on to to pull at the plug itself on the balance connector, likely to be an issue again. I always wanted to take apart a LiPo LOL

    I personally only allow my younger grand children, 5-9 years, to use nimh for safety reasons and I charge the batts but they remove and replace the batterys and have instructed them to pull or push only on the connectors not the wires. Has saved me alot of grief..... NOW the bashing is a little different....I have little control there So some spare parts are needed
    Gonna stick with the LiPo packs for him at 12yrs old, his charger is LiPo only and it is Red light on charger is OK and Green light on VXl-3s OK to run! Unfortunately I am not available enough to charge him up but he is a quick learner and a smart kid so I feel we are safe and he can text me anytime he is uncertain and he does. He now knows that what he breaks he will learn to fix..............at my expense of course LOL and that is OK with me
    Last edited by cooleocool; 01-03-2012 at 11:15 PM. Reason: post merge

Posting Permissions

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