Search results

Date Relevance Most replies

  1. S

    14....or 16s balance charger?

    The easiest is to use a voltage alarm on the balance leads. At least on the weakest cell. Balance the cells manually to the planned end voltage (top balance) then monitor them as you drain the pack. Locate the weakest cell and decide upon a depletion voltage you never should exceed when...
  2. S

    2 chargers won't work TaoTao ATE501 scooter

    Measure the output voltage of your charger. I've heard of chargers breaking without obvious signs. What happens is the current cutoff (green light) occurs at a lower voltage than required resulting in a much lower charged battery. The sudden fuel gauge drop could be the result of the voltage...
  3. S

    iCharger 4010 Duo review

    If you have two separate 10s chargers running on separate power sources you can charge the 20s pack without breaking the internal connection. Or four 5s chargers. You get the point. The most convenient thing to do (for a hobby project) is to split the pack and charge on one charger. If you...
  4. S

    Mating a 60v battery to a 52V 750w Tongsheng TSDZ2

    With a fully charged battery you need to stay below the capacitor rating, maybe even with a safety margin. What you can do is to use low voltage sag cells and put more cells in parallel. That way you get less voltage sag when you pull a lot of amps. You could if there is a bms solution...
  5. S

    Zero 2012 XU

    The specs mention a 220amp controller and a 90% sustained max speed (100% burst) which guides me to assume the pack is rated at 200amps continuous. If you have an 18s2p you have 100amps per cell. We don't know the voltage. Perhaps you are running lifepo4 @ 3.65v or Lico/lipo at 4.2v. The specs...
  6. S

    Building a high Amp output battery question

    What about running a higher voltage and fewer amps = equal watts. Good for a high performance (limited range) EV build. Thinner cables, smaller controller components :) What about two wheel drive?
  7. S

    14....or 16s balance charger?

    What's the capacity of your largest cell and how long do you wish for it to charge? Hobby chargers are not safe to leave unattended. An unbalanced pack is unsafe to charge/discharge in series. Use a working voltage alarm perhaps. How about installing a bms but not counting on it to balance...
  8. S

    Balancing a 20s battery back

    By top balancing the pack at 4.2v this should be helped. Also that there are three cells in parallel can help minimize a small imbalance. The original charger assumes the pack to always be balanced at 4.2v which is unwise. By lowering the voltage to 4.10v you have a small safety buffer. You...
  9. S

    Balancing a 20s battery back

    Bulk charging also unbalances a pack if the IR/capacities are off. Bulk charging, using a high voltage dc power brick and charge to 84V. (4.2x20) No it's a 30km/h unicycle. Light one that can be carried up an occasional stair without breaking your back. (Inmotion V8) Yes since I will have the...
  10. S

    Balancing a 20s battery back

    I decided to go with the 3s charger. Seems the new 20w version has a better end voltage. 4.19-4.20v To keep things simple I'll hook up seven 3s leads hanging out of the pack. That way I can't connect the chargers wrong. I'll test the chargers end voltage before trying it on the pack. If I...
  11. S

    Balancing a 20s battery back

    It's an electric unicycle. 800w nominal/2000w peak. Original it comes with a 20s2p battery. I have two unicycles so I can work on the new battery pack as I'm riding the other. I'm going from 40 to 60 cells to increase the range and also because thats the only amount that will fit inside of it...
  12. S

    Balancing a 20s battery back

    I think the ichargers and imax chargers all rely on serial charging to do the bulk of the charging and do only a fraction of the power through the balance leads at a very slow rate, constantly switching between serial charging and bleeding power from the other overcharged cells. This is useless...
  13. S

    Balancing a 20s battery back

    Hey thanks for the info... Do you disconnect the 24s pack's internal serial connection before hooking it up to the battery nanny? Because I have my balance leads in parallel with the stock bms I'm not sure I can disconnect the serial connection or that disconnecting it won't still create...
  14. S

    Balancing a 20s battery back

    Hi lithium enthusiasts... After the new 20s3p 84v lg mh1 pack is finished (and hooked up to the original bms) I will have balancing leads going out from the pack. I've heard that this original bms dosn't really balance the cells. Even if it does it can't handle large imbalances. Anyway I need...
  15. S

    Used 18650, cell matching question. Match by IR or capacity?

    Hi fellow lithium battery enthusiasts :) In a week or two I'll spotweld my "new" 84v unicycle battery together. It's a 20s3p configuration. Current draw is about 3A per cell on avg. Charging rate is around 0.8-1A per cell. I'm building it from used LG MH1 18650 cells of slightly varying...
Back
Top