›
This forum is in permanent archive mode. Our new active community can be found here.

Battery Charging

Victor FrostVictor Frost
edited March 2010 in Technology
Okay, so here's my deal. I've got a "dumb" charger that was meant for a 7.2v 1500mAh NiMh 6 cell battery and I was given two 7.2v 2000mAh NiMh 6 cell batteries.

Please tell me if my logic is correct/incorrect: If the 1500mAh Battery takes 6 hours to charge, then the 2000mAh (having 1/3 more capacity) should be charged for 8 hours.

Comments

  • Dr. TimoDr. Timo
    edited March 2010
    You are correct. Also NiMH's are not too dangerous to overcharge a little bit (it will decrease their life span) unlike LiPO's (which will explode).
    Post edited by Dr. Timo on
  • Victor FrostVictor Frost
    edited March 2010
    Thanks Timo, You just saved me $40. Although, that $40 charger can charge all my nimh batteries and is smart enough to know when to stop charging. -_- Maybe I should buy it after all...

    Alright, I've also got a 4 hour quick charger designed for a 9.6 volt 1800mAh 9 cell NiMh battery; any way to work out how long I would have to charge the same 2000mAh stick then?
    Post edited by Victor Frost on
  • Dr. TimoDr. Timo
    edited March 2010
    If it is 9.6 volts then thats probably an 8 cell NiMH. As for the higher voltage, I don't think it matters, the way it works out is that the cell's voltage will determine what voltage the charger is driven to. What can be problematic is if the charger has some sort of charge termination features that relies on having a 9.6 volt cell. Usually (i.e. the cheapest way) is for the charger to cut the current when the battery pack reaches ~1.6 volts per cell. So in an 8 cell quick charger this limit will never be reached by a 6 cell battery before there is dramatic failure of the battery pack!

    Note that the above statement of mine regarding the safety of charging NiMH's only applies when charging is relatively slow (>~ 10 hours).

    So if you use the quick charger then do the calculation with the amperage like before and set an alarm clock. Also if you have a multimeter you may want to monitor the voltage of the cell once in a while.
    Post edited by Dr. Timo on
  • OmnutiaOmnutia
    edited March 2010
    $40 charger? Try $13. I've been looking at getting one of these as it has four separate channels, so you can charge any combination of batteries. It also cuts off automatically when the battery reaches full charge.
    Post edited by Omnutia on
  • Dr. TimoDr. Timo
    edited March 2010
    I think Sonic is talking about battery packs such as are found in RC vehicles, not normal AAA batteries.
    Post edited by Dr. Timo on
  • OmnutiaOmnutia
    Ah, well that makes sense.
  • Dr. TimoDr. Timo
    edited March 2010
    Although, that $40 charger can charge all my nimh batteries and is smart enough to know when to stop charging. -_- Maybe I should buy it after all...
    Depends on what you need. If you are into RC and plan on perhaps some day moving up to LiPO batteries, then getting one of these babies may be even better. Those things will charge pretty much anything that can hold electricity.
    Post edited by Dr. Timo on
  • Victor FrostVictor Frost
    edited March 2010
    Although, that $40 charger can charge all my nimh batteries and is smart enough to know when to stop charging. -_- Maybe I should buy it after all...
    Depends on what you need. If you are into RC and plan on perhaps some day moving up to LiPO batteries, then getting one ofthesebabiesmay be even better. Those things will charge pretty much anything that can hold electricity.
    Oh yeah, LiPo is definitely one of my next upgrades. It's just that, for now, they are too expensive. After I get LiPos, though, my next upgrade would be from my current HPI E10 chassis to This Baby.
    Post edited by Victor Frost on
  • Dr. TimoDr. Timo
    After I get LiPos, though, my next upgrade would be from my current HPI E10 chassis toThis Baby.
    Niiiice. I'm seriously considering this one, two 2s lipos in series == 60+mph!
  • Victor FrostVictor Frost
    After I get LiPos, though, my next upgrade would be from my current HPI E10 chassis toThis Baby.
    Niiiice. I'm seriously consideringthis one, two 2s lipos in series == 60+mph!
    That's pretty damn sweet. I picked the cylcone because it's the next step up from my E10 in terms of drifting chassis. Also, Tower Hobbies for the win. Their shipping time to my house is INSANELY quick, and the fact that they offer parts lists for their cars is great.
  • StarfoxStarfox
    Need a charger. Anker is fine, right? Looking at this one.
  • Victor FrostVictor Frost
    Yeah
  • DromaroDromaro
    Anker is the best.
  • sK0pesK0pe
    Dromaro said:

    Anker is the best.

    Cables are still shoddy, the micro USB to USB cable housing / covering separated (exposing the interior cables) on one while the other is fine.
  • RochelleRochelle
    I use the 6 port.

    Also recently upgraded my external batter because I can't find the charger for my old one that didn't use micro USB.
Sign In or Register to comment.