Re: nimh replacement batteries for nicad cordless drill

Fred Bloggs wrote:

I had a craftsman 14.4v cordless drill that was in good shape except
for the ni-cads losing their charge capacity. I jolted each one of
the cells a few years ago and got great results at that time. Now
that the problem resurfaced...I tried it again with no luck. Since
NiMH cells were available, I decided to replace all the cells with
these. For some reason both of the two packs never seem to get much
of a charge. Is there something special these type packs need in
terms of charging? Or is there something inherently missing by using
a nicad charger on a NiMH battery pack?

Sounds like your charger is on the blink, and there was nothing wrong with your NiCd pack...


IIRC nickel hydride cells don't have the peak capacity of a similar NiCd, so they're not as well suited to things like drills, where you need lots and lots of torque for brief periods.

Cheers,

Phil Hobbs
.

Relevant Pages

  • Re: Rx pack chargers
    ... How can it charge 30 cells at once? ... It says the 977 will do 2 packs, ... When I charge the 2 packs for the Emaxx I have a separate charging harness ...
    (rec.models.rc.land)
  • Re: LiPos in parallel?
    ... sizes of packs available. ... to have them at the same voltage level before connecting the leads. ... cells would be any more dangerous than charging LiPo's is. ... *once you are sure they are at an equal state of charge*. ...
    (rec.models.rc.air)
  • Re: LiPos in parallel?
    ... you wouldn't see so many different sizes of packs available. ... The key should be to have them at the same voltage level before connecting the leads. ... Alghough I don't recommend any connection that would cause cause more than 1C current to flow into a cell, I don't think paralleling equal voltage cells would be any more dangerous than charging LiPo's is. ... The thing here is that as long as the packs are of the same chemistry/construction style and from the same manufacturer, *even if the cells are of differing capacity* you can connect two packs in parallel *once you are sure they are at an equal state of charge*. ...
    (rec.models.rc.air)
  • Re: Circuit Design Q. - battery charger
    ... bright sunlight in perfectly clear weather. ... cells so you have sufficient voltage to charge the batteries? ... will be very unlikely you will give the battery much of an overcharge. ...
    (sci.electronics.design)
  • Re: Triton setup for 8 cells 1000 mAh - Please help :)
    ... I had a similar problem with a couple NiMH packs when I first got them. ... OK for small packs at a low charge rate, but when I used them on larger ... charge is very important for NiMH cells. ...
    (rec.models.rc.air)