NiCads, connecting NiCads for tools.

Discussion in 'General Electronics Chat' started by bundick, May 27, 2012.

  1. bundick

    Thread Starter Active Member

    Dec 19, 2007
    DSCF4834.jpg DSCF4835.jpg

    Wife's "Wiffer stick Vac" battery ran down to less than 2 Minutes Running time.
    Six NiCad's, 1.2V 1500 Mah. I'd put 2000 Mah's in there if I could. Whaddayathink?

    How do I safely solder (or other) each battery to the next with my Replacement Cells?

    I have a small wattage Soldering iron. Never heated a NiCad up like an Iron would. I wonder if it's smart? Or suddenly chaotic....with Krispy Kritters all over the shop?

    Any experienced help out there?:)
    Last edited: May 27, 2012
  2. strantor

    AAC Fanatic!

    Oct 3, 2010
    Those who do this routinely use a "battery tab welder" but I don't see it being cost effective for you to buy or build one for just this one project. I've soldered wires to regular AA batteries but they do get super hot. I assume it would be a bad idea to do it with a NiCad.
  3. paulktreg

    AAC Fanatic!

    Jun 2, 2008
    I've soldered NiCads successfully in the past but you'll need a 50W+ soldering iron. I found the solder took fairly easily if you first roughed up/scratched the area to be soldered with a file or something similar.
  4. bundick

    Thread Starter Active Member

    Dec 19, 2007
    50 Watts eh?
    This plastic cage will hold them in place for me. I may try soldering, if I don't come up with any other answer after awhile.
    What I see is a new Stick Vac though. This one's six years old.
    Batteries are going to be $35....don't know yet. Maybe Tuesday when everybody's back from the weekend more ideas will come up. :)
  5. Llamarama

    Active Member

    Feb 1, 2010
  6. crutschow


    Mar 14, 2008
    You can buy NiCads with solder tabs welded into place.
  7. bundick

    Thread Starter Active Member

    Dec 19, 2007
    That would work.:)
    Got any idea how I'd search for that?:confused:

    I'm about to contact the Mfg of those heavy duty NiCads to see what they have to say about guys in the field doing the soldering.
    If I get anything we can use I'll come back to this thread.

    I am so dull witted.
    Years ago I worked on a little device that used a 12 V-1.3a battery.
    It had a mini-charger built into the Power supply that kept the Battery charged. The Terminal ran on the battery.
    I wish I'd paid more attention to the Circuitry. That would be handy info now.
  8. PackratKing

    Well-Known Member

    Jul 13, 2008
    I routinely make up battery packs for power tools.......
    I use my Weller 350 watt gun, "Oatey" brand or similar flux for copper pipe sweat soldering, and lead free plumbing solder.

    The all-important issue is the shortest possible dwell time on any battery to solder on the strap or a wire. the iron itself must be hot for adequate speed in heat transfer.

    Both wire / strap and battery surface must be shining. I make slices of solder, and put it in flux between wire and battery so the joint is made without fumbling 3 different items. Cool the joint asap with a damp washcloth or sponge, and then remove excess flux w/ denatured alcohol.
  9. bundick

    Thread Starter Active Member

    Dec 19, 2007
    Oh PackRat I'm glad to see that post.
    I'd heat sink the Battery tab with Hemostats. I always used those on my 'real' job years ago.

    I sent an email off to the Chinamen to see what they recommend for us. Wont get answered till tomorrow though.
  10. gerty

    AAC Fanatic!

    Aug 30, 2007
  11. bountyhunter

    Well-Known Member

    Sep 7, 2009
    Using a high wattage iron to solder on tabs can damage the insides (like the vent). I use a tiny dot of acid flux on the battery surface and that makes the solder flow out instantly even with a 22W iron, then wash it off thoroughly. Acid flux is typically taboo for electronics, but in this case it's less harmful than cooking the battery with a high watt iron.
  12. bundick

    Thread Starter Active Member

    Dec 19, 2007
    Great, many thanks.
    It's so hot today I'm about done for.
    Somebody come take me fishing.....:)
  13. BillB3857

    AAC Fanatic!

    Feb 28, 2009
    Battries + stores will rebuild battery packs. I found I could by 2 NEW for $10 more than the want to rebuild only one.