Register now to get rid of these ads!

Technical Battery Charger Voltage

Discussion in 'The Hokey Ass Message Board' started by blowby, Nov 14, 2020.

  1. Me too! Craftsman from the 60’s

    Sent from my iPhone using The H.A.M.B. mobile app
    Truck64 likes this.
  2. Truck64
    Joined: Oct 18, 2015
    Posts: 5,317

    from Ioway

    See this in OT forums and vee-hickles all the time, especially Diesels with big 1000 CCA dual batts wired in parallel. They buy a $5 1/4 amp wall wart charger from Harbor Fright and want to know why it won't charge them up.

    The idea is to "size" the charging amps to the ampere hour capacity of the battery. About 10% of hour rate (not CCA) or so is considered a "trickle" charge, fast enough to charge in a reasonable amount of time, not so hot as to damage the battery components. Those big chargers on wheels have maybe a 50 amp setting that will get a dead battery ready to go in an hour but that isn't necessarily the way to go. In the case of dual batts wired parallel what we have now is one Big Ass battery. A nice slow "trickle" charge is maybe 15 or 20 amps.

    Lead acid batteries will always outgas moderately for a time towards the end of what's called the "absorption phase", this is beneficial and equalizes the cells and mixes up the electrolyte. But it needs to be minimized, a 3/4 amp charger would be bubbling away for weeks. It will work, but it's like trying to fill a swimming pool with a soda straw. Some of the better chargers will charge them up all the way, "equalize" routines and the rest of it.

    I use the old school "dumb" chargers and let them cook overnight, also run the battery down a hefty bit on the headlights and repeat a couple times. This will remove some of the permanent sulfation on older batteries. When they get juiced up good, I put 'em on the tenders.
  3. Took a picture today of my 60 year old battery charger. :cool:Used it today on my plow truck.:) Don't make stuff like this anymore.:( Craftsman
    Petejoe and Truck64 like this.
  4. Model A Vette
    Joined: Mar 8, 2002
    Posts: 1,072

    Model A Vette

    I would guess that my charger is 50-60 years old. It has a meter like the one in post 33.
    It does not do 6volts nor have a light on it.
    I brought it home from vietnam in 1971.
    It was abandoned with a navy river boat.
    It worked for a few years and then quit.
    I had a "noisy" trans from a computer terminal I worked on. My dad got me a BIG diode and wired it up for me and I added a circuit breaker.
    It will start charging a DEAD battery at 2 amps and raise to 4 amps after a half hour. I usually leave it on for 24 hours and it goes down to 2 amps when it has charged the battery. It reads 16 volts when I first hook it up. It reads somewhat lower when finished.
    The transformer was part of a recall I did on a great deal of terminals. I think I kept 3 more as spares but never needed them.
    ct1932ford likes this.
  5. blowby
    Joined: Dec 27, 2012
    Posts: 8,384

    from Nicasio Ca

    I need to replace my corroded battery charger alligator clamps. What is the best metal to withstand the corrosion, copper, stainless? Also, I'd like the clamps that look like this and don't snag on everything. Is there a different name for them?

  6. Cosmo49
    Joined: Jan 15, 2007
    Posts: 1,333


    If they are functional and corroded, leave them in Coca-Cola for a day?
    blowby likes this.
  7. blowby
    Joined: Dec 27, 2012
    Posts: 8,384

    from Nicasio Ca

    Good idea. I did find the whiz bang clips too, made by Mueller.

    Cosmo49 likes this.
  8. Petejoe
    Joined: Nov 27, 2002
    Posts: 11,250

    from Zoar, Ohio

    Found an even better one for 30 bucks.
    Dayton Heavy Duty 30amp.

Share This Page

Register now to get rid of these ads!


Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.