More than one battery

Discussion in 'American RV's' started by Lampie, Sep 17, 2008.

  1. Lampie

    Lampie Read Only Funster

    Nov 2, 2007
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    My problem is I only have one small leisure battery on the RV ( 85 ahr ) would love to add more. It is not as simple as it sounds to me. ie you don't just add more and link them together. I have seen isolators that allow you to connect an array of batteries to them so that they all charge together but discharge equally. What should I do. realise I need to know my battery charger can handle charging the new larger supply.


  2. Groundhog

    Groundhog Read Only Funster

    Jun 18, 2008
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    Hi Lampie

    You may remember we exchanged PM's a few weeks ago just after I took delivery of my Santara.

    Mine was the same with only one 75 ah battery but just enough space in the tray for a second one but not sufficient space for anything larger. I decided to have the dealer put 2 new 75 ah batteries on connected in parallel which he assures me is the correct way to do it.

    I've not used it in anger yet but will be off to France for a few weeks soon which should give them a reasonable test.

    Hope this helps
  3. Digger Driver

    Digger Driver Read Only Funster

    Oct 4, 2007
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    You can rack as many batteries as you like and all it will do is make your charger work harder!
    I have 3 on my bus. I had 3 on the last one too!
    3 years later i'm still waiting for a problem to arise!
  4. pappajohn

    pappajohn Funster Life Member

    Aug 26, 2007
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    YO11 2BD
    hi lampie,

    i wouldnt worry too much about your charger...:Cool:
    when you consider a battery charger from a motoring shop is usually around 4 to 6 amp hour and you expect it to charge a 60/65amp hour car battery, which it does quite well.

    your onboard charger would, i expect, be around 12ah and it will only output 12ah max so will take longer to charge two batteries.
    same applies to your engine alternator, it will only output its max ampage.

    dont forget you probably wont let the batteries get flat anyway so it wont work as hard.

    go your second battery, i would suggest you buy two new ones as the old one may not be capable of holding a full charge and as such will pull the new one down to match.

    connect the batteries pos to pos ....neg to neg otherwise you'll get 24volts and blow the lot and use at least 50amp wire (7mm sq) and fit a fuse at BOTH ends as close to the batteries as possible.
  5. Douglas

    Douglas Read Only Funster

    Aug 22, 2008
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    South Wales,
    Batteries, the more the merrier

    I live in my van mainly in Portugal And wild camp every where, so I never have access to a power plug in.

    I have built onto the chassis a tray to carry 6 X 50amp batteries, this gives me 300 amp/hour. to charge these I have 200 watts of solar panels on the roof, I run tv for about 4 hours/day and a computer for about 5 hours a day I never run out of 12 volt even on cloudy days.

    Horses for courses, build a system that suits your needs.


    p.s. Presently in Cochem on the Mosel in Germany using a WiFi dish antenna to link into the internet.

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