Forum Discussion

Huntindog's avatar
Huntindog
Explorer
Jan 09, 2016

Adding two new 6 volts to existing six volts

I am considering adding two new 6 volts to the two year old ones I have. I am aware, and agree that in most cases this is not a good idea as the old batteries will draw from the new ones.

But my usage is somewhat unique. My batteries are always either being charged by the convertor, or being used to power loads in my TT. They never sit at rest.
So in my thinking, I don't believe that the old batteries will harm the new ones. At least not when being charged.. When powering loads, I think the new ones may do a little more work than the old ones and thus shorten their lifespan slightly. But no big harm done if that is the case.

Thoughts?

47 Replies

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  • time2roll's avatar
    time2roll
    Nomad
    Jan 10, 2016
    Go for it. No worries, no issues.

    Yes the existing two year old batteries may only have ten years left in them.
    The newly added GC2 will probably only last the ten years instead of going twelve.
    Big whoop-de-do
  • RJsfishin's avatar
    RJsfishin
    Explorer
    Jan 10, 2016
    Huntindog wrote:
    rjxj wrote:


    Just curious about the SG. Have you equalized or top charged at a higher than normal voltage?


    Never did anything other than let the converter take care of it.

    X2 Smart man !
  • NinerBikes's avatar
    NinerBikes
    Explorer
    Jan 10, 2016
    Purist POV, equalize charge to 16.0V and 5 amps constant current the older batteries, and hook all 4 up.

    Strictly by the book? Don't mix and match them. Use the old pair while the new pair fully recharges, and then vice versa. They shouldn't be used at the same time together. Bad idea to mixed aged batteries with new fresh batteries.
  • Huntindog's avatar
    Huntindog
    Explorer
    Jan 10, 2016
    rjxj wrote:


    Just curious about the SG. Have you equalized or top charged at a higher than normal voltage?


    Never did anything other than let the converter take care of it.
  • azrving's avatar
    azrving
    Explorer
    Jan 09, 2016
    The new battery wont preform as well until it cycles 15 to 20 times or so. It just seems better to connect them after the new one is broke in.

    Just curious about the SG. Have you equalized or top charged at a higher than normal voltage?
  • Huntindog's avatar
    Huntindog
    Explorer
    Jan 09, 2016
    rjxj wrote:
    I have the same set up. I would run on the new batteries first for 20 cycles or so and not deep discharge them. Then when fully charged connect them and carry on. Have you checked the specific gravity of the ones you have now?


    No on the SG. Voltage at rest is identical.
  • azrving's avatar
    azrving
    Explorer
    Jan 09, 2016
    I have the same set up. I would run on the new batteries first for 20 cycles or so and not deep discharge them. Then when fully charged connect them and carry on. Have you checked the specific gravity of the ones you have now?

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