Solar powered battery maintenance for multiple bikes

Discussion in 'The Garage' started by mokosai, Sep 30, 2019.

  1. mokosai

    mokosai Been here awhile

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    So, I need to park motorcycles over the winter in a spot that has no electricity. I would like to hook up battery tenders to the bikes, and I was considering the easiest way to be a cheap bastard and yet have a solar panel maintaining motorcycle batteries.

    How about a single 60 watt solar panel, and two cheap battery charge controllers hooked up to it in parallel, with a motorcycle hooked up to the battery connections of each of the 3-stage charge controllers? I think the two battery charge controllers can probably share a solar panel. I guess that when there isn't full sunlight hitting the panel to charge controllers won't really be doing anything for the battery, but that's okay, because I'm really just trying to maintain charge.

    Or alternatively, can I be really really cheap and hook up both motorcycles in parallel with one another to a single charge controller? The only problem I can foresee is that the batteries will try to equalize when connected first connected in parallel, so I probably want a current limiting resistor somewhere in series to make sure that the two batteries can only transfer charge between themselves at a couple of amps max.

    Thoughts?
    #1
  2. 51%

    51% ReadyToRide

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    Just buy two cheap solar battery maintainers, they’re only like 10w more or less.

    Solar controllers usually state do not connect to the PV panel with the battery bank not connected. Potentially when you unplug a bike -if the PV panel is lit up and connected- you could kill the controller.
    #2
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  3. JR356

    JR356 Long timer

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    Best idea is to pull all the batteries,bring them home and rotate them on a single charger,or get one of the multi bank chargers from BatteryTender or ?

    JR356
    #3
  4. mokosai

    mokosai Been here awhile

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    How embarrassed should I be that this didn't occur to me as the cheapest and simplest option of all?
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  5. MrPulldown

    MrPulldown Long timer

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    Or you can just do nothing. That is what I typically do. If I want to do a little more, then I unhook the battery and leave it in place. Next option is to pull the battery, tape up the terminals (so there is no accidental shortage), and set opn the garage shelf. I never leave a battery on a charger. Doesn't seem like there is a reason for the battery to discharge over the winter. If I have the battery pulled I will give it a charge before I install it in the bike. If I really wanted to "take care" of the battery, I will probably throw a trickle/tender on it for a couple of days each month.
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  6. RetiredandRiding

    RetiredandRiding Retired to Ride Supporter

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    Don't hook up two batteries to the same tender at the same time. Could be bad news.
    #6
  7. Grreatdog

    Grreatdog Long timer Supporter

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    If you want to go the solar route, you dont need that much power. A pair of 5w Battery Tender panels with built in controllers kept my pair of boat batteries fresh for ten years.

    Even though they had to run bilge pumps, 5w was enough. I replaced the batteries when I sold the boat just so buyers wouldn't freak at ten year old batteries even though they worked perfectly.

    There are probably better things out there now. This design is at least 15 years old now. But they worked perfectly in a moored boat with no power. In my experience, even this is more power than you need for a maintenance charge:

    https://www.amazon.com/Battery-Tend...ocphy=9007937&hvtargid=pla-436302373665&psc=1
    #7
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  8. Andyvh1959

    Andyvh1959 Cheesehead Klompen Supporter

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    I'm building my shop garage right now. It will also have four 220watt solar panels on the south of the roof to power the LED lights I am using to light the garage. I already have the solar panels, charge controller and DC breaker panel. I have 11 bikes to keep charged, so I'm thinking of using the solar panel output to also power a bunch of connections for my bikes. Anyone done this? Or am I considering a complicated setup to keep my bikes charged?
    #8