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Solar Trickle Charger for 12V Battery?

Discussion in 'Gen 3 Prius Accessories and Modifications' started by UNCBlue, Dec 12, 2016.

  1. UNCBlue

    UNCBlue New Member

    Joined:
    Sep 22, 2016
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    Location:
    North Carolina
    Vehicle:
    2014 Prius
    Model:
    Four
    I've done a lot of reading on here about the various options for maintaining the 12V battery when the Prius is parked for an extended period of time. My 2014 Prius Four not IV will be parked pretty regularly for about 5 or 6 days at a time, but probably not longer than a week or two at most on occasion.

    The most appealing option to me seems to be the small solar panels produced by VW which can sit in the rear window and be wired directly to the 12V battery. They are cheap, and from my understanding can't supply enough voltage to over-charge the battery. I am not as familiar with these systems as I would like to be, so I have a couple of questions for anyone more experienced than myself:

    Wiring: How exactly should this be wired to the battery? I know the cigarette lighter outlet is not hot when the car is off, so that's a no go. I also understand that the OBDII port is located in the front dash and may not be the ideal method for wiring this kind of setup. I was hoping to just leave the solar panel in the rear window where the battery is located, but I would need a secure way to wire it directly to the battery. I have also heard mention of diodes to prevent the panel from discharging the battery in the dark. A simple explanation of how to safely wire this would be fantastic.

    Also, can the setup be connected while I am driving the car, or would it need to be disconnected every time I start up? I'm pretty sure I don't have to worry too much about the battery draining over time spans of less than a week, this just seemed like a simple way to ensure I never ran into any problems.

    Any advice would be much appreciated, thank you!
     
  2. fotomoto

    fotomoto Senior Member

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    Location:
    So. Texas
    Vehicle:
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    NEVER, EVER attach a power output device to the OBD port!!!!!!

    Lots of RV and boaters use solar chargers. I haven't used one so I can't offer any advice on those but I do use a battery tender on my '06. It comes with a bolt on hook up for the battery terminals (so you only do this part once) and a pull-a-part quick disconnect on the other end that connects to the charging unit thus it becomes plug & play. The quick connect is run through the hole for the battery vent tube to the outside just behind the right rear wheel. I route an extension cord so I see it as a reminder to unplug before driving away. The tender charges to full and then enters a maintenance mode after that so it can be left for long periods of time and is a very popular storage solution in the motorcycle world. They can be found just about anywhere auto care products are sold.
     
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  3. Prime_Number

    Prime_Number Junior Member

    Joined:
    Feb 6, 2017
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    Location:
    San Diego
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    In my Prius Prime Premium (2017), I'm very happy with my Battery Tender 021-1164 10W Solar Panel Charger and an OBD2 male connector. I wired the charger to the power and gnd pins, nothing else. It's been used over a 4 week period in October in So. Cal. The previous 4 week period saw the 12V die and the car doors wouldn't even unlock. Now, I just plug in the OBD2, set the panel in the windshield, prop it up with a yoga block and face the car south.
     
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  4. Grit

    Grit Senior Member

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    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    And then

    :ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO:
     
    #4 Grit, May 11, 2019
    Last edited: May 11, 2019
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  5. fotomoto

    fotomoto Senior Member

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    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    After recently getting a new Clarity, I'm not driving my CMax as much so I too got a small, $20 solar trickle charger. Just wired it straight to the battery in the trunk with a simple disconnect in between. I mounted it on the right side that typically faces due east during the day while parked at home so it gets about 4 hrs of direct sunshine.

    OBD port is still used for ScanGuage II.

    FWIW

    IMG_4589.jpeg IMG_4588.jpeg
     
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