Exasperating misinformation on 12V battery

Discussion in 'Prime Care, Maintenance and Troubleshooting' started by frederw1701, Jan 16, 2025 at 8:41 PM.

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  1. frederw1701

    frederw1701 New Member

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    2018 Prime.

    I Googled because it was such a simple question and even asked a battery store, showing them a picture of the battery.
    Putting them all together, I have been told that the 2018 Prime battery is in the trunk, that it is AGM, that the computer will refuse to charge a flooded battery, and that it's sealed and the caps are not removable.
    Someone on Reddit took a screwdriver to the caps and found liquid underneath.
    Toyota's manual only tells me that batteries are hazardous. Good information but not news.
    So --
    It's flooded, right?
    I can check the electrolyte?
    I should check the electrolyte?
    There's a tool less likely to damage the caps than a screwdriver?
    What exactly is it called or can I have a link?
    upload_2025-1-16_17-33-10.jpeg
     
    #1 frederw1701, Jan 16, 2025 at 8:41 PM
  2. bisco

    bisco cookie crumbler

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    you could check it, but most people don't. there are some threads here if you can find them.
    also on replacement size and available options.
     
    #2 bisco, Jan 16, 2025 at 9:20 PM
  3. frederw1701

    frederw1701 New Member

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    Given that it's six years old I feel like putting more than usual care into it to postpone the expense of a new one. Plus I'm so old I remember when that was just one of the things you did, like reading the spark plugs.

    Do I understand right that the cell by cell information from electrolyte density has some advantages over just measuring the battery voltage?
     
    #3 frederw1701, Jan 16, 2025 at 9:36 PM
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  4. bisco

    bisco cookie crumbler

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    i don't know much about 12 volt batteries. i do know you can get a free load test at most auto parts stores, or even turning on all the electricals and watching the voltage decrease over time, if you understand what's healthy and what isn't.
    i'm old enough to remember checking electrolyte levels on a regular basis. but these days, i'm comfortable caring for the 12v as best i can and replacing when necessary.
     
    #4 bisco, Jan 16, 2025 at 9:44 PM
  5. BiomedO1

    BiomedO1 Senior Member

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    It's flooded, right? Yes
    I can check the electrolyte? Yes
    I should check the electrolyte? Yes
    There's a tool less likely to damage the caps than a screwdriver? Use a nickle or quarter, if you need to get a better grip
    What exactly is it called or can I have a link? Huh??? fill with distilled water to the internal line

    You stated the battery was at 12.5 vdc, so I believe it's in good shape and should last a good long while - if properly maintained...

    FWIW; all gen4 batteries are under the hood - all other Prius are in the trunk or under the seat; past and present.
     
    #5 BiomedO1, Jan 16, 2025 at 11:21 PM
    Last edited: Jan 16, 2025 at 11:29 PM
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  6. frederw1701

    frederw1701 New Member

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    star
     
    #6 frederw1701, Jan 17, 2025 at 3:27 AM
  7. frederw1701

    frederw1701 New Member

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    Thank you for the very informative reply.

    As to the "Huh??", if quarters work well and everyone uses them, there won't be a special tool to ask about or shop for, so the question goes away.

    May it last a long time.
     
    #7 frederw1701, Jan 17, 2025 at 3:33 AM
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  8. vvillovv

    vvillovv Senior Member

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    Love the title of this thread. If removing just the 12v battery from the title, the rest of the title could probably fit in 50% of the posted threads in this forum. :D
     
    #8 vvillovv, Jan 17, 2025 at 6:53 AM
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  9. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

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    The battery model number (345LN1-MF), you would see the MF designation is "maintenance free" flooded battery. It is similar to one in my 2025 Camry. You should be able to use either a regular flooded battery or a maintenance-free battery. AGM does have a different charging profile.
     
    #9 Prodigyplace, Jan 17, 2025 at 7:14 AM
  10. Trollbait

    Trollbait It's a D&D thing

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    The battery should be fully charged when checking the fluid and adding water.
     
    #10 Trollbait, Jan 17, 2025 at 1:02 PM
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