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2nd Dead 12v battery- time for lithium upgrade?

Discussion in 'Prius c Care, Maintenance and Troubleshooting' started by randy8876, Mar 28, 2023.

  1. randy8876

    randy8876 Junior Member

    Joined:
    Sep 3, 2015
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    Location:
    seattle, wa
    Vehicle:
    2015 Prius c
    Model:
    IV
    A few weeks back I drained my 12v battery due to the dome light on too long and since then it hasn't been the same. If the car sits 3 days, the battery will be too drained to start the car.

    This is my 2nd battery to die.

    I feel like the pint sized battery is simply more prone to failure, especially since I've never experienced this in any other car. I have some aftermarket stereo equipment, so that likely cycles the battery a bit extra. I've started searching for a more powerful alternative.

    First off, has anyone tried alternative larger batteries? Like Optima? Or lithium?

    In particular this one has caught my eye.
    https://dakotalithium.com/product/dakota-lithium-12v-60ah-dual-purpose-car-starter-deep-cycle-lifepo4-battery-1000cca/

    It's 60 amp hours and can support high current draw. While expensive, it has an 11 year warranty, so it should be the last battery I buy.

    This battery measures 9.5”(L)x 6.9”(W)x 7.44”(H) vs. 7.62" x 6.81" x 8.75" so it will just barely fit.

    I've emailed the manufacturer asking for their input regarding compatibility.

    Does anyone know of any issues using these in a Prius C?
     
    bisco likes this.
  2. rjdriver

    rjdriver Active Member

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    Three
    If you've had 2 batteries die I suspect that when your car is off, something is drawing more current than it should. Are you sure that stereo equipment was wired correctly? Does it use a separate amp? Or do you have any other aftermarket items installed that could be the culprit? I would find a mechanic that knows how to do a parasitic load test.
     
    Montgomery and Mendel Leisk like this.
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    Vehicle:
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    Touring
    ^Id second that. Try recharging too, with appropriate amperage (see owners manual) smart charger. You can do this without disconnecting battery (contrary to owners manual).

    regarding height diff, the Toyota hold-down bracket is absurdly intolerant of even a mm height difference.
     
  4. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Vehicle:
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    I replaced the dome and trunk lights with LEDs. Another driver in the family is famous for leaving a door slightly ajar for a few days. With the low draw of LED illumination, we no longer have problems.
     
  5. Shahzad Nayyar

    Shahzad Nayyar Junior Member

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    There is a parasitic drain in your car. You need to locate that first

    Posted via the PriusChat mobile app.
     
  6. bisco

    bisco cookie crumbler

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    leaving the dome lite on will kill a prius battery. sometimes they can be revived, sometimes they can't be.
    led's are a good idea, and larger lithium probably is too, with aftermarket equipment.