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12v battery. How is it charged?

Discussion in 'Prime Technical Discussion' started by Dmitriy Sokol, Mar 3, 2017.

  1. Dmitriy Sokol

    Dmitriy Sokol Active Member

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    Does anyone know if the 12v battery is only charged by ICE? What happens if I use EV mode for weeks, without ICE kicking in? Would it be beneficial to trickle charge it once a week or so? Thanks!


    iPhone ?
     
  2. 34Hupp

    34Hupp 1934 Hupmobile - Americas 1st Aerodynamic

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    #2 34Hupp, Mar 4, 2017
    Last edited: Mar 4, 2017
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  3. fuzzy1

    fuzzy1 Senior Member

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    That isn't true of any previous Prius, so it seems highly unlikely for your Prime.

    If charged only by the ICE, the 12V would become a problem within a very few operating hours, not weeks.
     
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  4. I'mJp

    I'mJp Senior Member

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    It's charged by the power conversion unit that sits not far from it. It is the transmission and alternator of the car. It has it's own liquid cooling system.
     
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  5. bisco

    bisco cookie crumbler

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    it should also charge when plugged in. unless they changed it from the pip.
     
  6. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    Lets assume that the 12 volt battery is charged in a similar fashion to other Prius. In that case this (boring) demo goes over it from 15:10 to 18:00 (on the Prime the 12 volt battery is under the hood, not as stated for the Gen 2, in the back hatch)

     
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  7. Andyprius1

    Andyprius1 Senior Member

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    A great explanation. TY
    In layman’s therms. A potential of 14.5 volts, about becomes available when car is in ready. If the 12V requires charging then current flows and returns the battery to design level. When both sides, the Dc source
    and the 12V are equal, current ceases to flow and charging is complete. Until the next microsecond.
    The charge you showed looks great.
     
  8. Andyprius1

    Andyprius1 Senior Member

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    I think you are right.
     
  9. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    It would still be worthwhile to hook up to an external smart charger, if the car regularly sits for a day or three.
     
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