Battery charge program for prime - AGM?

Discussion in 'Prime Main Forum (2017-Current)' started by Professor Chaos, Apr 24, 2020.

  1. Professor Chaos

    Professor Chaos Junior Member

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    Hi all - like many others, I've not driven my Prime for about 6 weeks and the 12V battery seems completely discharged (the car is not responsive to anything). It's the original battery for a 2017 Prime.

    I just bought a CTEK MXS 5.0 charger, and am trying to figure out which program to use.

    There is a "normal" program which the CTEK manual says to us for "many AGM batteries," and an "AGM" open for use with "most AGM batteries like Optima and Odyssey". Should I use the "normal" or "AGM" mode for my Prime battery?

    There is also a "Recondition" option which the manual says to "use to return energy to the empty WET and Ca/CA batteries." But the manual also illustrates an "AGM RECOND" mode. Would I want to use AGM RECOND for my battery?

    Thanks much!
     
  2. sam spade 2

    sam spade 2 Senior Member

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    To get it back up near to a full charge.......or more accurately to TRY and get it fully charged......it will make absolutely no difference which one of the NON-recondition modes you choose. There really isn't that much difference.
    I suggest that you use "normal" to start with.

    AND....the recondition mode is largely useless; if any apparent gain is made it will be very short term.
    That mode is not intended to be used on a dead battery.

    Note: Once a battery is THAT dead, it likely is a gonner even if it appears to charge back up.
     
  3. Rob43

    Rob43 Senior Member

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    My experiences when using an automatic/computer chip based charger is "most" of the time they won't revive a totally dead 12v battery and they go into a fault mode. If you give up at this point, you'll be spending $$$ for a new battery.

    On the half (50/50) chance that your 12v battery is actually revivable, you'll need to first charge it with a Dumb Manual 12v charger. A manual 10 amp charger will Force Feed your dead battery, what this does is it brings your depleted 12v battery up to a point where your Smart automatic charger can take over and finish the job. Like I said, there are no guarantees this will work, but it might work as I've been successful using this method.

    12v Battery Is Discharging, Re-Charge Now ! | PriusChat


    Rob43
     
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  4. Professor Chaos

    Professor Chaos Junior Member

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    Yeah, the CTEK doesn't seem to recognize that there's a battery there.

    It's only three and half years old, but has been stored without charging for 5 weeks each of the past three summers. So it might be time to call for a battery service... if I can find someone to come out!
     
    #4 Professor Chaos, Apr 24, 2020
    Last edited: Apr 24, 2020
  5. Rob43

    Rob43 Senior Member

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    Do you have a Harbor Freight Tools near you ?

    If you do, they have a manual 10 amp (2,10, 50 Amp Start) Manual* charger for ~$55 dollars. They also have a 20% coupon currently, so you'd be at ~$44 dollars.
    www.harborfreight.com/10250-amp-12v-manual-charger-with-engine-start-60581.html

    If it were me, I'd charge at 10 amps for ~4 hours. Then I'd let it rest for ~30 minutes, then I'd connect your CTEK.

    If you don't own a voltmeter, buy their cheapo (Red )~$6 dollar unit.
    www.harborfreight.com/7-function-digital-multimeter-63759.html



    Rob43

    * It needs to be a MANUAL 12v charger for this to work.
     
    #5 Rob43, Apr 24, 2020
    Last edited: Apr 24, 2020
  6. Mendel Leisk

    Mendel Leisk Senior Member

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    With the CTEK just use regular charge mode (no snowflake symbol). The Prime has a regular lead acid battery, not AGM.

    Manual says to use snowflake only for "spiral wound AGM" IIRC, like Odyssey and Optima (the ones that look like a 6-pack). Even rectangular case AGM (like 3rd gen OEM), just use reg charge cycle.
     
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  7. jerrymildred

    jerrymildred Senior Member

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    Just to confirm what @Mendel Leisk said. The Prime (and all Gen 4 afaik) use a lead acid battery. Note the caps on top of the battery case.
     
  8. sam spade 2

    sam spade 2 Senior Member

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    I got one of those a few years ago. BIG mistake.
    It has an uncalibrated meter and the needle stays in almost exactly the same place on the 10 setting as it does on 2.
    Maybe there will be more of a difference if the battery is really low......but somehow I doubt it.
    It is heavy enough that it might make a good boat anchor. :eek:
     
  9. sam spade 2

    sam spade 2 Senior Member

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    Conventional lead acid batteries do NOT like to be left alone for long periods.
    Your 3rd year of 5 months consecutive down time probably has finally killed it.
    When you do replace it, you should seriously consider getting an AGM design.
    They are a bit more expensive but are overall better in every way.
    And should tolerate your down time better.
     
  10. Mendel Leisk

    Mendel Leisk Senior Member

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    Also, the CTEK's "reconditioning" I believe is meant just to be used occasionally, say once a year at most. If you're not sure I wouldn't use it. It's intent is to desulphate the battery IIRC?
     
    #10 Mendel Leisk, Apr 25, 2020
    Last edited: Apr 25, 2020
  11. Rob43

    Rob43 Senior Member

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    Wow, I can't believe for a moment that a guy like you depends on the meter. BIG Mistake.


    Rob43
     
  12. Professor Chaos

    Professor Chaos Junior Member

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    Well, a jump started her up. I drove it for about 20 minutes and then hooked up the CTEK, which is working on it now...

    Is there a straightforward way to assess whether the battery needs replacement at this point? I have a DMM to check voltage.
     
  13. bisco

    bisco cookie crumbler

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    after you have charged it up, leave the hood popped, and check the voltage every day. when it stops dropping two days in a row, you'll know if it's good or bad.
     
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  14. sam spade 2

    sam spade 2 Senior Member

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    Not all meters are created equal.
    I can't believe that you thought that remark would be somehow helpful to anybody.
     
  15. sam spade 2

    sam spade 2 Senior Member

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    Not exactly straightforward.
    The first clue is that the CTEK says it is fully charged, but that might take up to 48 hours.
    After that, if it sits for 24 hours without the charger connected and the voltage is still 12.5 or more, odds are that it will be good for a while yet........if the CTEK is left connected.
     
  16. Rob43

    Rob43 Senior Member

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    Well, I'm glad you now realize that all meters are not created equal.

    And my comment was directed at you.


    Rob43
     
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  17. sam spade 2

    sam spade 2 Senior Member

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    Stuff it.
    :mad:
     
  18. Rob43

    Rob43 Senior Member

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    sam, I am sorry that I've hurt your feelings.


    Rob43
     
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  19. jerrymildred

    jerrymildred Senior Member

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    I have never in my life had a car sit idle for more than three weeks, and that was only a few times over the past 45 years. Not sure where you're getting this 5 month notion.

    But, yes, AGM is a better battery. Just not better enough for me to spend extra on it given how long my batteries last anyway.
     
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  20. Salamander_King

    Salamander_King Senior Member

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    I am sure the comment was meant for the OP. But he has misquoted OP's comment on 5 weeks not 5 months.
    As for the use of AGM battery for PRIME and Gen4, my understanding is that there is no AGM battery in group size that would fit. If such an AGM battery exists, I would like to know, although I don't think I will be needing to replace my 12v for at least several more years, possibly never before my next car.
     
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