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jaycocreek's avatar
jaycocreek
Explorer II
May 04, 2022

Lifepo4 float setting?

I have not had to deal with a float setting so far with PWM controllers but I have a Victron 75/15 coming tomorrow and reading up on the settings,it is confusing especially the float setting..Some say float will shorten the life of a LFP battery and others say hogwash..

Float at what setting for a 100ah LFP battery that settles at 3.3+..?

Any input welcome...

125 Replies

  • Don't see what PWM vs MPPT has to do with it. The battery doesn't care--solar is solar. Voltage goes down every night, which sort of counts as floating for any type of battery, depending on the scenario.

    The concern over float voltage with LFPs seems to be more with converters left on for long periods. With solar, float voltage settings should also depend on the scenario? Is this just for when camping or for when the RV is sitting at home for long periods?

    If the latter, the usual story is run the LFP down to 50% SOC and disconnect. Get your 12v from the converter.

    While camping off grid on solar I guess it depends on how many days/weeks in a row and whether you get to full charge or not and even when during the day that is. It still gets dark at night though.
  • It's been said a bunch...pick your posion. Are you cycling them daily or storing the trailer for awhile then using it?

    It will interesting after a 2-3 years with many new folks getting lfp what the survival rate will be of said batteries. With so much mixed info being regurgitated of how to use (charging, absorb, float) the batteries.

    As long as you can get the cells to balance and have your SOC meter sync to the capacity of the battery bank occasionally life should be good.

    What voltage is need for "your" batteries to accomplish this?
  • Then I wouldn't bother floating it. It's a miniscule amount more charge and Li's don't care if they're fully charged.
  • 2oldman wrote:
    Shouldn't the battery maker have that info?


    For this particular battery,there impossible to communicate with and the reason why I did not buy another one of there batteries when I needed another..The battery I did get instead of there brand says float 13.8 which is higher than recommended everywhere I look..

    I don't think some of these cheap batteries have very good customer service,some do,some don't.

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