Lifepo4 settings seem weird

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Ivar Eisma asked May 30, '23

Lifepo4 settings seem weird

I recieved below settings from the battery manufacturer for a 100AH Redodo Lifepo4, but so far have not used them because I got an overvoltage alarm the first hour I did. I've been using the standard Victron MPPT preset for now that seems to work fine.

To me from what I've researched these settings seem way off. Absorption seems super long. Perghaps they are trying to get a cell balance going but 6 hours i've never seem before. And equalization on a Lifepo? I just don't get it.

Do you think they just gave me wrong information? This is the same factory as Zooms, Amperetime etc and nobody used these kind of settings.

Lithium Battery

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Answer 1 · 2023-05-30T12:05:51Z

Alexandra answered · May 30, 2023 at 12:05 PM

@Ivar Eisma

You have edited a profile for lead acid charge. It has temp compensation and equalisation as well as the long absorption. none of which you want for lithium.

Go to the presets, choose lifepo4, turn on expert mode, edit the voltages there to suite your battery recommend values, then save the new battery profile. That will have the correct charge profile for lithium.

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Ivar Eisma commented · May 30, 2023 at 12:32 PM

Thanks, I thought those settings were wrong. I did not edit them myself, that is what the manufacturer recommended to me! But I did not end up using it.

The Victron preset very close to what I thought i needed, thats what I've been using and I think the battery is doing what it's supposed to.

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Alexandra ♦ Ivar Eisma commented · May 30, 2023 at 12:53 PM

Yeah, there was definitely a few steps skipped in setup instructions there. Good thing you paid attention.

I do have one question. I see the battery voltage drops but SOC does not drop. And no current being drawn out. That would be a weird reading. I know it is a custom graph and maybe thats not what you are looking for there.

And you have two shunts, how are they set up on the battery?

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Answer 2 · 2023-05-30T13:16:42Z

Ivar Eisma answered · May 30, 2023 at 01:16 PM

I have one shunt, but connected with VE-cable and bluetooth. It's on the negative side of a Lynx with a very short wire to the battery nothing in between, all loads on the shunt.

I think the way it's set now it goes to absorb for 15min, then to float at 13.8. the drop you see is the charger shutting off and the battery slowly going to 13.4 where it hits re-bulk (set to 0.4). It's possible that the shunt is still set to about 13.5 as battery voltage, as that's what the manual said. So it's still considering that 100% maybe? I will have to check it next time I'm there.

@Alexandra But this won't destroy anything in a few weeks correct?

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Alexandra ♦ commented · May 30, 2023 at 05:32 PM

@Ivar Eisma

No maybe the graph resolution is the issue and I am overthinking it. Don't stress about it. The MPPT is moving through the three stage cycle and switching off at night, voltages looks good. It looks ok there.

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