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ska avatar image
ska asked

Recover victron battery from overdischarge

We have a Smart LiFePO4 25,6V/200Ah battery connected to a Multiplus Compact 24V/2000VA Inverter.

When i turn the Inverter on, or set it to "charge only", nothing happens. When i then connect it to the mains, the alarm LED comes fully on (not flashing). None of the other LEDs are lit.

Unfourtunately, the battery have been unmanaged for too long, and im afraid it has been discharged below the normal operating voltages.

Is this a correct assumption?


assuming this is the case, and it is still possible to recover it, is the multiplus charger able to recover a battery that has been over-discharged? Or is a 3rd party charger needed?

BR,

Steffen

MultiPlus Quattro Inverter ChargerLithium Battery
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3 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

Use the VictronConnect App to look into the batteries. Make some screenshots of the App.

Do you have any kind of BMS installed?

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ska avatar image ska commented ·
Hi Matthias,

Unfourtunately it doesn't even show up in the Victron bluetooth app anymore. I know the bluetooth is working, as we also have a Victron 12V car charger which shows up fine.

Is there something else wrong then?

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seb71 avatar image seb71 ska commented ·

So do you have a BMS or not?


What is the battery voltage (measured with a multimeter, with nothing connected to the battery)?

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kevgermany avatar image
kevgermany answered ·

One trick I've seen is to connect another battery in parallel. But put a resistor (like a 12V bulb) in between them to stop a large current between the two. Charger sees the voltage from the good battery and kicks in. After a while disconnect the good battery.

Not sure if this will work with the Victron BMS, but worth a try.

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ska avatar image
ska answered ·

So what happened was that we fortunately also had a 24v 'dumb' charger lying around.

So i connected the charger to charge the battery, and i was lucky that it recovered enough so i could remove it, and connect it to the mains charger/inverter again. It started charging with the alarm LED blinking, but it slowly gained a higher voltage. Hopefully it didnt take too much damage..


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