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sedge avatar image
sedge asked

Lifep04 idle charge

Hi

Newbie question .

I have a 100ah 12v lithium battery to run a fridge in the back of my car. It is used infrequently and taken out of the car when not in use. It can charge in the car with a DC-DC charger and I have a 15A Victron Blue smart charger at home.

I’ve read that lithium batteries, including LFP, last longer if stored and about 50% charge.

Does the charger/app have a profile to keep the battery at, say, 60-70% while not being used, then change the profile to full charge a day or two before being used?

Is that something that is practical or desirable?

Thanks

Steve

battery charging
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1 Answer
Alistair Warburton avatar image
Alistair Warburton answered ·

I have Ultramax batteries connected to a 24V Multi...

I previously had a single Ultramax LiFePO4 connected to a no name inverter operating as a UPS for fridges.

I asked Ultramax what they recomended and they said that with an apropriate 'float' voltge the internal BMS would handle the battery and that 24/7 float was not a problem.

I am not 100% sure but I 'think' the internal BMS needs some headroom to work when ballancing and that continually cycling within a small partially charged range could cause issues. (Just a theory, that)

I havent seen an issues floating a battery of this type for a couple of years.

If you are talking about raw cells then I suspect you would need to look to the BMS you install for answers.

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