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Eric Heiberg avatar image

Maximum SOC dropping by 0,5% every day.

Recently my SOC kept showing less and less (down to 46 % before I partially solved the problem) even though the battery showed 28,2 volts (24 volt lithium Ion battery -Easysolar 3kVA).


I set the charging values on the multiplus lower than the MPPT (since I dont have a bluetooth dongle yet I cant adjust the MPPT charging parameters) after reading about this here on the forum.

The SOC then bounced up to 100% -but the maximum SOC % is slowly going down again by a rate of 0,5% per day:

Now the SOC is showing 97% as todays highest although the battery voltage is the same (28,2 volt).


Any tips on how to solve this?


Eric

Lithium BatteryEasySolar All-in-OnebatterySOCoffgrid
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3 Answers
moonlightrider avatar image
moonlightrider answered ·

I remember I had a similar problem with my little (UPS) setup here


I related this to voltage adjustment to meet battery temperature (sensor), that may cause small ghost loads from time to time... anyway that's what I think, never ever Victron staff gave me a explanation.

The only workaround I came up was correcting (via automatic script in Venus OS, running on Rpi) SOC every day to 100% if system state is in 'Storage'

That script uses dbus to correct SOC on the Multiplus...

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Eric Heiberg avatar image
Eric Heiberg answered ·

Thank you for your answer :-) What do you mean by tweak?

Eric

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change the settings until it works correctly.

What settings do you have now?
increasing the 'charge efficiency' setting is probably the thing you need.

Boekel avatar image
Boekel answered ·

What is the source of this SOC value? (multi, BMV, BMS, ??)

You'll need to tweak the settings of this battery monitor to get the reading correct.

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Multiplus in the Easysolar 3kva is the source -adjusting the charge settings lower partially works.....