Default absorption time not enough (winter camping)?

Q&A and troubleshooting
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1

Hi there,

I’ve got a Winston Lifeypo4 battery in my camper, and two MPPT 100/50 chargers.
I noticed, that now in winter, the battery doesn’t get fully charged during a day, because the MPPTs switch to Float although there would be enough sun.

Right now I’ve got the standard settings for Lifepo (although this might not be ideal for Winston/Lifeypo4).

Is this caused by the default maximum absorption time of 2 hours?
Or is there any kind of reset if the battery is not fully charged, and it starts a new cycle?
In this scenario, winter and low sun, should I switch to the adaptive mode?

2

Pls post some screenshots of your settings, the battery size and your installed solar wattage.

And ofc your use.

Do you have a smartshunt installed ?

3

@Ludo at the moment it’s only a 60AH 12V Winston Lifeypo4 battery.
I’m building a 300Ah one currently.

I’ve got dual 450W Panels, with a 100/50 smart solar each.
I also have a smart shunt. All of them are in a network.

The use is a camper, so I’m wondering, if in winter there is not too much solar energy, and it
charges only slow - if the absorption time is limited to 2 hours, it will never get full?

4

Need your settings of mppt and shunt…

5

Sorry, forgot to add it, those are the last ones I have tried:

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This is what the SOC looks like during daytime:

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As you can see, it charges from 43 to 56% in 2 hours - I’m not sure how this relates to bulk mode, I thought only absorption is limited…

This is the voltage:

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6

I’ve set my float voltage to 13.9, in this way the SoC comes down only 1% as long as the sun shines.

7

So the actual problem seems to be that it’s leaving bulk too soon.
Unfortunately, I have no readout for the charging status, so I have to watch closely on my phone.

I also read that a smart battery sense might help as the MPPT could read the voltage wrong - although it’s only around 1m cable.