That's 35 amp hrs per 24 hours
17.5 ah from 8pm to 8am
And does not include TV and fan etc...
100 watt hrs over night does not compute anywhere near normal usage
We can't confirm a bad battery until we can verify the usage and the meter install, please give more info about the location of the shunt
And how much power draw it shows when items are being used
Example...I have new AGM batteries
My power meter showed 12.9v at 11:30 pm when I went to bed
At 6:30am (very early for me) It was down 13 percent, battery capacity remaining 87.2 percent
Voltage reading 12.75
Your meter says you used 100 wh , approx 10 percent of what that battery should have when new
Yet your voltage 11.9~12.0v indicates 50 percent charge or less
Flooded cell and AGM do have different voltage curves, but you get the idea, a 10 percent use should have a much higher voltage reading than what you show
A: battery is toast
B: something wrong with meter or installation
C: battery not fully and completely charged before using
This is where the amps function comes in to play
If and when you can see 14.? Volts and only 1 amp or less charging current then the battery is full
A battery still accepting 4 amps at 13.? Volts is not fully charged
Most batteries die from sulfation on the plates, gradually losing capacity from not being completely and fully recharged
I can explain it to you.
But I Can Not understand it for you !
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