Hello,
I am using a Zero2Go Omini power supply as a UPS for a Raspberry Pi 4b.
A 3.7V Li-Po battery is connected to input channel b, and input channel c is connected to a 12V power supply.
The Li-Po battery serves as a backup battery for UPS mode.
Low voltage threshold = 3.2V, recovery voltage threshold = 4.2V, step-down engine is always on.
Although the low voltage threshold is 3.2V, the UPS shuts down the Raspi at approx. 3.8V.
How can this problem be solved?
It is possible that your Li-Po battery's voltage dropped too much in a very short moment, which triggered the shutdown, while the actual voltage was not recorded in log.
It is most probably the case, if you see the measured battery voltage is correct on the console.
My suggestion is to test it with an adjustable power supply instead of using a real 3.7V Li-Po battery. The power supply should be able to output at least 3A current.
If a good power supply can avoid this issue, you may source a better battery.