1.) How does ACPI work in this environment?
My initial instinct is that "it doesnt".
I believe ACPI is a PC BIOS/Motherboard thing, the interfaces between battery and laptop is more advanced that a simple usb-charger port which is what the Pi have.
Edit: I don't know what extra circuitry is added by the "pi-top" that might be used for monitoring battery levels, but I have a feeling their support forum might be a better place to ask this question.
I have figured out how to manage the power, I can monitor it, I can shut it down etc, which is why i came to this forum and not Pi-Top. Pi-Top will tell me to run Pi-Top OS and not the standard runoff the mill Raspbian Jessie with pixel. I know the pi does not contain ACPI in a "traditional" BOIS nor has the hardware to do this. I want to know how do I implement this in the OS, even if I have to "fake it".
If Raspbian does not support ACPI then why is there a Battery Monitor LXPanel Applet build into the standard distro that says "Display battery status using ACPI".
From what I understand there needs to be "/proc/acpi/battery" and some file containing specific data and the battery monitor applet will work. But I have been unable to find any documentation relating to this. So my best guess is that either Raspbian supports this, and one one knows how to use it. Or the battery monitor applet is completely useless and should not be in the distro as it's misleading people. I'm not sure which is the case.