From the main battery terminals, as far as I understand. I appreciate that this relies on the path from the DC-DC converter to the 12V battery to be sufficient for 80A sustained. Apparently this is fine, but I have yet to look myself.
An ICE car can have the battery supply ~200A through that cabling, though of course that's burst and not sustained. But it does suggest to me that it's not out of the question - especially as it's normal in the automotive industry for some cabling to carry such high currents for this reason.
An ICE car can have the battery supply ~200A through that cabling, though of course that's burst and not sustained. But it does suggest to me that it's not out of the question - especially as it's normal in the automotive industry for some cabling to carry such high currents for this reason.