I could be wrong,not being that much of an electrical technician.....but you have a 12V. 100 watt input,need a fair amount of output,plus some power loss through that inverter. Doesn’t seem to add up to me for anything other than very short term usage. Then there’s the consideration of whether or not you can depend on the sunshine.
12v 100 watt panel will give about 8 amps if my math is correct. So if I have a 200 amp hour battery, not going over 5% of the charge would be about 10 amps, correct?