3S Battery Okay for DC connection?

Hello! I have a latte panda sigma that I plan on using as a cyber deck sort of thing and I wanted to make it battery powered with a 100Wh battery. I was planning on using a 3S2P 21700 cell 12v battery however I realize that as the battery discharges it starts at 12.6 and then finishes at 11.1 V. Would it still work/be safe if the voltage does drop under 12v when the battery is lower or would i need a converter to keep it exactly at 12V+?

Edit: As alternatives would a 5S1P battery be better suited (only concern being that the max voltage would be 21 going down to around 16 at cutoff) or a bunch of 18650s could get me a 4S2P at 100wh within voltage range at maximum and minimum, it would just be bulkier.