Hey guys, new to the site here. I'm researching electric & hybrid aircraft, and have found answers to almost all of my questions, except for one (so far!). Would removable/swappable batteries (specifically 18650 lithium cell packs) be considered "wet" weight, like the fuel? The aircraft I have in mind will be designed to fly without the supplemental batteries, at the expense of performance & duration, to stay within 254lb. I'm hoping adding more battery capacity/packs would be equivalent to increasing fuel tank size from 1g to 5g (24lb difference in wet weight). Or maybe to word it differently. Lets say one of you guys want to add a 10lb lithium pack to your 254lb ultralight aircraft. Would this disqualify you from FAA Ultralight designation, or be considered "wet" weight? Thanks so much for your help!