lol no, they are made to house 18650 or 21700 cells in those sections, how much research have u done? how did u not know most people use pelican box (or similar product) for their top mount box
based on the deck you posted I assumed that this is the type of battery you had. that deck is flexible so you’d need a flexible segmented battery if you are undermounting it.
@zZoKo the reason this is the case is that it seems like half the stuff you say consists of completely uninformed nonsense. It’s generally easy to prove you wrong, because many of the misgivings you have could easily be rectified by just reading this forum a bit, and so to people who have done this, its simple to correct you. Most of the time, its glaringly obvious that you are don’t really have a clue what you’re talking about, and yet you seem to have the impression that you do. And just as @ShutterShock said it’s super aggravating to witness.
Maybe you don’t think you need a proper battery pack, but i think its fair to say you definitely do need to spend some time educating yourself.
Also @frame don’t know for sure if this is the case, but i think its possible he thought the liion packs like the one you showed were lipo since he couldn’t see the individual cells under the shrink wrap (LMAO) Or maybe he though the only way to connect cylindrical cells was in the brick format like his flat pack, and so when he saw the split pack he assumed they must be lipos (even more LMAO)