DIY Lead-Acid to Lithium-Ion battery conversion 18650

well my favorite battery died on me, so i decided to refit it with old 18650 cells that i have laying around. and now i finally have a use for those old cells too. right now it’s running at 8v and as i add more battery cells i’ll cahnge the voltage to whatever works best. i plan on using a voltage step-up transformer with it to run whatever i need. this Duralast battery was from my greatgrandparents 1981 Mercury Zephyr (witch i got and may convert to electric someday) and its one of the first batteries i r