What's the best way to treat batteries?
NiCd + NiMh ask for a full discharge before re-charge due to the otherwise occuring memory effect that will reduce capacity significantly. To avoid the need to run with an almost empty battery that doesn't provide sufficent power for a use case for long, best is to use a charger that automatically is discharging a non-fully-discharged NiCd/NiMh battery before charging.
Li-ION + Similars as for never full discharge and never 100% charge while they are
software managed in EACH and EVERY case and that sofware when it shows you 100% charge in fact it's within the safe limits, which again in fact means that you can (fake) fully discharge because it will switch off way before the real zero is reached and (fake) full charge before it wil slow down and ultimately stop charging way before (real) full charge is reached.
lead batteries (cars, motorbikes starterbatteries etc.) are best just kept as fully charged as possible.
they last the longest when they never fully (deep) discharge and are kept as close to 100% as possible because the process of charging ultimately "verschlammt" no clue whether the direct translation would mean the same LOL. further very low but steady currents are healthiest for those.
need more, ask more, but those are the actually most used kind of batteries.
charging Li-IONs with brute force (non-software-managed) is illegal in most countries because an uncontrolled charge of such a batterie makes it more of a bomb than an energy reservoir which is why there are strict regulations "TÜV" for example as well as there is no such a thing like a brut force charged Li-ION battery pack. this just in additon to the above mentioned for better understanding