Newbie 18650 protected vs unprotected

glad you want to learn to be safe
read to get educated
Lithium-ion battery safety 101

ask educated questions after reading

tell us what light you plan to use Unprotected cells in

Determine if the light you want to use Unprotected Cells in, has built in OverDischargeProtection
Determine if the light you want to use Unprotected Cells in, has a built in Battery Level indicator.

stay away from multi battery lights

Keep UnProtected Batteries away from lights with NoBuiltIn OverDischargeProtection

IF you are going to use LiIon, obtain a device capable of telling you the battery voltage, so you can avoid overdischarging.

If you use Turbo, and it stops working, dont turn it on again until you recharge the battery. Do not fire turbo over and over again, that is a good way to get into trouble.

The danger of LiIon is that IF they have been overdischarged, they Might start a fire during recharging.

Put charging batteries in a fireproof location, and do not leave unattended, in case they start to get Hot and Vent with Fire…