It’s not necessary for lights with internal low voltage protection built in driver which will not allow complete depletion of battery. For lights without this feature protected batteries are necessary for your own safety. In general ICR li-ions are more volatile than IMR batteries.
Read this: BU-205: Types of Lithium-ion - Battery University
Before you decide on purchasing any li-ions make sure you read and understand safety hazards, see here:
” Lithium-ion battery safety 101”:Lithium-ion battery safety 101