PSA, for people interested in using LiIon in the SC53c N. (corrections and additional info welcome):
Zebralight deleted LVP from the driver, to make room for more mode groups, and officially the light is not LiIon compatible.
USB Rechargeable Protected 14500 LiIon from Lumintop, fit and work in SC53c N.
Some people use Unprotected LiIon, responsibly. Their brain is the LVP.. They monitor battery voltage, and recharge before the battery gets too low.
When going from 14500 LiIon, back to AA, remove the LiIon and Press the Switch for a moment, while the light has no battery inside, before inserting the AA battery.
This resets the battery meter so it works w AA Voltage after using LiIon..