Hello fellow inspectors,
The Stinger batteries are Ni-Cd (Nickel-Cadmium) type which traditionally have a condition called a "memory effect" dependant on the depth of the previous discharge. Repeated shallow discharge use results in shallow capability, or in other words short term light availability. To maximize it's ability, use it until the light starts to dim (deep discharging), as mentioned by a fellow inspector. Repeated deep discharging can start to bring back it's full capability, not guaranteed of course. Ni-Cd have only fair charge retention, so keeping it fully charged becomes important. Ni-Cd's have good cycle life when used and charged properly. As usual beware of cheap knock-offs.

Just trying to add a few cents to the wealth of information given here. Keep up the good work.

Richard Hamann
S & R Inspections
Brookfield, Wisconsin.