Ultra Stinger Battery

I know that Mag Lite recommends that Mag Rechargeable flashlight users "deep cycle" their flashlights, leaving the light on until the battery is completely dead every so often ... and then recharge from a complete "dead" state.

Supposedly good to extend the life of the battery

What what about the battery in my friend's Ultra Stinger?

Does the same thing apply?

He leaves his Ultra Stinger in the charger, hooked up to his truck ... and says the battery isn't lasting as long as it once did.

Lights only a year old.

Should I tell him to "deep cycle" his battery and try recharging it?

Refer to the ultrastinger manuel on line... www.streamlight.com It says to leave it on the charger for up to a month i believe? It also says that deep cycling is not necessary but in this case... Well I'm not sure.

I replaced the US battery last month that had been in a vehicular charger for about 18 months. It got relatively little use. The battery was totally shot. The charging base for the US contains a LM317 voltage regulator and associated resistors and diodes so assumed that constant charging was OK.

OTOH, My SL20X was used every night on patrol duty and the battery lasted a long time. It's base just had a current limiting high wattage resistor in series with the positive lead. Concerned about the NiCad memory effect, I deep discharged it and this resulted in a bad battery.

Though there is a long standing dispute on the memory effect issue in NiCads, my personal experiences tell me to use them frequently and not to worry about the memory effect. If the flashlight gets infrequent usage, then choose another power source.

Moved to batteries...

--dan