Introduction

If you have an x-cell Mag-Lite flashlight lying around, and you don't use it accept for emergencies, you know that you frequently find them with dead batteries when you need them the most, and how much of use is that?  Batteries can go dead even when they are not in use, so how can you save money?  Rechargeable flashlights with chargers can cost $90+ which is expensive compared to a regular Mag-Lite 6-Cell costing about $30-$35.

Using Ni-CAD Batteries

The simple answer is using Ni-CAD rechargeable batteries in your regular flashlights.  The only problem with that is rechargeable batteries only carry 1.2v each compared to 1.5v for regular Alkaline batteries.  The solution to that problem is to change the bulb of the flashlight to a lower-voltage bulb.  The general rule of thumb for converting your flashlight is if you have a 6-cell, use a 5-cell bulb.  If you have a 5-cell, use a 4-cell bulb, and so on.  That way, it will be just as bright.  Also, make it a habit of charging your batteries in all your flashlights around the house about once a month, and you should be good to go the next time you need it.

Why Not Ni-MH?

Nickel-Metal Hydride batteries is not a good idea because they can go dead in about a week of shelf time, and nobody wants to worry about charging their batteries once a week.  That's worse than using regular batteries.  Plus, Ni-CAD batteries are cheaper.