LEDs and Batteries

During these short daylight winter days I use flashlights quite a bit, in fact almost every day. The cold weather of winter is hard on batteries. Furthermore, while a small pocket flashlight is a great convince, the battery life, I have found, is not so wonderful. Over the years I have used many compact lights and was never really satisfied with them until the LED (light emitting diode) flashlights arrived. Since the current crop of LED lights, by in large, use the smaller AAA or AA batteries I wondered which was the more economical. That was not hard to figure out. Web sources show that an alkaline triple-A battery has an energy capacity of about 1150 Mah (Milli-amp hours) while the double-A batteries have around 2850 Mah. There is not much to debate about here. The double-A battery has almost two and a half times more energy than the triple-A cells. While the energy is much greater for the double-A battery the cost is about equal, or sometimes even less. Needless to say, I purchased a LED light that uses double-A batteries - actually one that uses a single double-A battery. You might think that a single battery light would be dim but LED’s are very different light sources. Led bulbs use around 3% - 5% of the energy to provide the same amount of light as the incandescent lights, which produce more heat than light. LED lights produce almost all light and very little heat. Furthermore the LED light bulbs generally last much longer than the filaments of the incandescent bulbs and can be purchased with a 1.5-volt bulb grouping that is as bright, or brighter as a 3 volt or 4.5 volt bulb grouping.
These are amazing, energy efficient compact lights but don’t over power them! A slight voltage increase, over the designated voltage, will easily ruin a LED bulb - they are very sensitive to over-voltage so don’t try to get more output by hooking a 1.5 volt LED to a 3 volt supply - you will only fry the LED.
Finally, some people do not like the LED’s bluish light cast but they are increasingly developing whiter light as LED technology improves. I find them to produce less harsh shadows than my old Maglight, possibly because the light source comes from several bulbs. This improves my vision in the dark. LED lights are definitely a landmark item for people who live in the country and use a flashlight often.