When you’re on an extended trip in the backcountry or facing an emergency, rationing becomes an essential survival practice. This means rationing food, water and even the battery life on your LED flashlight. Without the ability to carefully control and monitor how much precious light you’re using, you could end up in the dark before help – or the next town on your journey – arrives.
Battery life, also known as run time, can vary widely between LED flashlight models. Thanks to the relatively new ANSI FL1 flashlight standards, many manufacturers now use standardized testing methods to accurately determine the run times of their LED flashlights. However, there are other factors – some external – that can influence an LED flashlight’s battery life. It’s important to consider these conditions when you’re in a situation that requires careful rationing of your resources.
Brightness setting. If your LED flashlight has multiple brightness settings, you should always be conscientious about the setting you’re using, particularly if you need to conserve battery life. In general, flashlight manufacturer’s measure run time based on an LED flashlight’s highest setting; thus, by using a dimmer beam you can typically extend the battery life well beyond the reported run time. However, this isn’t always the case – and when your survival may be on the line, you can’t necessarily afford to make assumptions.
Weather. Believe it or not, the weather can also have an impact on the battery life of your LED flashlight. Prolonged exposure to very hot or cold temperatures, high humidity and rapid changes in temperature can all interfere with your batteries’ efficiency and cut your flashlight’s run time short. In extreme cases, batteries can even simply stop working. While you can’t control the effect weather has on your LED flashlight, you can help alleviate the problem by keeping your batteries insulated and factoring the temperature into your rationing.
Battery size. Keep an eye out for LED flashlights that advertise a long run time but require a lot of batteries. The reason is simple: You are paying for that extra battery life. A higher-quality, more efficient flashlight will not necessarily need a lot of batteries. When shopping for LED flashlights, do a cost factor analysis and decide if you are willing to pay more in batteries for an extended run time (it may be worthwhile if you do a lot of backpacking). Weight is another consideration; the fewer the batteries, the lighter the flashlight is.