Do you desire to know how lengthy your LED flashlight and/or head lamp batteries are going to last? This can be complicated information to discover online. Some carriers list flashlights because that sale and also do not list how long batteries will last in their products. Some other companies the do carry out battery life information do not go into sufficient detail about the operation times of their products.

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As a very general estimate, a low-lumen flashlight (under 50 lumens) will certainly run for around 20-50 hours. A flashlight v 50-150 lumens will certainly run for about 6-12 hrs on it’s highest setting, and also high lumen flashlight or headlamp (over 150 lumens) will certainly run around 2-8 hrs on their greatest settings.

These approximates are an extremely broad, and also your flashlight battery may acquire significantly greater or lower life depending upon the product. below lists several of the components impacting the battery life of LED flashlights and also headlamps.

Flashlight Battery Life

There space multiple points that can influence how lengthy a flashlight’s battery will certainly last, including:

Type the battery (AAA, AA, C, CR123a, D, 18650, etc..) Quality/Material that Battery (Alkaline, NiMH, NiZn, Lithium, Carbon Zinc, Zinc Chloride, etc…)Number of batteries your flashlight hold Brightness of the light (Lumens) Number of irradiate settings on your flashlight, and what setting you usePower attract from the flashlight Battery voltage regulation in the flashlight

provided below are some things that you can look for to help you determine exactly how long her batteries will certainly last.

Power setups (High, Medium, Low, Strobe)

Some flashlights have actually multiple strength settings, and may only display the operation time of their flashlight on the greatest setting. Other flashlightsmay screen the run times because that multiple settings.

For example, the Nitecore MT20A 360 Lumen tactical flashlight pictured to the right has the operation times provided for multiple setups in the description. The product summary states that it has actually 5 brightness levels, and gives the run time for every 5 of those levels, i beg your pardon are:

Turbo: 360 lumens/1 hr 45 minsHigh: 240 lumens/ 2 hr 15 minMid: 120 lumens/ 5 hr 45 minLow: 17 lumens/ 24 hrUltralow: 1 lumen/180 hr

This is really helpful info that numerous flashlight carriers don’t perform on your packaging.

How long will AAA or AA Batteries critical in a LED Flashlight?

Below is a table i created while looking up some different run times because that AA and AAA LED flashlights on Amazon. Together you have the right to see, the operation times vary greatly.

AA and AAA LED Flashlight Batteries will last approximately 1 1/2 hours -7 hours when a flashlight is top top it’s highest setting, and may last because that days if the flashlight is ~ above it’s shortest setting.


It is also important to understand that different batteries have various capacities. Because that example, a AA (Double-A) battery has about 2-3 times the capacity of a AAA (triple-a) battery do of the same material (i.e. Alkaline).

C and D batteries have actually significantly higher capacities than AA or AAA batteries.

Flashlights that host multiple batteries have actually a higher energy capacity than lights that can only host one battery. The much more batteries a flashlight have the right to hold, the higher the capacity should be, and the irradiate will have a higher operation time on average.

There room some flashlights that can use rechargeable batteries. NiMH, 18650, and CR123a batteries are additionally options for part flashlights, and may be able to be used for a higher number that lumens.

Batteries for an Emergency Kit

If you have an emergency kit at home, and you space purchasing a LED Flashlight, headlamp, or batteries for your flashlight, you must consider what type of batteries to purchase.

I recommend having a flashlight that deserve to use disposable batteries due to the fact that you may have a power outage, and also may not have the ability to recharge your device. Also, shot to uncover a LED headlamp and flashlight with a long battery run-time.

Alkaline or Lithium Batteries

If you perform purchase disposable batteries for your flashlight, i recommend one of two people Alkaline or Lithium batteries.

Alkaline batteries are cheaper than Lithium Batteries. Alkaline battery have around a 5-10 year shelf life, and Lithium batteries have about a 15-20 year shelf life. Lithium batteries deserve to handle too much temperatures better than Alkaline.

“Heavy Duty” Zinc Chloride batteries only have a shelf life of around 2-4 years, and have a much lower power capacity than alkaline or lithium batteries.

AA or AAA Batteries

If her flashlight is for an emergency kit, Irecommend to buy a flashlight and/or headlamp that supplies either AA or AAA batteries because you deserve to use these batteries because that a many other devices during an emergency.

If you space buying a flashlight or headlamp for her emergency survival kit, ns recommend purchasing one with multiple power settings. You may want to usage a very low setup during one emergency to conserve light.

For Example, I have actually a many AA and AAA batteries in my emergency supply, yet I don’t have any type of extra CR123A or 18650 battery stashed away. Some flashlights that usage 18650 batteries can also use AAA batteries.

The Streamlight agree Tac 88033 pictured on the right (Amazon Link), uses 2AA batteries, and also displays a operation time of as much as 36 hours on it’s shortest setting.

Tactical Flashlight

You additionally may require a high powered light at time (self defense, signaling someone throughout an emergency, etc…) ns recommend having multiple flashlights/headlamps in her emergency kit, yet if you’re just going to have one, it must be a tactical flashlight through multiple power settings.

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Headlamps are great to have in your emergency kit because that hands-free lighting, and the ones that have the right to hold multiple batteries usually have actually a kind “run time”

The headlamp pictured on the ideal is a 90 Lumen headlamp, and also states that it has a operation time the 8 1/2 hours on the highest setting (there are 3 settings).


Led flashlight and also headlamp battery life different due to all of the reasons provided above. If operation time is crucial to you, carry out as much research as you can around the details product friend would favor to buy, but realize if your is a “run time” listed top top the product, the may not be really helpful when trying to to compare it to another product. You may need to do added research to discover what battery to be used during the test.