Tuesday, November 30, 2010

CR123A or AA?

For the average person, a flashlight is a flashlight, as long as it's adequately small and bright. A large percentage of people don't know or care about different bulbs, diodes, lighting modes or battery types. They never really had to know, because they don't normally use flashlights.

Which battery: CR123A - Lithium or AA - Alkaline?
For us, it's different. We care about brightnesses, runtimes, lighting modes, flashlight size/weight, etc. All of this matters because we care about pushing flashlights to the limits: getting the brightest light, with the longest runtime in the smallest package.

In the pursuit of flashlight efficiency, one thing cannot be overlooked: The choice of battery. For the past 40-50 years, alkaline batteries have been the standard for a quality battery.

Within the past few decades, as technology has advanced, the lithium battery was introduced. Lithium batteries have a longer life for high-demand appliances and can even offer higher voltages than your standard alkaline battery, although they are generally more expensive.

This leads us to title of this post, "CR123A or AA?". For those who do not know, CR123A are popular lithium-cell batteries often used in flashlights. I wanted to give you some advantages and disadvantages, comparing the lithium-cell CR123A battery with the alkaline AA battery, both common in today's flashlights.

AA - Alkaline Cell

Never fear, excellent flashlights that use
AA batteries do exist, such as this
Quark Tactical QTA by FOURSEVENS.
The alkaline AA battery has been around for many many years. It is so common, that it can be found almost anywhere. This commonality is it's greatest strength and the main reason why so many flashlights use it. It is an adequate performer, especially for items that drain the battery slowly.

High load applications are where the alkaline battery falls short, being the main reason why it is not as good for flashlights as a lithium cell. A AA battery, when used in a powerful flashlight, has about 700 mAh (miliampere-hours: a unit of power), which corresponds to how long of a runtime the flashlight can have. When you read about CR123A batteries, you will see how many mAh the lithium-cell battery can have.

Alkaline AA batteries are also heavier than lithium cells, the average weight a AA alkaline battery being around 0.9 oz. The dimensions of a AA battery also dictates the dimensions of the flashlight. A AA battery is 2.0" longer with a diameter of 0.5". Knowing this, a flashlight that uses such a battery cannot be smaller than that. Flashlights that use AA batteries are generally longer and more slender than flashlights that use CR123A batteries.

CR123A - Lithium Cell

The FOURSEVENS Quark Pro QP2L is a high quality
flashlight that uses CR123A lithium cells.
The CR123A is quickly becoming a more and more popular flashlight battery. Although not common enough to be found in all local grocery stores, the slight difficulty in finding batteries may be offset by this battery's excellent performance.

Like I mentioned before, this is a lithium-celled battery. The fact that it uses a different chemical makeup than an alkaline cell means that it can offer higher voltages. The CR123A battery outputs 3.0V as opposed to 1.5V in a AA alkaline battery. A higher voltage can mean that the flashlight using it is capable of being brighter.

The CR123A battery is also a better performer in terms of capacity. The CR123A battery has about 1500 mAh (double that of a AA alkaline battery), which means that the flashlight that uses it generally has a longer runtime.

To top it off, CR123A batteries weight 0.6 oz, 33% lighter than alkaline AA batteries. A CR123A battery is 1.3" long with a diameter of 0.6". Flashlights that use CR123A batteries are generally shorter and wider.

Conclusion

Personally, I am a big fan of the CR123A battery. Flashlights that use them are generally more powerful and have longer runtimes. Sometimes, however a flashlight that uses AA batteries may be the better choice. The only situation that I can think of that you might want a AA-powered flashlight instead would be for people who do not have easy access to CR123A batteries.

In the future, I predict CR123A to continue to grow in popularity, inevitably leading to CR123A batteries being easier to find and purchase. The future, of battery technology resides in lithium cells. As technology becomes better, look forward to flashlights being less expensive, along with having longer runtimes and brighter outputs, eventually leading to the complete phasing out of alkaline batteries altogether. It's a bright future indeed.

5 comments:

  1. Only problem with CR123A batteries for me are the expensive price. At nearly $2 for a single battery it's pretty pricey. Another choice that could maybe be touched on is the use of re-chargeable batteries. I have purchased Re-Chargeable AA batteries that are 2100 MAH and AAA batteries that are 1000 MAH each. Which I use in my everyday flashlight. Just another thought for people who are looking for longer lasting batteries. Have a good day, http://marcos2178.blogspot.com/

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    1. The voltage is what makes the big difference. AA=1.5, cr123a=3.
      1500mah@3v/1Hr=4.5 watts
      2100mah@1.5v/1Hr.=3.15 watts
      42% increase in power.

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  2. This comment has been removed by the author.

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  3. Marcos, the MAH of your standard NIMH rechargable AA battery is actually lower than that of a standard CR123. A not so known fact is that for both of those types of batteries, the max mah actually varies wildly based on the load being put on the actual battery. For example, a standard Alkaline AA can approach a max capacity of 2900mah with some brands, however this would be in best case scenarios such as a device that does not pull current fast like a remote control. For a situation like you have with high current flashlights, it is as the author said. You may be lucky to get 700mah with that alkaline or NIMH battery, less so out of the NIMH. I can however definitely recommend rechargeable CR123 batteries. They can be had for cheap on the internet. I personally use a trick which is to buy cr223 batteries and cut them open removing the two linked cr123 batteries inside. These can be even cheaper and I have bought them on sale for $1 a piece before, so that is basically 50 cents each. This being said you are actually getting more battery for your buck anyways as a CR123 has twice the voltage and a much higher MAH, the higher voltage also means longer usable battery life as you incur voltage drop. All in all, this means you can sometimes get even better deals on CR123's than AA's! Good luck and happy flashlighting!

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  4. alkaline batteries drop down on capacity drastically when used in cold weather/low temperatures, even -5C combined with high current consumption will decrease the capacity to 1/2~1/3 capacity on alkaline battery

    lithium cells are rated -20C without capacity drop, and they're created for high current consumption to begin with

    another thing is lithium cells are rated to hold charge for 20 years, alkaline cells barely reach 2 years without drastic capacity drop

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