This got me thinking...

[UFO]

On my last thread, I asked about "Single Cell 123A" Flashlights. I received a variety of really good information. One post in particular got me thinking. I was informed that some of the newer "Single Cell" 123 designs would only accept rechargeable 123's. That got me thinking. Therefore, I have two questions please:

1. What would happen if I stuck a Non-Rechargeable 123 in a light that only accepts rechargeable 123's? Would it simply not work or would something bad happen?

2. Have you ever had so many flashlights that you forgot what lights will accept which batteries?

 

[ledbetter]

Bottom line is you must match the voltage range or limitations of your light with the batteries you use. Generally, 123s are 3v and rcr and 16340 are 3.7. Read the fine print and never exceed the voltage limits of your light.

 

[LED Monkey]

It would probably still work but the light would not be as bright due to the lower voltage. I don't believe anything "bad" would happen. The light was designed to run on a higher voltage of the rechargeable battery. Now if it was the other way around and it was designed to run on the lower voltage (3v.) of the non rechargeable and you put in a higher li-ion @ full charge (4.2v) it could damage the light.

 

[archimedes]

Moved this to "Flashlight Electronics" because it depends on the specific driver.

There are certain types of drivers that may attempt to pull too much current from the (lower voltage) primary, which could create a safety hazard.

 

[Lynx_Arc]

One other thing to consider is some lights designed for lithium rechargeables have low voltage cutoff and a CR123 primary could be near or below the threshold such that if you can get it to work it may shut off after a short while or on a higher drain mode shut off quickly.
Basically it is best if you are buying a light to research the batteries it uses and if it doesn't list a battery you are interested in using take that as a default that using that battery is a risk until you can verify it for sure. There are some lights that use primaries that people say they got it to work with lithium ion but that doesn't mean that it isn't overdriving it hard enough to fail in the near future and since lights differ a little and rechargables differ some too YMMV.

 

[sween1911]

What Lynx_Arc said. I ran into this when crafting a module for someone that wanted to use primary CR123's in a light with a driver optimized for RCR123/16340's. Due to the low-voltage warning, it will begin to blink or cutoff entirely. I had to use a 2AA driver optimized for 3 volts and not 3.7-4.2v.

 

[jon_slider]

I was informed that some of the newer "Single Cell" 123 designs would only accept rechargeable 123's.
...

1. What would happen if I stuck a Non-Rechargeable 123 in a light that only accepts rechargeable 123's? Would it simply not work or would something bad happen?

2. Have you ever had so many flashlights that you forgot what lights will accept which batteries?

Anduril lights have vastly more features and power than a basic two mode low cri light
so if you put a CR123 in it, the light thinks the voltage is too low and will indicate by flashing, that the battery needs replacing

I do not own any lights that Only use CR123. The CR123 lights I own work with both Primary and Rechargeable. IF you put a rechargeable in one of those old designs, it can kill the driver.

so the problem is not lights that only use rechargeable, or use both, the problem is with lights that ONLY work with Primaries.

I just ordered my first Anduril light, a Lumintop FWAA. This will be the only light I own that uses LiIon only.. I dont mind, since I only use Rechargeable batteries.