Noob with questions about battery etiquette

[The Jinx]

Hi,

After my introduction to the KPR112 + 3x123 mod I've become hooked on flashlights. So after the modding my first flashlight I was left with an extra Duracell Ultra Photo CR123A battery and decided to mod another one of my cheap flashlights. I went out to purchase some extra CR123A batteries but noticed while shopping that the Surefire 123 was significantly cheaper than my Duracell CR123A that was left over from my first flashlight mod. My question is basically:

Is it safe to use 1 Duracell CR123A battery along side with 2 Surefire 123 batteries? I more so worried about the possibility that there might be different chemical makeup between the two different types/brands of batteries that might react with one another.

On another note, I've found some older CR123A from my sister's older cameras and while using a multimeter noticed that the voltage output of three CR123A in series was 8.78v and when i was trying to use it in conjunction with the KPR112 light bulb, it would shine for about a second and then die out. The light bulb worked with moderately fresh batteries but I was wondering why a 6v bulb wouldn't stay lit up with 8.78v.

Thanks,
Jinx

 

[DM51]

Welcome to CPF, Jinx

It is a very bad idea to mix cells that are of different brands, ages or states of charge. One will always discharge more quickly that the other; this can then lead to it being "reverse-charged", whereupon it will become extremely hot and possibly explode.

I'll move your thread to our Batteries section here, where you will find plenty of advice on purchasing and using cells. You'll also see a "Smoke & Fire" sub-forum there, which contains a few horror-stories that arose when people failed to take adequate safety precautions.

 

[alpg88]

The light bulb worked with moderately fresh batteries but I was wondering why a 6v bulb wouldn't stay lit up with 8.78v.

Thanks,
Jinx

you already got an answer about mixing batteries. now next answer is

you measured no load voltage, which doesn't say much, at least in those types of batteries, once you hooked the load to it they dropped voltage to the point where it was too low for bulb to stay lit.

 

[LuxLuthor]

Jinx, it is great that you asked the question before acting. Very wise step. DM51 has answered, but you may find this other thread a couple weeks ago on the same topic useful.

:welcome:

 

[DM51]

^ That is a very good and useful thread linked by LuxLuthor. It gives an excellent and very detailed explanation about the dangers of mixing unmatched cells.