Anyone? . . . + terminal -, - terminal +?

[Orion]

Last night, I was checking the batteries in my 6 C 5 watt LED flashlight because the output was poor. I checked the voltage on each, but one of them had a backwards response. I turned the battery around and touched the leads [+ battery terminal to - voltmeter and vice versa] and it showed about a .5 volt to the positive. later, when I touched the terminals the correct way, it showed hardly any volts, just barely moved the needle the wrong way.

Anyone ever experience that phenomenon before? /ubbthreads/images/graemlins/confused.gif

 

[earl]

This is what is called a reversed cell. When you discharge a series of cells, the current flows through the whole series. If one cell dies before the other, it will still have the current flowing through it causing it to become reverse charged. This is why you should use matched cells. Much more important in NI-CAD's. That is why they say not to discharge completely. One cell has to be first, and it will get reversed.

 

[Orion]

Does that eventually cause a rupture? You know, like when you open a flashlight and it's all corroded inside?

I guess one would be well advised to take the batteries out and check them from time to time. /ubbthreads/images/graemlins/faint.gif

 

[**DONOTDELETE**]

you may be able to fix that cell with a 24 hour charge that keeps it warm, not hot..

 

[Orion]

I guess I should state that this was an alkaline battery.

 

[**DONOTDELETE**]

nevermind.

--Emily