Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: HDL_CinC_Dragon on January 03, 2008, 08:29:09 PM
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I have here a AA alkaline battery that I tested with my DMM and its running .050v in the wrong direction lol I put GND to negative and Pos to Pos and my DMM reads -.050 when set on 2VDC setting. I tested other batteries and theyre coming out normal. Anyone ever hear of something like that? Or know why it happens?
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Hi
I know with Nicads if the cells are discharged unevenly it can happen(example if there are 3cells and only one is discharged/damaged the other two can push current through the discharged cell thereby reverse polarizing it.
Also lead acids can be reversed polarized (can be dangerous) just by changing the direction when charging. As the lead and lead oxide plates both react with the sulfuric acid.
For alkaline I vaguely remember hearing that if the internal barrier has flaws you can end up with reverse polarity
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try and do it again see what happens
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try and do it again see what happens
do what? test it? I just did as well as 3 other batteries. The 3 batteries I know to be normal came out normal and the 1 battery I know to be reversing polarity was still giving me a negative .050v reading.
For alkaline I vaguely remember hearing that if the internal barrier has flaws you can end up with reverse polarity
Makes sense to me, ill go with that :P
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Thats what happens when you use alkalines ;)
(the baby squirrels are crying, cause now you gotta throw it away)
More seriously now, I suspect there was a flaw in the battery . . . something inside 'broke' . . . Possibly a manufacturing flaw, or damage from something . . .