Are these batteries still good?

[Bronco]

I have four AccuPower Digital Power 6000mAh C-cell NiMH batteries that I purchased new about 8 months ago in anticipation of receiving a new flashlight. The delivery of the flashlight has been delayed since, but I may be receiving it in the next month or so. My question is whether or not these batteries, which haven't even been taken out of the original packaging, are still any good. Are there shelf life issues with NiMH if they haven't been used at all?

If the answer is "maybe", is there any way I can test them at home? The only gear I have that might be useful in determining the health of the batteries is a new Powerex MH-C808M charger (also unused) and a Fluke 179 digital multimeter.

 

[Raymond]

Your charger would work fine to test, charge and -if necessary- revive the batteries.
Don't worry too much about the batteries. 6 months is not long enough to cause damage, imho. Maybe they need to cycle a bit to get to their full capacity, but your charger can do that automatically.

 

[Bronco]

Thanks for the response, Raymond. The batteries have actually been sitting around at my house for at least 8 months, and who knows how long they were on the shelf at Thomas Dist. before that. But it's good to know that my charger will be able to help sort it all out. Thanks for the info.

 

[darkzero]

I've got 6 Titanium 4500mah C-cell NiMhs. They sat for a little over a year without being used. One of them doesn't charge on my old Vanson charger anymore. The other 5 still work fine though.

 

[45/70]

I've got 6 Titanium 4500mah C-cell NiMhs. They sat for a little over a year without being used. One of them doesn't charge on my old Vanson charger anymore. The other 5 still work fine though.

I'm full of ideas today Dark! You might try setting one of the good cells on a metal strip negative side down, for instance, the stainless steel edge around your kitchen sink. Put the "dead" cell right next to it, on the strip. Take a table knife and place it across both positive terminals for, say 20 seconds. Then see if the dead cell will charge. You may have to repeat the "kitchen process" a couple times to see if it works.

What's happening when you do this, is the good cell is paralleling with the bad cell, and giving it enough of a boost to get it's voltage up enough that the Vanson recognizes the cell.

Good luck!

Dave

EDIT: Don't try this with Li-Ion cells!!!!! Things could get really exciting!

 

[darkzero]

I'm full of ideas today Dark! You might try setting one of the good cells on a metal strip negative side down, for instance, the stainless steel edge around your kitchen sink. Put the "dead" cell right next to it, on the strip. Take a table knife and place it across both positive terminals for, say 20 seconds. Then see if the dead cell will charge. You may have to repeat the "kitchen process" a couple times to see if it works.

What's happening when you do this, is the good cell is paralleling with the bad cell, and giving it enough of a boost to get it's voltage up enough that the Vanson recognizes the cell.

Good luck!

Dave

EDIT: Don't try this with Li-Ion cells!!!!! Things could get really exciting!

What a good day, full of ideas & I'm glad! Your trick worked! I placed the dead cell & a fully charged cell on a stainless steel ruler. Then I connected both positive ends with a piece of metal & counted to ten. Then I did another ten count.

Before the cell measured a steady 1.1mv. After your trick it measured 1.0v. I threw it on the charger & it is now charging beautifully! They're old cells & I know they're high capacity cells now but I'm glad I was able to save the cell & put it to use again.

Thank you very much Dave! :twothumbs

-Will-

P.S. - Good thing you mentioned not to do with Li-Ions. I probably would have tried it one day. :laughing:

P.P.S. - Sorry to hijack your thread Bronco. Well if one of your cells don't charge, try 45/70's trick, it worked for me.

 

[Bronco]

No sweat, Will. We're all learning here.