Dropped / Damaged Battery

Ok, I searched and didn't find an answer which actually surprised me.

I dropped one of my Eneloops today and the plastic wrapping came off a little right around the edge. It looks like a bit of the side of the battery is exposed so I'm concerned about that coming into contact with other objects. It also looks like it might be slightly bent down where it was impacted.



Should I write this off as toast? Or should I put a piece of shrink wrap on it to cover the damage and keep using it?

Hello Matt,

Nail polish works great.

Mark the cell and watch it. If it works just like it did before, use it. However, if you see some voltage jumping around, the separator could be damaged and in that case you need to recycle the cell.

Tom

Thanks Tom,

My biggest concern was having the side come into contact with something and short out. Not sure if that could happen or not. I don't have any nail polish but do have New Skin (used in bowling), which is basically the same thing. I will also check the voltage on it from time to time.

I also managed to somehow damage a Duraloop...it has an indentation on the bottom that looks suspiciously like the + end of another Duraloop (circular scratch is from tailcap spring). The battery seems to work fine, but it just looks funny. If that one is put in first, the total length will be a little shorter. Wonder if there's anything to beware about?

I have 2 pairs of eneloops dented like that. Happened when I dropped my Fenix L2D with them in it. Both pairs seem fine without a change in behaviour, but do check the cell capacity just incase.

http://www.eneloop.info/home/faq.html

See question 15.

It doesn't say what the "damage" might be, exactly, but there can be some internal damage to NiMH cells caused by mechanical shock.

As I understand it, the separator in MiMH cells is very fragile, compared to NiCd cells anyway. This is why you don't want to drop cells. I remember somebody saying that if you drop a cell from more than three feet onto a hard surface, you should recycle it. Heck, I drop 'em all the time! Well, not really, but I've never noticed a problem, and I've dropped them from more than three feet.

If you drop a NiMH cell, and then notice it doesn't hold a charge well anymore, then that'd probably be a sure sign that the separator was damaged from the fall. I don't think this really happens very often though.

Dave

Robin24k said:

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Off topic: Your battery labels (3 & 7) look really nice. How do you do it?

45/70 said:

I remember somebody saying that if you drop a cell from more than three feet onto a hard surface, you should recycle it. Heck, I drop 'em all the time! Well, not really, but I've never noticed a problem, and I've dropped them from more than three feet.

Click to expand...

Wonder if that applies to cells in a flashlight? The flashlight ought to take some of the shock, but it's not like the cells are bubble-wrapped inside...

OpenGuy said:

Off topic: Your battery labels (3 & 7) look really nice. How do you do it?

Click to expand...

Thanks! Brother P-Touch Labeler.

http://www.brother-usa.com/Ptouch/ModelDetail.aspx?ProductID=PT2700

A have some NiMH that were in a toy that fell out my upstairs bedroom window... that's quite a fall to the paving slabs of the patio below. Toy was a write off but the batteries have been working for a year since so I'd say they're not terribly fragile.