Dropped 18650 - Keep or Discard?

Last night, I went for my usual nighttime hike. It was quite chilly on my hike, and my hands were cold to the point that they didn’t work too well. So when it came time to swap batteries, I fumbled my Samsung 35E and dropped it to the ground. Unfortunately, the trail was rather rocky at that point, so the cell had a rough landing from a height of about 3-3.5ft. The wrapper is somewhat nicked. But as far as I can feel (with warm hands, that is), the can doesn’t seem to be dented.

When I got back home, I tested the cells some more. I drained both of my 35E’s to around 3.15V in my SC600w II and recharged them. I don’t have an analyzing charger - my VC4 is as close as I have. With that charger, the undropped 35E accepted 3197mAH, and the dropped 35E accepted 3226mAH. So charge acceptance appears to be fine with the dropped cell. Both cells charged to 4.18V (both measured after a few minutes of resting). It would appear that the cell is OKAY, at least at the time. But is a dropped cell dangerous? May it cause problems down the road, making replacement the best option? Or should I simply rewrap it (or maybe even not, since it represents nomshort circuit risk) and continue to use it? The cells are only a week old from Illumination Supply.

I would keep.

I’m sure its fine. If the insulation of the wrapper is compromised and makes you nervous you can always rewrap it.

If the wrapper is nicked id rewrap and keep. Ive dropped a handful of cells on ceramic tile and never had a problem.

As a precaution I always discard any damaged battery, but in this case i would keep.

Dropped many cells over the years, never had to throw out and never had an issue. As said re-wrap if required and just keep an eye on it at 1st when charging…………all should be fine imo.

I’d keep it because it’s not dented. As far as the nicks in the insulation on a non-protected battery, I wouldn’t worry about that because the body of the battery, except for the tip, is negative just like most flashlight tubes. That said, unless you have a flashlight that the battery is inserted with the positive end towards the tail cap, I think it’s a non-issue

Many of my batteries are like this. Some older cells have been dropped so many times they have to be reshaped to be able to still slide into the battery tube, maybe there is a minuscule capacity loss but definitely usable.

If the tension spring on your charger hasn’t accidentally slung a cell across the room when taking the cell out of the charger then you’re not a flashaholic, lol. :wink:

I’ve had 2 18650 cells that totally stopped working after i dropped them on a concrete floor.
Others have survived just fine though.

Were they protected or non-protected? Maybe you damaged the protection circuit?

Keep if not dented.

Unprotected.
They were both light blue Samsung ICR18650-20 laptop pulls.

+1 to that

How many feet can you get an 18650?

hahahaha I actually had one jumping out of the charger the other day. but i aught it with y left hand while it already had passed me on the way down (neven know I could be this fast :wink:

Hmm, interesting to mark cell pairs with a wrapper, might just order a few of those, thanks for the link

Ha Ha Ha. I just spit my mouth full of water out laughing at that one. I’m NOT the only one. Good one my friend :smiley:

Wisest thing my daddy ever taught me who was the best engineer I've ever known.

"Son if it ain't broke don't fix it"

My dad 1986

The battery looks perfectly fine to me, I don’t see anything wrong.

Woah … feet? Are you replacing the springs in your charger with extra-strong springs for more distance? :sunglasses:

Does having a 10180 stovepipe in my charger count? That’s happened a few times here :blush: Wee little beasties those are in a big charger bay.

I must sadly report the loss of another of my LiIon cells, a 14500 this time. It was in my SK68 clone and dim, when the light shut down I thought I’d clicked it off but apparently I hadn’t. Later in my VC2 it read “0” volts and my DMM showed 0.007V. Shame on me- and it was an Efest too :cry:

Phil