A Wounded 18650:

[DigitalGreaseMonkey]

About a week ago I was loading 18650s into the chargers when I fumbled one. It dropped about six inches, the protection circuit landed on a hard plastic corner of one of the chargers. Sure enough, that was all it took. We all know how forces get magnified when concentrated in a small spot, so I was not surprised.

These were new Trustfire gray cells, 2400 mah. I am liking these cells very much, so am reluctant to send this off to recycling heaven. I got curious and removed the plastic wrap. I carefully lifted up the protection circuit to get some slack and cut the connection to the positive end. I was able to fully remove those ribbon connections and now I have an un-protected cell.

The white plastic ring that fits around the button top is adhesive and went back on. There is still a thin layer of plastic around the case, except for the end.

The volt meter shows 4.20 volts, and the ZTS pulse load tester shows 100% capacity.

For the more experienced folks out there: Are there any concerns or surprise issues I should worry about if I use this cell with my other un-protected cells?

The other un-protected cells, which came "free" with one of my Solarforce lights, are also 2400 mah rated and I suspect they came from the same factory. They just happen to be Solarforce branded. The reason I suspect a common heritage is because of the shape and tooling marks on the button top. (I understand that it is possible that the case components may be sourced to many different companies.)

Any thoughts?

Best regards,
DGM

 

[Fallingwater]

Once the protection is removed the cell is just a simple unprotected 18650, and treatable as such in all aspects.

 

[DigitalGreaseMonkey]

Once the protection is removed the cell is just a simple unprotected 18650, and treatable as such in all aspects.

Thanks Fallingwater, I had to ask even though logic suggested this was the case. Logic has failed spectacularly from time to time.

Best regards,
DGM

 

[greenLED]

If you can't determine further physical damage, it's probably OK to use. Do keep an eye on it for a few cycles, just to be 100% sure that the cell's structure and performance hasn't been compromised.

 

[DigitalGreaseMonkey]

If you can't determine further physical damage, it's probably OK to use. Do keep an eye on it for a few cycles, just to be 100% sure that the cell's structure and performance hasn't been compromised.

Thanks for the thought!

My personal view is that when playing with concentrated energy sources, whether it is gasoline or rechargeable batteries, eternal vigilance is the only sane way to travel.

The problem, of course, is that we really have no direct way of seeing what is going on inside these things. We are left with the old physician's conundrum, "Does it hurt when I do THIS???"

Best regards,
DGM