jmir

My Feedback: (1)

I had an unplanned landing. A bad one.
My 3S2P 11.1v 4300 mah li-po got smashed in the process.
It recharged without any problems, but I'm hesitant to fly with it.
Would you risk it? Any comments?

Attached is photo.

Matt Kirsch

My Feedback: (21)

Attempting to charge a damaged pack is way riskier than attempting to fly with one. All of the LiPoly incidents that have happened to people I personally know occurred during the charging process. Packs do occasionally go up in the plane, but generally only immediately after a crash or if the pack is being used way too hard.

Let the pack sit a few days, and measure the individual voltages on each cell. They should be within .01V of each other. If not, and/or the voltage has dropped signifigantly from 4.2/cell, I would dispose of the pack by discharging to 0V, then soaking in salt water.

jmir

My Feedback: (1)

Matt,

Thanks for your comments.
I think I will try and fly with it. Take it up for a couple of minutes and see if it overheats.
Then, keep on pushing it at higher throttle settings, bringing it down every minute or so, to see how it behaves.
Again, thanks for advice.

Jmir

jmir

My Feedback: (1)

Well, I fully charged the pack without any problems and I took it to the field today.
I flew my E-flite Ultra Stick 25e for a couple of minutes just slow circles. Brought it down and the battery was cool to the touch.
Took it back up and flew it a little faster the next time. Brought it down and the battery was just luke warm.
Flew it for about 5 minutes, mostly at full throttle with a few seconds off every now and then. The battery was a little warmer, but not warmer than my other good batteries.

So, I think I'll just keep my eyes on it while charging but use it like any other battery.

Teenage Pilot 14

You really can't be too careful with lipos anyway.... I suggest putting it in a big soup pot with a lid while charging. That's what I do to make sure I don't burn anything down (like the house...). At the first sign of questionable behavior, though, get rid of it with the method stated above, or you could always take it to a big field and shoot it with a rifle from a few hundred feet away to make sure it's really destroyed

jmir

My Feedback: (1)

That's exactly what I've done with this battery. I put it in a large metal pot while charging just to make sure.
As to bad/worn out li-po's, I take them to the local Radio Shack store where they have a free disposal program for used batteries.