Puffed lipo.

[BeachBuggyPhil]

One cell of a two cell battery has puffed so much it's cracked open the hardcase and got worse and worse.
I've just cut the wires and balance lead off but how can I make it safe?
I've heard a bucket of salt water works. How long do I leave it?
Any other options?
I'd leant it to someone who I think discharged it in their car, left it a couple of days and didn't balance charge it when charging it back up from empty!
Lucky it wasn't expensive but worked well and will be missed.