Dodgy Bonka battery

One of my Bonka Batteries has started doing this after only a couple of charges
two questions… is it safe to fly with?
and is there any kind of warranty (Paul?)

Dave UK

Nasty. That looks like something hit it. I personally would not use it.

Not been near any impact just swelled up over a couple of days

A little melting on the outer layer plastic?
Need a better resolution pic
What ever it is - I would not use it.

Definitely not safe to fly with.

Yeah, you are right, don’t use it again, broken battery is dangerous.

You might have hit something without noticing. Ive never seen a cell swell like that. Shoot me a message, you can get single cells to replace if you want.