Even more help Anyway, I ran into a problem. AJ mentions how a lipo can puff up and I am experiencing this. The very battery that came with my F-18 is doing this same thing. It is puffing up and does so more and more after each flight and charge and I am afraid this thing is about to blow up. I am not sure why it is doing this, I never modified anything in this plane and its all original. I notice the battery is listed as 18C but on the site it says the F-18 has an esc that is a 20amp which makes me wonder if this is the problem? If so I need to contact hobby lobby and see if they can send out another battery. I will not dare attempt to use this battery I got again.