What should I do to prevent this from happening again?
I am a little scared to try this again, I just bought two JR 4.8v 600 Mah batterys.
I want these to last a little longer.

Another question on batteries, I noticed that the Batteries that came with my flight JR packs are shrink wrapped in black.
The ones I just bought are red, does this mean they are old stock?
They are new in the package, but is there a shelf life on them?
Say they are new never used but have benn sitting on the shelf for a while.
Are they still OK?