Flight pack Nicads- 2 years or 90% whichever comes first.

Flight pack Li Ions/Lipos - 2 years

Transmitter Nicads - 3 to 5 yrs or 85% whichever comes first.


I then keep the Nicad packs for shop use (plane setup etc) for a couple more years and maybe for sport plane use until they reach 85%. Li Ions I keep around for shop use only.

Then again, I usually don't keep a competition plane more than two years<g>
I have always used new batteries in a new competition plane.


And then again, I was told many, many years ago 80% for Nicads.

It all adds up to what risk you are willing to take. I think the biggest thing to worry about, is damaged wires. I caught one just in time last season that had been chaffed through to the wire in one place. Inspecting your plane on a regular basis is a must.