What I mean is if I have a lipo battery that is rated for 500-800 charges and I only want it as a backup battery how long will this battery last? That is to say is it 500 charges forever? Like if I take an unused lithium ion battery is 5 years old and start using it will the charge be just as good as if I used it brand new? And will I still get that 500-800 cycles?
Lipo battery last
The battery is rated to support 500-800 charging cycles before you will likely need to replace it. A 5 year-old battery may show some degradation, but you should likely still get somewhere between 500-800 charges although likely towards the lower end of the number.