I've bought 2 year ago 2 power pak 5.0x2 pro (s/n 273522 and 273525), plugged them on a PB competition and installed the whole in my new Carf Su31 last year and made few flights before the lock down, the aircraft was stored till then.
Last week-end, I tried to charge the batteries but that was impossible to have the green light.
As I could not have a view on the screen of the PB competition and wanted to be sure of the voltage, I've decided to remove the Pak ... The voltage of both of the bat was under 6V
Since I had 2 new power pak 5.0x2 pro in box (bought one year ago, s/n 291414 and 291404) and I decided to change the 2 "old" pack by the 2 new ones (the voltage of the new ones out of the box was 7.4V).
After one day charging the green light appeared on the "old" ones (s/n 273522 and 273525), but what about the realibility now after that deep discharge?
I've read there is an issue with the electronic internal controleur, that means I will have the same problem each time I store the aircraft for some times.
What should I do with these batt?
Talking about the new one (s/n 291414 and 291404), a battlife guard was plugged on the batt, but on the back the dot is silver grey (not yellow), what about this version?
Thank you for your help