It has been cold and windy the last couple of weeks in Colorado so it has been about 10 days since I flew my spark. I charged my batteries before I put them in my backpack and they have been in a nice warm bedroom since then. It got up to 47 F today so I went to fly again. I was surprised all 3 batteries had discharged considerably the one that was in the drone was at 1/2 and the other 2 were at 3/4 charge, I got a total of 17 minutes out of all 3 batteries according to my flight data. I guess you have to charge them just before you go fly. I am wondering if this is normal & what others are experiencing? What kind of flight time are you guys getting out of a fully charged battery? Thanks Ron