You say stored on discharge, I hope you mean 30 to 50% charge which is what the hub will charge them to if set for storage. They shouldn't be left fully charged or fully discharged any longer than absolutely necessary. Cool and dry is the best storage environment so you did well there.I got them the beginning of January. Have been charged about 8 times. I store them in the hub on discharge and then charge them a day before I plan to fly. They are in my basement which is cool and dry.