Wow, awesome reply, thank you. This new, to me, procedure will be challenging. I have never charged a battery to a "storage" voltage but will try in the future, especially with the more expensive 5 &6 S batteries. Upon viewing my charger, it does have a discharge feature. I don't know if it has a feature to set the discharge to a particular voltage and then cutoff automatically. SO, I will have to monitor the discharge if I use the charger.
With my calculations it appears that a "storage" voltage for 5 S batts is 19.0 volts and for a 6 S batt, 22.8 volts. Again, don't know how to set these voltages to auto shut off. The charger does shut off when 100% is reached. My charger is a Thunder AC 6 Dual Power. I now will not buy a dedicated discharger, but will use your methods to achieve this.
The other challenge is trying to decide when I should charge the batteries to 100% for flying since I usually make up my mind to fly in the morning depending on weather and projects.
Things can be complicated, sigh.