The
batteries are intelligent and are self managed. I usually set mine to self discharge after 3 days of non-use.
With lipos, never store them fully charged or fully drained. It should be kept under 50% charge.
As per riseaboveaerials FAQ page:
Buy DJI Spark Fly More Combo - Rise Above Australia
Maintenance
How often should I fully charge my Spark batteries?
It is recommended to fully charge Spark batteries at least once every three months.
There is mention of "Hibernation mode".
My newly purchased battery is not responding when I press the power button. What should I do?
New batteries are shipped in Hibernation Mode. In order to activate your newly purchased battery, charge it fully.
And charging via USB
How long does it take to fully charge a battery?
When using a standard USB charger, it takes 80 minutes to fully charge a battery.
When using a Charging Hub, it takes 52 minutes to fully charge one battery, 55 minutes when charging two batteries and 85.2 minutes when charging three batteries at the same time.