What do you guys do with your Phantom 3 Std batteries if your not flying for 3 months or more (I know , I know .... go fly it , right ! can't )

Charge up fully and leave in cool safe area. Let the auto discharge system do its job.

If possible check every month or so to make sure pack is not too deep discharged. As long as one LED is solid you are ok ... preferably one solid and second at least blinking - is better ...

But we are supposed to be able to leave them for months - imagine how long they sit with sellers ... you think they are only days ??

Nigel

I need to check my flight packs, and recharge them.

I think I will go just that,  today. ;-)

You know, if flying is not possible, the onboard flight SIM can be used to deplete flight packs.
I place my running drone on an upturned fan, while playing around indoors...

RedHotPoker