Evening ALL
I’m off out tomorrow to a private estate for a spot of flying and just wanted to check the firmware etc is all up to date and as I was getting the gear out I noticed all 3 of my batteries for my MA2 are actually quite hot.
I keep them in Lipo bags and the room they’ve been in isn’t that hot just wondered if this is normal and has anyone else noticed this?
Thanks
Lee
When did you last charge them, and how many days is the auto-discharge set to?
They do get warm during auto-discharge.
Do they have the auto discharge, where the battery slowly discharges over a set period. I know that will generate some heat.
Edit:
Beat to it by Dave, must have been typing at same time
Last charged about a week ago. Auto-discharge?
For storage, it’s best that LiPo batteries are not stored for long periods fully charged … so DJI have firmware in their batteries that takes them down to an 80% (I think it is).
More about it in Mavic Battery Auto-Discharge - Why? How? Which models?
Hi Lee
Define quite hot 
Warm as a result of auto discharge is normal
Hot to the touch is not normal but if all three are the same and leaning to warm not hot than I suspect you have nothing to worry about
Cheers
Steve 
What @OzoneVibe and @Steviegeek said.
Most, well what few there are, drone manufacturers build in an auto-discharge feature to their smart batteries. At best smart batteries are over priced but suffer the same physical issues as regular hobby LiPo’s, left for long periods in a high charge state will irreversibly damage them. So manufacturers have built in a feature so that after a preset amount of time the cells in the smart battery will dis discharge at a slow rate. If you were to pick up one of the batteries during its slow discharge cycle it will feel warm to the touch compared to other items in the same area.
Interestingly not all manufacturers get this right the first time and it can prove costly. Powervision with the release of their PowerEgg X got the discharge algorithm very wrong and this resulted users, whom had left the battery in their drone, coming back a few days later to find the rear of the drone had malformed due to the excessive heat during the discharge cycle. Powervision had no choice but to replace everyone’s drone. It’s because of these random cockups, and DJI are not without some blame, that I never, EVER, leave a smart battery connected to a drone while it is in storage.
Nidge.
I do this all the time. On every drone I’ve ever owned (which granted, is no where near your crazy fleet 
)
Largely perhaps due to having no spare battery storage slot in the case for that last battery, so one always lives in the drone.
However, it’s usually the last battery I flew with anyway so it’s probably quite low in terms of charge state.
Interesting advice though.
Ditto everything you said, Rich.
Old habits die hard. I’ve always removed alkaline cells from my test equipment and other electrickery gadgets if I know I won’t be using it for some time. There’s nothing worse than opening a battery cover only to find the cells have leaked and all the electrolyte has corroded the battery terminals.
I’m especially cautious with the Anafi as it only needs one very momentary press of the power button to turn it on, so there’s a higher probability it could be turned on while in its storage case with other junk.
Nidge.
Just revisiting this thread.
I have to add my batteries for my FPV were warm today. I suspect self discharge causing this.
As @Nidge says, I also never leave a battery in any of my quads.
