Discharging Advice

[Rchawks]

Should MA2 batteries get warm while sitting idle in a hard case (fully charged) Is this simply heat generated during self discharge?

 

[z28lt1]

Yes, they may be warm during self discharge. The question is, now that they have self-discharged to an appropriate level, why do you want to run them down? They've done their thing, just charge before next flight.

That said, yes you can always run them down by charging something else or in the drone.

 

[Rchawks]

The batteries in question have 3 to 4 lights on, I think letting them sit idle for 1 or two weeks with full charge is what worries me, and I'm storing them in a GPC case with the foam which I would think hold the heat in a bit more than sitting on say a table in the open. Are you saying that a fully charged battery will discharge itself to a point of hibernation without outside input? It seems like that would take a very long time and I worry about case fatigue.

 

[InvisibleName]

The batteries in question have 3 to 4 lights on, I think letting them sit idle for 1 or two weeks with full charge is what worries me, and I'm storing them in a GPC case with the foam which I would think hold the heat in a bit more than sitting on say a table in the open. Are you saying that a fully charged battery will discharge itself to a point of hibernation without outside input? It seems like that would take a very long time and I worry about case fatigue.

Its all in the user manual & discussed in several threads on here.

Auto-Discharging Function: To prevent swelling, the battery automatically discharges to 96% of the battery level when it is idle for one day, and automatically discharges to 60% of the battery level when it is idle for
five days. It is normal to feel moderate heat being emitted from the battery during the discharging process.

 

[Rchawks]

I've seen opinions that the 60% discharge is still to high and that 30% is closer the the ideal point of storage. But as you say the manual states 60%. What do you think about the numbers? (thank you for the reply)

 

[z28lt1]

I'm not a LIPO expert, but 30% seems low from what I've ready. Commonly seen 40-60%. While for the Air 2, DJI only states it runs down below 60% for storage, for most of the other drones, they state storage should be at 40-60% to increase battery life. I don't think I'd try to out-think them here, and I know my DJI batteries have generally held up well over time

 

[Rchawks]

Thank you z28it1.

 

[old man mavic]

the storage level that DJI bring them down to is perfectly fine for long term storage ,its more to do with individual cell voltage ,and making sure you check them monthly and top them up to around 60- 75% if they need it

 

[Rchawks]

the storage level that DJI bring them down to is perfectly fine for long term storage ,its more to do with individual cell voltage ,and making sure you check them monthly and top them up to around 60- 75% if they need it

Thank you very much OMM.

 

[WithTheBirds]

I've seen opinions that the 60% discharge is still to high and that 30% is closer the the ideal point of storage. But as you say the manual states 60%. What do you think about the numbers? (thank you for the reply)

60% is marginally less optimal than 40% but a lot better than close to, or at 100%...... Probably not enough to worry about.

The advantage with 60% is it allows a buffer for the combined contribution of the battery SOC and cell self discharge (the SOC continues to perform cell measurements with the battery switched off).