Warm Batteries???

[Bikerbill]

My Mavic2 Pro currently has 3 batteries. It about 1 month since I got it. Everything is in a GO-PROFESSIONAL hard case with foam cutouts. It was sitting in my office today and I opened the case and as I removed the 3 batteries, I noticed 2 seemed warm. 2 batteries are 8-9 deg warmer than the case and 1 battery is about 4 degrees warmer. They were all charged about a week ago. The 2 that are warmer are showing 3 green while the coolest one is showing 4 green. What's going on????

 

[Mossiback]

You might have lost track of the days and the two warm ones are auto-discharging to a storage level. Pressing the power button resets the auto-discharge timer.

 

[apandia]

Yeah, happens due to auto-discharging of batteries. This is currently set to 10 days. If you have not used the batteries for that long, it will start discharging it to make sure your batteries are not damaged due to retaining high level of charge without using it.

 

[Bikerbill]

Thanks for quick reply. Do I just press for about 2 seconds the indicator button each battery? Kinda scared me when I realized this. Never thought about automatic discharge.

 

[Paul2660]

I would not leave them in a foam case for storage. They do get warm during self discharge and odds are a foam case will not allow heat to dissipate as fast. Just a thought.

Paul C

 

[Mossiback]

...Do I just press for about 2 seconds the indicator button each battery? Kinda scared me when I realized this. Never thought about automatic discharge.

Just a single quick press that shows the charge level will reset the discharge timer. The auto-discharge is there to protect the batteries so you should let them discharge when they need to. You just need to be aware to check the batteries before you fly if they have not been used for a while to insure they have a full charge.

 

[Mike4884]

Dude u definitely should not be leaving those dji batteries charged up sitting that long....dji's "10" day discharge cycle is wayyy to long for lipos.....anyway your 2 batteries were probably discharging. I suggest for way better lipo performance , no swelling and alot more cycles then u will get at your current rate that you do not leave them charged. Just charge when u go out to fly or for next day. Then when done and u are going to leave them sit for a while leave them around 40% thats a nice storage charge should put u around 3.85 v per cell maybe 3.87v....good luck and u will save money if u take care of them. Remember lipos are fussy like to be treated like the misses gotta show a little tlc??? ? true story. Seriously though u will thank me later.... I have to many lipos to count....ranging from 14s stick packs for my heli's to little 1s packs been through the motions

 

[MAvic_South_Oz]

When a battery is in the drone and that and the app are on etc, you can click on the battery icon in settings and change the default to X days, as preferred.
I think it can be anywhere from 2 - 10 days . . . I set mine at 5 days, but think it is reset if there is a firmware update too, so pays to check now and then.

This place in the app is a good one to visit now and then as you get all sorts or battery data, and it helps keep an eye on flight time per battery and rotating batteries if you have several.

It's recommended to keep discharging batteries in a safe discharge location, but then DJI instructions themselves don't mention this, and say things like to fully discharge batteries before airline flight, so who knows how correct their own info is.
https://dl.djicdn.com/downloads/mavic/Mavic+Pro+Intelligent+Flight+Battery+Safety+Guidelines-EN.pdf

Some other interesting things listed in the DJI battery link pdf . . .
Batteries should be removed from the drone when stored for longer periods (what, 1 week / 1 month / more ?).
You should always monitor batteries when charging (they have been known to catch fire / explode during the process).

(Edit - I think the Air doesn't have the choice of discharge days either, think it's just set for 10 days.
You have the M2 anyway, so should find that ok.)

 

[Mike4884]

Nope as far as i know and experienced u cannot change rhe default 10 day on the mavic 2's i know i do not have the setring on ios or android.....and i have no clue why dji thinks 10 days was just a good # .....so u have to pay a little more attn with the mavic2 batts.... And yes i dont recall having ot on my air ...i know my p4p's had it. I would keep it at 2 days, oh my old p4 had it too....cant remember if my original mav pro had it but 90% sure it did....and 5 days is to long imo still? but hey just my opinion. Also i would check on batteries while in storage for a month or more. lipos tend to lose charge weekly so some people come back to totally flat lipos. Also really good piece of advice just plz dont ever follow dji's guidelines on lipo's ever! If u guys want real legit lipo tips there is a couple great links i can grab. Used them for years. ......haha reminds me dji's instructions on trouble shooting my friends lipo ....my buddy calls me and tells me he says they told me to take the lipo and run it flat let the drone land and let it go to 0 % ....seriously dji? Yea u might have smart boards in there but its still a lipo and even if there is reserve it brought his lipo to 3.45 v a cell ....yea hardly healthy for lipos and what happened to the 80/20 rule? 80 out / in 20 on reserve healthy nominal voltage ....3.70 per volt ....maybe figure out some better way to calibrate the smart board in the lipo? Lol good times good times....im just ranting....good night?

P.s his lipo never "calibrated" it was shot....

 

[MAvic_South_Oz]

and 5 days is to long imo still? but hey just my opinion.

I've read similar opinions, and why . . . think I might change mine to 2 days, usually try and fly em down on the day, but sometimes I have a couple down to say 30% (which I'm happy with as a mark to aim for) the other 2 fully charged taken home and often I don't fly for a week or maybe 2 weeks.

So 2 days might be a better target.
I'll have to remember to leave them out of my backpack battery compartments, while not tight foam, they may still not be good on dissipating heat while discharging.

Weird the M2 not having this option in their menu (or the Air for that matter), I hope the MP/ MPP option still there, haven't checked battery info for a while and possible I did a firmware upgrade since, so I'll have to check that out again, change to 2 days if so.

 

[Mike4884]

I've read similar opinions, and why . . . think I might change mine to 2 days, usually try and fly em down on the day, but sometimes I have a couple down to say 30% (which I'm happy with as a mark to aim for) the other 2 fully charged taken home and often I don't fly for a week or maybe 2 weeks.

So 2 days might be a better target.
I'll have to remember to leave them out of my backpack battery compartments, while not tight foam, they may still not be good on dissipating heat while discharging.

Weird the M2 not having this option in their menu (or the Air for that matter), I hope the MP/ MPP option still there, haven't checked battery info for a while and possible I did a firmware upgrade since, so I'll have to check that out again, change to 2 days if so.

30% is perfect especially for a storage charge or just sitting around till u charge again this is exactly what i do puts us around 3.78v per cell which is a good storage voltage, till the next time u fly. If im flying consecutive batteries before my day of flying is over i do take batteries down to 20% but its your last batteries of the flights for day that make it easy just to stop at 30%....only time u will want to maybe increase this "storage charge" to 45% or 50% is if u are going on vaca or will not fly for a few weeks to a month....because remember lipos always lose some charge when sitting around for a few weeks....so u would come back to a lipo lets say 3 weeks from now maybe at 30% vs 10% or worse 0% and sometimes irrecoverable.....and i know i dont know why dji left that very important feature out....or just didnt care enough ?‍ sorry for the wall of words.

P.s 2 days is perfect this is what ive always used. When i had the option lol

 

[Bill combs]

You might have lost track of the days and the two warm ones are auto-discharging to a storage level. Pressing the power button resets the auto-discharge timer.

i wish i could change my discharge cycle from 10 to 7 days i don’t know why dji changed that from the other drones i have?

 

[ScheisseKopf]

 

[Kilrah]

Just a single quick press that shows the charge level will reset the discharge timer.

Not with the Mavic 2, you need to actually turn them on.

 

[Bikerbill]

Thanks for the video clip above. Sure it was a long video but I learned much. And thanks for all the other comments and thoughts and opinions.

 

[GGehret]

Dude u definitely should not be leaving those dji batteries charged up sitting that long....dji's "10" day discharge cycle is wayyy to long for lipos.....anyway your 2 batteries were probably discharging. I suggest for way better lipo performance , no swelling and alot more cycles then u will get at your current rate that you do not leave them charged. Just charge when u go out to fly or for next day. Then when done and u are going to leave them sit for a while leave them around 40% thats a nice storage charge should put u around 3.85 v per cell maybe 3.87v....good luck and u will save money if u take care of them. Remember lipos are fussy like to be treated like the misses gotta show a little tlc??? ? true story. Seriously though u will thank me later.... I have to many lipos to count....ranging from 14s stick packs for my heli's to little 1s packs been through the motions

I know I won't be able to fly as often this winter once it gets SUPER cold where I live, and plus the fact, that since I"m back to work--a teacher--my time will be limited. You say in the above post not to recharge them after a flight and then storing them around 40 percent? How many lights is that? I'm assuming two green lights represents 50 percent? I usually fly and bring my drone home after the first low battery warning and that's about 1 green light left--which, I am assuming, is too low for storage. So, what would you suggest...flying my usual, and then watching the recharge until only 2 lights show, or just make shorter flights? I guess I"m just wondering how I can tell they are at 40 percent before I let them rest for the winter? Thanks.

 

[paulatkin73]

So, old lipo chemistry was set to have optimal storage voltage at 30%. For new lipos, pretty much all current ones, including dji mavics - proper storage voltage is 3.8v per cell. You should not keep lipos long with more than 4v per cell, ever. So, if you know that you will not use drone in several days - just hover until battery goes to 3.8v per cell on the screen. It is a 60% charge level and it is ok.

 

[DGNOO]

Dude u definitely should not be leaving those dji batteries charged up sitting that long....dji's "10" day discharge cycle is wayyy to long for lipos.....anyway your 2 batteries were probably discharging. I suggest for way better lipo performance , no swelling and alot more cycles then u will get at your current rate that you do not leave them charged. Just charge when u go out to fly or for next day. Then when done and u are going to leave them sit for a while leave them around 40% thats a nice storage charge should put u around 3.85 v per cell maybe 3.87v....good luck and u will save money if u take care of them. Remember lipos are fussy like to be treated like the misses gotta show a little tlc[emoji8][emoji8][emoji8] [emoji23] true story. Seriously though u will thank me later.... I have to many lipos to count....ranging from 14s stick packs for my heli's to little 1s packs been through the motions

Hi
Please recommend best way to discharge batteries and to what level.
Mavic 2 pro.
Thanks

 

[JAW]

What about the batteries for the controller or, in my case, a CrystalSky monitor? Do they require special shortage if stored for longer than, for example, 7days?

 

[GGehret]

So, old lipo chemistry was set to have optimal storage voltage at 30%. For new lipos, pretty much all current ones, including dji mavics - proper storage voltage is 3.8v per cell. You should not keep lipos long with more than 4v per cell, ever. So, if you know that you will not use drone in several days - just hover until battery goes to 3.8v per cell on the screen. It is a 60% charge level and it is ok.

Thanks for the info. Now, please forgive my next question. I'm still a newby at this. When you say "on the screen", are you referring to my smart controller screen or DJI assistant? Also, how many cells are in each battery..just curious. Thanks.