Another one...... 6 month warranty for batteries......Step up DJI! I have Li-Po battery's that are 15 years old that still work perfectly with Zero swelling.

You gotta land when you are at 40% battery if possible.  Recharge to 100% before storage and do a 2 day discharge.

AntDX316 Posted at 7-23 17:05
You gotta land when you are at 40% battery if possible.  Recharge to 100% before storage and do a 2 day discharge.

That makes no sense. If the batteries require you to land at 40% then they shouldn't say 40% capacity remaining. So the 31 minute flight time is more like 20?

fans848f7190 Posted at 7-23 17:07
That makes no sense. If the batteries require you to land at 40% then they shouldn't say 40% capacity remaining. So the 31 minute flight time is more like 20?

Because it puts too much stress on the battery to run them all the way down and leave them discharged when not using.  It should always be at 60% when storing.  This is known in the DIY hobby but with consumer ready drones like DJI, the proper methods are neglected.  The only way to tell who doesn't know what to do is when people show videos like yours.

I've had my batteries since last year and none are swollen.  I even had flown them with +8 m/s ascend and +6 m/s for a while.

AntDX316 Posted at 7-23 17:23
Because it puts too much stress on the battery to run them all the way down and leave them discharged when not using.  It should always be at 60% when storing.  This is known in the DIY hobby but with consumer ready drones like DJI, the proper methods are neglected.  The only way to tell who doesn't know what to do is when people show videos like yours.

DIY Hobby? Check. I've been in the hobby since Ni-Cads. Then the new Ni-Mh's came out who...hoo. I have  Li-Po battery's that are 15 years old that have not swelled. The Issue here is DJI's battery is a smart battery and these should not be swelling. There are hundreds if not thousands of people with the same issue.

Li-Po No No's
Overcharge                                     DJI's system won't let this happen.
Over Discharge                                DJI's system won't let this happen.
Long Term Storage at full charge       DJI's system won't let this happen.
Hot charge                                      DJI's system won't let this happen.

Heat is one of the main reasons why Li-Po's puff up.  No off the shelf product should have a battery that get's hot enough to damage itself especially on a drone. If I build a quad / boat / car and take it out for a test drive and my battery is getting Hot I know I need a larger battery or a higher discharge rated battery.

fans848f7190 Posted at 7-23 17:43
DIY Hobby? Check. I've been in the hobby since Ni-Cads. Then the new Ni-Mh's came out who...hoo. I have  Li-Po battery's that are 15 years old that have not swelled. The Issue here is DJI's battery is a smart battery and these should not be swelling. There are hundreds if not thousands of people with the same issue.

Li-Po No No's

yeah, I have 4 batteries and none have any swell as I did the flat y-axis test like you did here.

tacking on everything irrelevant will not solve the problem

As I've said, 40% then land, store at 60% or 100% with 2 Day discharge.  If we add years of experience, comparing other things, saying it should never happen, etc. etc. it won't solve the problem.  Replace batts and do as I do.  We will get people who won't care about any of this.  I'm telling you a plausible solution.

AntDX316 Posted at 7-23 19:41
yeah, I have 4 batteries and none have any swell as I did the flat y-axis test like you did here.

tacking on everything irrelevant will not solve the problem

Irrelevant?  The point is I have 15 Li-Po battery's, some don't even have balance tabs that are 15 years old and none of them have swelled With all the DJI Smart features and automation going on this should not happen to their battery's let alone within a year. If these where $50 batteries it wouldn't be such a big deal but at $150 a pop it's crazy. If we should be landing at 40% DJI's battery capacity meter shouldn't be saying 40% battery remaining, I do understand what your saying but DJI needs to address this. Thanks

fans848f7190 Posted at 7-23 19:48
Irrelevant?  The point is I have 15 Li-Po battery's, some don't even have balance tabs that are 15 years old and none of them have swelled  With all the DJI Smart features and automation going on this should not happen to their battery's let alone within a year. If these where $50 batteries it wouldn't be such a big deal but at $150 a pop it's crazy. If we should be landing at 40% DJI's battery capacity meter shouldn't be saying 40% battery remaining, I do understand what your saying but DJI needs to address this. Thanks

DJI doesn't need to address it.  If they change something that works we will see new problems.  Just do as I've said and it would work.

I fly to 20-25% not 40% thats far too gentle.  Also DJI did address the issue,  the last update changed the discharge delay to 2 days,  which was 10 when they launched the product.

Dirty Bird Posted at 7-24 00:07
The fly only to 40% thing is complete bunk.

Exactly - I fly to 10-15% most of the time - never had a swollen battery

Dirty Bird Posted at 7-24 02:59
Same here.  Always 10-15% when I land.  My batteries are holding up fine.  No swelling.

.

Dear customer, we are so sorry for the troubles with these three batteries, it is recommended to contact our support team www.dji.com/support with the serial numbers and the video, our team will further help.

DAFlys Posted at 7-24 01:38
I fly to 20-25% not 40% thats far too gentle.  Also DJI did address the issue,  the last update changed the discharge delay to 2 days,  which was 10 when they launched the product.

Yes i fly to 25% but after 90 charges on 3 batteries which are used pretty much 1 a day i have noticed that they are swelling a bit on the bottom when hot but go flat after they cool down. Does this mean they are dying or about to?

RK7dronzy Posted at 7-24 04:43
Yes i fly to 25% but after 90 charges on 3 batteries which are used pretty much 1 a day i have noticed that they are swelling a bit on the bottom when hot but go flat after they cool down. Does this mean they are dying or about to?

I have never noticed temporary swelling; two of my three batteries suddenly swelled dramatically after 3.5 years. I noticed after a flight while replacing the first battery and finding it almost jumped off the AC after the latches were depressed. I then checked my remaining batteries and found one more was swollen. As I fly every week this must have happened with the most recent charge cycle.

If your batteries are swelling while in use, they could swell so much during flight that the battery or battery contacts could disconnect, or even catch on fire, causing the drone to fall out of the sky. I'd recommend replacing them.

Dirty Bird Posted at 7-24 00:07
The fly only to 40% thing is complete bunk.

If you are flying for fun do 40%.  I have 4 batteries so it's fine but if I'm on a job and low on batts I may run them down to 20% or less but don't this all the time.  Just buy more batteries if you want to fly so much.  To me it gets boring.

Also make sure to use DJI-made chargers.  This is why I only use DJI parts straight off DJIs website.

Ex Machina Posted at 7-24 05:14
I have never noticed temporary swelling; two of my three batteries suddenly swelled dramatically after 3.5 years. I noticed after a flight while replacing the first battery and finding it almost jumped off the AC after the latches were depressed. I then checked my remaining batteries and found one more was swollen. As I fly every week this must have happened with the most recent charge cycle.

If your batteries are swelling while in use, they could swell so much during flight that the battery or battery contacts could disconnect, or even catch on fire, causing the drone to fall out of the sky. I'd recommend replacing them.

Oh great, so my bird could fall out the sky at any moment if these batts are failing. So a year into a four year project (unpaid) i am going to have to replace the batteries another 3 times at a cost of £1300. Dji quarentee is six months or 200 charges. Is there a legal point here about false advertising regarding flight time without damaging batteries.

Dirty Bird Posted at 7-25 02:51
Everyone should keep a close eye on their Mavic 2 batteries.  How many packs are failing as a percentage of total packs in service is unknown.  Though the M2 battery issue is common, my suspicion is most packs are working properly.  Mine (3) are 22 months old & show no signs of failure.

Over recent years, there have been reports of swollen batteries to newer drones, none I remember with the Phantom 3 Pro that I still use and the 4 old batteries are still holding up well.
I was curious about how you use your batteries because this might well shed more light on the issue of swelling.
Do you fly hard and fast for extended periods of time?
Do you fly in a hot environment? A summer's day in UK would be a warm environment.

According to LiPo manufactures tech literature, the 2 things that individually greatly shorten the cell's life, is over-discharge, (but still within the cell protection circuitry limits) and high internal temperature.
I have always landed soon after the 30% warning and probably never gone lower than 15%. That is because of personal preference, not because I know more than anyone else.
DJI's % level is not an absolute measure like 35mm is. We cannot know what the designer decided was a safe trade-off between flight time and good battery life. Zero % might, for all I know, leave an actual 10% or more in the battery. They know that if the batteries fail before the waranty time, they are the ones that end up paying for a replacement battery and that isn't good business.
I seldom hammer the drone by flying flat out in sports mode or constant dodging and diving, because to me, it is just a camera. None-the-less, on a sunny summer day, the battery case is about 35 -40 dec C. The point about that is, the heat withinn the cell is still working its way out of the assembly of cells, so the case is no guide to cell temperature.
Your long battery life, DirtyBird, gives me hope that my batteries will last several more years yet.

I wonder how many owners of early laptops remember the short lives of their batteries. Always plugged in and charging, a hot computer. Then you needed to run it solely on the battery. I always found that after that, the battery wouldn't hold its charge, ever again. Same with old phones.
For me, this supports the manufacturers literature about poor charge/discharge control, over discharge being a battery killer and high temperature damage to the battery chemicals. Of course, swelling didn't happen because of the metal case and gas vent valve.

Dirty Bird Posted at 7-25 05:16
I fly in all weather, hot & cold.  I rarely fly in Sport mode, but I never land before they drop to 10-15%.  Sometimes I have gone to virtually zero, including once or twice with my Mavic 2 Pro.  When I return home & the batteries have cooled, I recharge them fully & return them to the case awaiting the next flight.   

If more than 3 days have passed, I recharge them again before flying.  All batteries & RCs are charged at least once monthly.  (I have 10 birds so some may go unused for a bit)  I would say my batteries get a good cycle whenever I fly.  I certainly do not baby them in any way.

Thanks, DirtyBird. I seem to have missed seeing your recent epic videos this year.  Most vids I see on here are unable to hold my interest (boring), but one of yours, in particular, kept me on the edge of my seat.
Keep up the good work.

Dirty Bird Posted at 7-25 02:46
Going to have to disagree with you on chargers as well.   Aside from my Phantom 2, I have always used aftermarket chargers capable of concurrent charging of batteries & RC.  I have experienced no problems.  In the DJI battery design, the charger is simply a power source.  Charge control is handled by the battery electronics.

These are smart batteries.  They might be using something that talks to the DJI chargers properly w/ feedback.  W/o the feedback it's working on assumptions and assumptions are dangerous.  The results are it inflates the batteries resulting in a pop-out mid flight.  If you get lucky using a non-DJI charger and non-DJI batteries and it works then great but there is a lot more that goes on with DJI products imo that makes it talk to each other (the drone) better that prevents such issues so you can fly over extremely expensive solar panels w/o worrying about taking out the grid and getting sued for millions.  It's like when I motorbike at well over triple digit speeds, I mean I assume everything would work and it has been working.  Along the way I've discovered and fixed certain things after knowing how they work but in the beginning, I had no idea (got lucky a few major times that people wouldn't believe but I do know what happened after).  The idea is to know why things work and how to maintain it but as we know how life is, we have to assume things will work or at least in the beginning just at least do it with reliable select components from reliable sources but even those can also fail but usually fail more when they are handled improperly over it's ownership.

Somethings we can do nothing about by the constraints we have available but at least put massive emphasis on doing it right with what you can do.

Dirty Bird Posted at 7-24 10:57
I assume you are talking about batteries for another model?  The Mavic 2 was released on August 23, 2018, so there are no 3.5 year old M2 batteries.

Yup, mine's an original Mavic Pro.

RK7dronzy Posted at 7-25 00:32
Oh great, so my bird could fall out the sky at any moment if these batts are failing. So a year into a four year project (unpaid) i am going to have to replace the batteries another 3 times at a cost of £1300. Dji quarentee is six months or 200 charges. Is there a legal point here about false advertising regarding flight time without damaging batteries.

So today after flying my one remaining battery I think I noticed some slight swelling of the bottom part of the battery. Maybe this is a common thing that escaped my notice till now, or maybe my last remaining battery is about to give up the ghost? ¯\_(ツ)_/¯

The swelling went away, and was nowhere near enough to risk pushing the battery away from the mount, but, yeah, there was some swelling. It was around 90 degrees Fahrenheit today, fwiw.

RK7dronzy Posted at 7-24 04:43
Yes i fly to 25% but after 90 charges on 3 batteries which are used pretty much 1 a day i have noticed that they are swelling a bit on the bottom when hot but go flat after they cool down. Does this mean they are dying or about to?

If they're not flat there not safe to fly,  they could very easily pop out during the flight.

DAFlys Posted at 7-27 00:12
If they're not flat there not safe to fly,  they could very easily pop out during the flight.

They are flat when they are cool but not when hot after flying. I have a elastic band in place just in case, but if dji are not going to replace them i can not afford to at the moment so will have to risk it until they get worse. I have done all to look after them so i think this is a possible manufacturing issue  . 90 charges does not seem very good at all.

RK7dronzy Posted at 7-27 01:57
They are flat when they are cool but not when hot after flying. I have a elastic band in place just in case, but if dji are not going to replace them i can not afford to at the moment so will have to risk it until they get worse. I have done all to look after them so i think this is a possible manufacturing issue  . 90 charges does not seem very good at all.

May be we can put a cable tie around battery and body to ensure that it will not fall apart.

RK7dronzy Posted at 7-27 01:57
They are flat when they are cool but not when hot after flying. I have a elastic band in place just in case, but if dji are not going to replace them i can not afford to at the moment so will have to risk it until they get worse. I have done all to look after them so i think this is a possible manufacturing issue  . 90 charges does not seem very good at all.

Probably is, when they swell they can loose contact and your drone will fall from the sky,   and that certainly costs a lot less than a battery.

kykmavic Posted at 7-27 02:07
May be we can put a cable tie around battery and body to ensure that it will not fall apart.

You may experience a slight bit of puffing out when fully charged to warm but thats fine as long as they don't swell up or split.

7/7 of my batteries are now swollen to the extent they easily dislodge in flying.  All under 30 cycles.  Bought in 3 different batches with 18 months between the first and last.
Never flown below 30-40%.

The first 3 (my original fly more) went 7 months after purchase.  DJI didnt want to know.

My theory is these lipos REALLY hate operating in hot environments.
I've now had to spend half the cost of the drone again just on batteries to keep it flying.

gnirtS Posted at 7-27 07:46
7/7 of my batteries are now swollen to the extent they easily dislodge in flying.  All under 30 cycles.  Bought in 3 different batches with 18 months between the first and last.
Never flown below 30-40%.

Yikes!

Please vote on my battery life poll if you feel so moved: https://forum.dji.com/forum.php?mod=viewthread&tid=219268

I don't know what to think anynore with these M2P batteries. I own 4 of them, manufactured between August and September of 2018. 3 of them started swelling within the first year of use and with less than 30 cycles on them. Then during the lockdown, they went back to normal while stored. One of them got swollen again after a couple of charges and uses and the other 2 are flat again. Go figure!

I'm thinking that because of the hotter climate we have here (Greece), might be a factor to consider. Even when storeed in the  case, on a hot summer day they can get up to 35-40 degrees. I assume that when flying, they can get a lot hotter in this enviroment. Although I always keep my eyes on the voltage during flying, I can't help but thinking that a failure mid-flight is possible because of the high temperatures.

xagoras Posted at 7-28 01:19
I don't know what to think anynore with these M2P batteries. I own 4 of them, manufactured between August and September of 2018. 3 of them started swelling within the first year of use and with less than 30 cycles on them. Then during the lockdown, they went back to normal while stored. One of them got swollen again after a couple of charges and uses and the other 2 are flat again. Go figure!

I'm thinking that because of the hotter climate we have here (Greece), might be a factor to consider. Even when storeed in the  case, on a hot summer day they can get up to 35-40 degrees. I assume that when flying, they can get a lot hotter in this enviroment. Although I always keep my eyes on the voltage during flying, I can't help but thinking that a failure mid-flight is possible because of the high temperatures.

I live in the tropics where ambient temp is 30-35c all year round.

The Mavic 1 batteries a few started to swell but that was after 2 years of heavy use so completely acceptable.

The M2s as i said all 7 i have, from different months and years of manufacture ALL did with under 30 cycles.

Interestingly, electrically they seem fine, cells remain balanced throughout even with deliberate heavy use and so on.  The swelling is a physical threat.

2 of mine are so swollen the power on/off button is stuck and wont depress after a flight.  I have to remove the battery (easy as its always popped out one side), wait for it to cool THEN battery can be powered off.

Reading all the different post and threads and youtube vids it definetly seems that there are batches of batteries that are not up to the job and dji know all about it. Giving a six month warranty and the updates confirms that. Why is it you can get a 5 year warranty on li-ions  but not on li ion polys which is what these are. Any other manufacture would be doing a recall and dji will not. 2018 seems to be the worst year. Suggesting we contact customer support which i will do seems like a cop out if they are not going to replace all affected batts free of charge. Or being synical is a way of getting these post of the forum, as it is starting to affect sales. Why buy a dji drone if it is going to cost more in batteries.

AntDX316 Posted at 7-23 17:23
Because it puts too much stress on the battery to run them all the way down and leave them discharged when not using.  It should always be at 60% when storing.  This is known in the DIY hobby but with consumer ready drones like DJI, the proper methods are neglected.  The only way to tell who doesn't know what to do is when people show videos like yours.

I've had my batteries since last year and none are swollen.  I even had flown them with +8 m/s ascend and +6 m/s for a while.

What is the room tempereture where you store the batteries?

An expert said that when the storage temperature is relatively high (more than 25C) then the internal resistance of the battery increases gradually. The result of the increase internal resistance is the swelling of the battery, something which is irreversible.

kykmavic Posted at 7-29 13:06
What is the room tempereture where you store the batteries?

An expert said that when the storage temperature is relatively high (more than 25C) then the internal resistance of the battery increases gradually. The result of the increase internal resistance is the swelling of the battery, something which is irreversible.

regular room temp but throughout the year, they are in their own backpacks so when I have a need for each of them I just pull that one out

Only the inspection work is where I use the P4Pv2.0 otherwise it's always M2P.  Never used the M2Z in a long time.

Hi all, I'm new here with a Mavic 2 pro,  I have 3 batteries and want to do all I can to keep them healthy.  I have read this thread, the "Battery care is more important than you think" and the "Intelligent flight battery safety guidelines" pdf, and chatted with tech support but still not 100% sure.  
Lets outline several scenarios,
1- I fly and the battery is between 40 and 60% after flight, then I would just store it right?  I mean, why bother charging it to 100% if it's just going to discharge to a 40-60% storage level if I don't fly within 10 days?  
2-I fly and the battery is at 30% after flight, then I would charge it to between 40 and 60% and store them if I'm not planning on flying within 10 days.  
3-If after flying, I want to use the same battery to fly again that day or the next day, I would wait until it cools, then charge it to 100% in anticipation/preparation of the next flight.
4-Generally speaking, before flying, fully charge the flight battery.  
Does this cover it in a nutshell?
Thanks!

Also just watched, Mavic 2 Battery - Best Practices & Proper Care from Quadcopter Guide, very good.

No number of guides can change the fact that batteries, looked after and used properly, are swelling after very few cycles as seen by many many people.

Especially those in hot climates.

gnirtS Posted at 8-4 06:32
No number of guides can change the fact that batteries, looked after and used properly, are swelling after very few cycles as seen by many many people.

Especially those in hot climates.

Correct! This is a fact and there is no more evidence for it!
Batteries, at least those manufactured last year and before, have a serious issue, no matter how they are treated!
Every one has a mobile phone, in cold and warm climates, but these batteries do not change their volume whatsoever.
Certainly, the current drawn on Mavic is much higher and temperature of these batteries is quite high, but the design must be such that they “respect” the money all those customers pay to a manufacturer, trusting to their products. And, as the least respect to their customers, even if they are not responsible for it, the manufacturer must replace those swollen batteries for their precious customers.

Its M2 specific.  Although they did swell, my M1 batteries did it in about 2 years and 100s of cycles which is completely expected for routine use.
Thats a lot different to 7 batteries, from different months and years all doing it within 20-30 cycles in my case in identical climate.