Swelling batteries

[DanMan32]

That will be a challenge for those of us that have some swelling that would make it a concern, but currently not enough to cause it to unlatch.
Now I wish I didn't take apart my worst one.

 

[marcorasi1960]

I too have had problems with swelling Mavic2 batteries. Since I bought my drone a year ago I have used 8 batteries, an 4 of them are swollen and discontinued. There seems to be general consensus that batteries fully charged and subject to high heat is a major trigger for the swelling. So, I would like to describe my 'workflow' to you all and see if you have recommendations for me. I normally fly in the southern US, where it gets hot and humid in the summer. I usually fly for a couple of hours in the afternoon, starting with fully charged batteries and using them until they are about 5% charged. Then I go home and put my 4 batteries on a 4-slot recharger in a room where the temperature is constantly 82F or 28C. I then take them off the recharger when I get up in the morning, so they stay on the recharger about 12-13 hours. Then in the afternoon I go fly again and repeat the cycle. Is the temperature in my room too high? Is 12-13 hours too long? Could my half-hour drive to flight location be the issue? The car can get very hot here, but I turn on the AC full-volume, so the very hot period lasts only a few minutes. Any advice on what I should do differently would be appreciated!

 

[parkgt]

Keep your batteries in a cool cooler until flight time, return after.

Why not only charge to storage level in the evening and finish full charging the following morning before afternoon flights.

With these precautions my original four 20 month old batteries are still fine. May just be the luck of the draw

 

[thatswedishguy]

I too have had problems with swelling Mavic2 batteries. Since I bought my drone a year ago I have used 8 batteries, an 4 of them are swollen and discontinued. There seems to be general consensus that batteries fully charged and subject to high heat is a major trigger for the swelling. So, I would like to describe my 'workflow' to you all and see if you have recommendations for me. I normally fly in the southern US, where it gets hot and humid in the summer. I usually fly for a couple of hours in the afternoon, starting with fully charged batteries and using them until they are about 5% charged. Then I go home and put my 4 batteries on a 4-slot recharger in a room where the temperature is constantly 82F or 28C. I then take them off the recharger when I get up in the morning, so they stay on the recharger about 12-13 hours. Then in the afternoon I go fly again and repeat the cycle. Is the temperature in my room too high? Is 12-13 hours too long? Could my half-hour drive to flight location be the issue? The car can get very hot here, but I turn on the AC full-volume, so the very hot period lasts only a few minutes. Any advice on what I should do differently would be appreciated!

I would start by not flying them down so low. Lithium batteries do not really like to be below 20%. I never fly mine below 20% and I usually land at 25%. This also gives me a good margin in case the battery gauge is not reading the correct state of charge. This can especially be a factor in hot weather. Hard flying in sport mode especially in hot weather puts a lot of strain on the batteries. As much fun as it is, I only do it for short periods when it's hot outside.

Are you letting them cool properly before charging? Otherwise that could be your second issue.

The biggest issue is that you charge them full and then leave them on the charger. Big no no if you want them to last. They should stop charging at 100% but it could be that they discharge slightly and start charging again. Leaving them on the charger for so long also increases the risk of over charging if the charger is faulty. Not to mention it's a fire hazard to charge lithium batteries unattended. Especially high density ones like these. Also lithium batteries absolutely hate to be at 100% charge. They are comfortable between 20 and 80% and prefer being at 45%.

You should ideally store them at around 45% and charge as soon before use as possible. Unfortunately DJI doesn't have a storage mode on the Mavic charge hub like they do on the Phantom 4 hub.

A hot car can also be an issue. If you can, put them is something heat insulated before bringing them into the car. A cooler at room temperature for example. That should protect them for a few minutes. Never leave them in a hot car.

Are you using the official charger/hub? It's possible that some third party chargers aren't doing it right.

I have three batteries that I've had for a year now and with storage charge after letting them cool down I haven't had any issues. I have put 57 hours on my drone between the three batteries. I also store them in a cool place.

 

[marcorasi1960]

Thank you very much for your advice! I will try these things. It will be a bit cumbersome compared to what I am doing now. I have a 4-battery charger that charges them in sequence, so I can just hook them up and leave them there until they are all charged. To charge them only partially will require a lot of baby-sitting of the batteries one by one. But if that is what it takes not to have them swell.... Does anyone know if there exists a device that charges multiple batteries but stops when they are less than 100%?

 

[thatswedishguy]

Thank you very much for your advice! I will try these things. It will be a bit cumbersome compared to what I am doing now. I have a 4-battery charger that charges them in sequence, so I can just hook them up and leave them there until they are all charged. To charge them only partially will require a lot of baby-sitting of the batteries one by one. But if that is what it takes not to have them swell.... Does anyone know if there exists a device that charges multiple batteries but stops when they are less than 100%?

It is a lot more cumbersome, but it does make the batteries last much longer. The way you did it the batteries spent most of their time at 100%, which isn't ideal at all.

I can add that when I fly mine down to 25% it takes about 14 minutes to charge them back up to 45-50%. It's hard to know exactly what state of charge they end up at, but when I have put them in the drone and checked I'm usually just over 45%. The other thing I do is if I know I will only fly for 30 minutes for example, I charge two batteries and fly them down to 45% each (which takes about 15 minutes). Then they are ready to be stored without further care.

There are chargers that claim to support storage charge. I don't trust third party chargers, especially not from unfamiliar brands, so I won't link to any, but they do exist. Maybe someone else can recommend something.

 

[marcorasi1960]

Keep your batteries in a cool cooler until flight time, return after.

Why not only charge to storage level in the evening and finish full charging the following morning before afternoon flights.

With these precautions my original four 20 month old batteries are still fine. May just be the luck of the draw

Thanks for your advice. Unless there is a device that charges them only to storage level, that would require 'baby-sitting' each battery in turn... I guess it can be done, I just have spend much more time and effort doing that than I am right now. Thanks!

 

[marcorasi1960]

It is a lot more cumbersome, but it does make the batteries last much longer. The way you did it the batteries spent most of their time at 100%, which isn't ideal at all.

I can add that when I fly mine down to 25% it takes about 14 minutes to charge them back up to 45-50%. It's hard to know exactly what state of charge they end up at, but when I have put them in the drone and checked I'm usually just over 45%. The other thing I do is if I know I will only fly for 30 minutes for example, I charge two batteries and fly them down to 45% each (which takes about 15 minutes). Then they are ready to be stored without further care.

There are chargers that claim to support storage charge. I don't trust third party chargers, especially not from unfamiliar brands, so I won't link to any, but they do exist. Maybe someone else can recommend something.

Thanks again.

 

[Fleek]

I too have had problems with swelling Mavic2 batteries. Since I bought my drone a year ago I have used 8 batteries, an 4 of them are swollen and discontinued. There seems to be general consensus that batteries fully charged and subject to high heat is a major trigger for the swelling. So, I would like to describe my 'workflow' to you all and see if you have recommendations for me. I normally fly in the southern US, where it gets hot and humid in the summer. I usually fly for a couple of hours in the afternoon, starting with fully charged batteries and using them until they are about 5% charged. Then I go home and put my 4 batteries on a 4-slot recharger in a room where the temperature is constantly 82F or 28C. I then take them off the recharger when I get up in the morning, so they stay on the recharger about 12-13 hours. Then in the afternoon I go fly again and repeat the cycle. Is the temperature in my room too high? Is 12-13 hours too long? Could my half-hour drive to flight location be the issue? The car can get very hot here, but I turn on the AC full-volume, so the very hot period lasts only a few minutes. Any advice on what I should do differently would be appreciated!

Seems like a good and careful routine. I have had 4 batteries go bad with swelling. The fault is not with our care of them but with a flawed DJI product. Have you tried getting a refund on the bad batteries?

 

[marcorasi1960]

Seems like a good and careful routine. I have had 4 batteries go bad with swelling. The fault is not with our care of them but with a flawed DJI product. Have you tried getting a refund on the bad batteries?

Nope. Did you try? Any luck?

 

[Fleek]

Nope. Did you try? Any luck?

A lot of photos & back-and-forth queries on the first 2 swollen batteries. They were so swollen I didn't want them in the house as figured they might catch on fire or explode. Tossed them at a battery disposal place when I thought DJI had agreed on a refund. But Then DJI insisted I mail them the dangerous batteries! So all the effort for nothing.
Now I have 2 more bad ones & will try the process again for a refund. DJI needs to cover for this mistake. Wuhan all over again, ?

 

[Mike4884]

Thanks for your advice. Unless there is a device that charges them only to storage level, that would require 'baby-sitting' each battery in turn... I guess it can be done, I just have spend much more time and effort doing that than I am right now. Thanks!

U dont need a device to charge them at storage level. What i do is fly till 30% sometimes 25% i just stop flying by then in flight your voltage is 3.6 v across all 4 cells this is because u are in flight and using the lipo so why fly any lower? Not really good for the battery anyway. So i land at 25% (remember in flight voltage was like 3.6 to 3.5v per cell which is low) but when u land resting voltage is 3.75 to 3.80 per cell which is great and is whats called "storage voltage" ......so simply just flying to 25% and stopping u can put your battery away. It will be at storage charge. Now if you are not going to be flying for a couple of weeks you should check on the batteries because they slowly lose charge so if you're gone for a month you might come back to a 0% battery.... you do have to check them if you're not flying for a good while essentially you do have to babysit these things. But that is another thing people go wrong with they will just leave the battery sit forever for a month or two and then wonder why it won't charge again. Anyway so like I was saying your battery will be at storage at 25% even 30% is good just don't go lower than 25% and you can keep it sitting for a couple days/week.... I usually don't go more than a week without flying anyways.... and then when I'm ready I just charge the battery up that day that I go to fly. I have three batteries from 9/18 batt1 has 104 charges ....batt2 has 98..... batt 3 has 111 charges. They perform great show no voltage lag when I am in flight and have no swelling even after pushing sometimes in sport mode. Another tip I can give you is always keep an eye on battery voltage while in flight you can click on the battery icon up-top in app, and change the setting to show voltage (comes turned off and most people never notice this setting) and you can watch it as you're flying.... this setting is great because (example: say you are at 75% well now that you have voltage enabled to show next to the battery percent in app, if you start seeing 3.5 or 3.4 volts and you're at 75% battery something is very wrong and you should land.....this kind of gives you a little heads-up and gives you an idea of what's going on with your battery

 

[Mike4884]

It is a lot more cumbersome, but it does make the batteries last much longer. The way you did it the batteries spent most of their time at 100%, which isn't ideal at all.

I can add that when I fly mine down to 25% it takes about 14 minutes to charge them back up to 45-50%. It's hard to know exactly what state of charge they end up at, but when I have put them in the drone and checked I'm usually just over 45%. The other thing I do is if I know I will only fly for 30 minutes for example, I charge two batteries and fly them down to 45% each (which takes about 15 minutes). Then they are ready to be stored without further care.

There are chargers that claim to support storage charge. I don't trust third party chargers, especially not from unfamiliar brands, so I won't link to any, but they do exist. Maybe someone else can recommend something.

Turn on "show voltage" in battery setting in app this way u can see what voltage u have at that particular battery percent. Also 25% is fine that is about 3.75v per cell a little lower than I like to do it most of the time I try 30 so I will just land at 30 but 25% will suffice....so no need to charge back up to 40 -50% by the time u get to 50% u are probably at 3.9v per cell.... storage charge is anywhere from 3.75 to 3.80v per cell

 

[GadgetGuy]

I too have had problems with swelling Mavic2 batteries. Since I bought my drone a year ago I have used 8 batteries, an 4 of them are swollen and discontinued. There seems to be general consensus that batteries fully charged and subject to high heat is a major trigger for the swelling. So, I would like to describe my 'workflow' to you all and see if you have recommendations for me. I normally fly in the southern US, where it gets hot and humid in the summer. I usually fly for a couple of hours in the afternoon, starting with fully charged batteries and using them until they are about 5% charged. Then I go home and put my 4 batteries on a 4-slot recharger in a room where the temperature is constantly 82F or 28C. I then take them off the recharger when I get up in the morning, so they stay on the recharger about 12-13 hours. Then in the afternoon I go fly again and repeat the cycle. Is the temperature in my room too high? Is 12-13 hours too long? Could my half-hour drive to flight location be the issue? The car can get very hot here, but I turn on the AC full-volume, so the very hot period lasts only a few minutes. Any advice on what I should do differently would be appreciated!

There is nothing different that you should be doing, given your frequency of use. Flying 4 batteries daily requires that they be fully charged at all times. You have had at least 150 charges on each, based upon a year and eight batteries. Only half of them have swollen in the heat and humidity. They are consumables. If DJI will replace them, great. If not, it's just the cost of adventure of a couple of hours of daily flying! Most would kill for that opportunity, so replacing 4 batteries a year is a small price too pay! Enjoy!

 

[Mike4884]

Thank you very much for your advice! I will try these things. It will be a bit cumbersome compared to what I am doing now. I have a 4-battery charger that charges them in sequence, so I can just hook them up and leave them there until they are all charged. To charge them only partially will require a lot of baby-sitting of the batteries one by one. But if that is what it takes not to have them swell.... Does anyone know if there exists a device that charges multiple batteries but stops when they are less than 100%?

You don't really have to worry about that the DJI batteries actually limit themselves so they can never be overcharged I use the RC geeks multi charger and I have been using that brand for the og mavic pro and the mavic 2 zoom and pro 2 that I have never had any problems... I think you had a couple issues with the way you were taking care of them you did get some good advice but the most alarming to me was bringing them down to 5% all the time that is just too low.

 

[GadgetGuy]

but the most alarming to me was bringing them down to 5% all the time that is just too low.

I completely disagree that taking them down to 5% is a problem. Even at well below 0% the M2 batteries are still above 3.5V per cell, which is nowhere near the 3.0V where problems can occur. His own usage over a year, flying 4 batteries daily to 5%, proves that the batteries are not being harmed! Swelling does not harm the batteries per se. They still perform fine. There is a risk of detachment, however, that makes them unsuitable for flight.

 

[parkgt]

Thanks for your advice. Unless there is a device that charges them only to storage level, that would require 'baby-sitting' each battery in turn... I guess it can be done, I just have spend much more time and effort doing that than I am right now. Thanks!

There is such a device and I have been using it for sometime. Storage level from above or below that level, discharge to 0% and charging.

Amazon.com: Hanatora Battery Home Charger & Car Charger for DJI Mavic 2 Zoom/Pro and Remote Controller,5 in 1 Rapid Charging Hub with Charging, Discharging and Storage: Toys & Games

Buy Hanatora Battery Home Charger & Car Charger for DJI Mavic 2 Zoom/Pro and Remote Controller, 5 in 1 Rapid Charging Hub with Charging, Discharging and Storage: Battery Chargers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[parkgt]

The lack of consensus on battery care is amazing! So many opinions, anecdotal observations and little in the way of hard facts.

Most are left with just doing what they feel comfortable with and hoping it works out.

 

[ff22]

The lack of consensus on battery care is amazing! So many opinions, anecdotal observations and little in the way of hard facts.

Most are left with just doing what they feel comfortable with and hoping it works out.

Well, having the batteries be treated like a "pre-parenthood" experiment where you have to nurse, feed and entertain them is crazy. It is like a parent giving a kid a pet on the condition that they handle, care, etc appropriately like another living thing. I also see advice not to charge them when they are too hot. I thought that the batteries (or is it the dji charger) that won't charge if they are too hot anyway.

 

[MAvic_South_Oz]

I thought that the batteries (or is it the dji charger) that won't charge if they are too hot anyway.

Correct, the DJI charger (M1P 12v or mains) won't start until a battery is cooled after flight, I guess also if one was left in the sun before charging.
(Interesting, my 18v tool batteries on their charger also do this, plain Lithium-ion.)
That said, I always let batteries cool down to room / car cabin temp before putting mine on.