Battery Swelling, How Much is too much?

[Photobobhunt]

Yesterday while making aa modification on my Air 2 s case, I noticed 2 out of 3 of my batteries had very slight swelling. They were the oldest about two years. Both batteries have 52 charge cycles, with even voltage fully charged and with partial discharge. They fit with no restriction, but they failed the spin test.
I've already ordered DJI Factory Reconditioned from a authorized reseller with a 2-year repair or replace warranty.
Most of the YouTube discussion and forum discussion says not to use the swollen batteries.
These fit with no resistance (I have used slightly swollen batteries in cameras as long as they didn't stick for years)
So, this seems to be a short life cycle, is this normal? I have read some suggestions about only charging before the flight and reducing the auto discharge to around 5 days.
Is this good advice?
I was topping off after my flights which may have shortened the life. I usually fly 2 to 3 times a month.
Any comment or suggestions would be appreciated.

 

[StantonZ]

I have read some suggestions about only charging before the flight and reducing the auto discharge to around 5 days.

This is good.

I was topping off after my flights which may have shortened the life. I usually fly 2 to 3 times a month.

This is bad.

 

[MAvic_South_Oz]

I'd recommend keeping a close watch of them during various stages of use / non use.

Eg. check temps by touch when they are auto discharging, when charging (and do this in a safe place / safe process), and right after you land.
They should be warm if flying in reasonable ambient temps, not too hot to the touch.

Also if you have airdata availability to battery health, or even phantomhelp, watch the cell balances during flight, not at time of flight, but occasionally afterwards.
Cell balances should be very close unless flying under increased battery strain, sports mode, or against strong wind, climbing aggressively, etc.

The swelling is a sign the chemicals are breaking down, but you might have some safe life left in them.
How long ? That's the unknown.

 

[spamgnome]

Contact DJI. I had this same issue on my Air 2, and DJI replaced all three batts at no charge to me. I did a handful of flights with the swollen batts, but I found it nerve-wracking. I went so far as to place a velcro strap around the body of the drone just in case it decided to pop out.

 

[bmwbob]

I got over 100 charges before swelling become troublesome. I let them cool off after flight and topped them off.

 

[spsphotos]

Any swelling is bad. Stop using them immediately.

 

[Photobobhunt]

I'd recommend keeping a close watch of them during various stages of use / non use.

Eg. check temps by touch when they are auto discharging, when charging (and do this in a safe place / safe process), and right after you land.
They should be warm if flying in reasonable ambient temps, not too hot to the touch.

Also if you have airdata availability to battery health, or even phantomhelp, watch the cell balances during flight, not at time of flight, but occasionally afterwards.
Cell balances should be very close unless flying under increased battery strain, sports mode, or against strong wind, climbing aggressively, etc.

The swelling is a sign the chemicals are breaking down, but you might have some safe life left in them.
How long ? That's the unknown.

My batteries are not swelling to the point that there is any resistance to making good mechanical connection or electrical contact . I do check the battery health and have noticed that the cells have similar voltage at all stages of discharge. I don't think they would pop out during flight ,,,,but I agree that it's not worth the worry that I could loose a thousand dollar drone over a fifty dollar battery.
I am a a relatively new flyer (2+ years) and a conservative flyer not very adventurous. I only occasionally use sport mode for quick returns.
Great help, thanks a bunch.

 

[Photobobhunt]

I got over 100 charges before swelling become troublesome. I let them cool off after flight and topped them off.

Thats been my policy with camera batteries, so I used it with the drone. But most of the opinions on YouTube recommend letting batteries rest between flights in a discharged state and only charging them prior to the flight.
I expected to get at least 100 charges from a new battery.
Are you implying that slight swelling didn't trouble you or you didn't have swelling?
With my cameras, slight swelling doesn't bother me until the battery won't fall out of the camera without encouragement. But the camera is in my hand, not a mile away.
Thanks for the input.

 

[spsphotos]

My batteries are not swelling to the point that there is any resistance to making good mechanical connection or electrical contact . I do check the battery health and have noticed that the cells have similar voltage at all stages of discharge. I don't think they would pop out during flight ,,,,but I agree that it's not worth the worry that I could loose a thousand dollar drone over a fifty dollar battery.
I am a a relatively new flyer (2+ years) and a conservative flyer not very adventurous. I only occasionally use sport mode for quick returns.
Great help, thanks a bunch.

It does not matter if they still fit and make a connection. Swelling is a sign that the battery is failing. You don't want it to fail in flight suddenly, do you? You don't want it to suddenly become a flaming fireball and fall from the sky. Once you see it swell, no matter HOW little, stop using it. Put it in a safe metal container and dispose of it.

 

[bcfd29]

Just back from a day long seminar on LI battery system fire and explosion hazards that took place in Washington DC Thursday 3.30 (presenters included UL Fire Safety Research Institute, FDNY, DOE, NTSB, and others). Deformation (swelling) of a battery case is the first symptom of impending failure, the device is swelling because the separators that insulate between anode and cathode layers HAS BEEN COMPROMISED. The inside of your battery is made up of tightly rolled layers of chemically coated material (think jelly roll), with a protective layer in between each.

This means that part of the device is already under stress, which ultimately leads to a condition that can cause thermal runaway (direct electrical short circuit between layers). Thermal runaway and catastrophic failure is not predictable and can occur at any time in use or not when a battery has damaged cells/layers.

NOT WORTH THE RISK! STOP using and charging, contact DJI to see if they will replace and dispose of them properly. The amount of energy released during thermal runaway is dependent upon the state of charge (SOC). HIGHER the level of charge, HIGHER the energy released.

You tube is perhaps not the best source of factual knowledge about stuff that can kill you. Just my opinion. Your too important to your family, friends, (and us) to get hurt trying to extend the life of something like a battery. Proper disposal is also important: lost of fires at trash sorting and recycling facilities from peeps who drop their old LI Battery components into the bin or dumpster instead of recycling properly.

 

[bmwbob]

Once they swell to a point they don't fit securely it's time to retire them is my feeling.

 

[Cafguy]

! Trash ! That Battery-- You not only risk losing your drone ,that bad battery could start a FIRE!! best to throw it in a bucket of salt water for a day and then into the trash

 

[Drbobk]

Once they swell to a point they don't fit securely it's time to retire them is my feeling.

Seems to me that once it is swollen, you are not going to know how it reacts to use in the drone, and with heating, and if the bottom swells enough, it will pop the battery out (up) and down comes the drone. I have one that I use only for static purposes, like checking software settings, unlocking licenses, etc. I'm afraid to charge it.

 

[Photobobhunt]

Seems to me that once it is swollen, you are not going to know how it reacts to use in the drone, and with heating, and if the bottom swells enough, it will pop the battery out (up) and down comes the drone. I have one that I use only for static purposes, like checking software settings, unlocking licenses, etc. I'm afraid to charge it.

After all of the replies to this thread and other research, I took all of my LI batteries that had any swelling to Home Depot for disposal . That included a few used in my digital cameras.

 

[kenjancef]

Seems to me that once it is swollen, you are not going to know how it reacts to use in the drone, and with heating, and if the bottom swells enough, it will pop the battery out (up) and down comes the drone. I have one that I use only for static purposes, like checking software settings, unlocking licenses, etc. I'm afraid to charge it.

I have a swelled battery for that purpose as well, but I do charge it, but always when I am around to keep an eye on it, like watching TV or such. And only use it for config or firmware updates.

 

[Drbobk]

! Trash ! That Battery-- You not only risk losing your drone ,that bad battery could start a FIRE!! best to throw it in a bucket of salt water for a day and then into the trash

Even better, take it to a Lithium Ion recycling center, like Lowes or Home Depot.

 

[Capt. Quirk]

Even better, take it to a Lithium Ion recycling center, like Lowes or Home Depot.

I'm thinking of disposing of my Tesla at Home Depot as well.

 

[Aairon]

"You don't want it to suddenly become a flaming fireball and fall from the sky." :-O