Cause of Battery Swelling

[Hans Groover]

I've had my Phantom for almost two years now. I had a third party battery which didn't seem to last long, so I just chalked it up to a bad battery from the local (now out of business) hobby shop. My DJI phantom batteries all seemed to work well, until recently. I noticed all of them seemed to have minor swelling and don't give me more than about 6 minutes of flight time (only timed one of them) whereas before they gave me 12-14 minutes each. My question is, what is causing this swelling? Am I overcharging them? I can only think of one occasion where I might have let one charge overnight. I store them at room temp which is very cool. I do fly them until the Phantom blinks red, so maybe I'm draining them too much? Looking through similar questions I noticed people saying that you should store at 50%. I didn't fly too often over the past few months, could that be the issue? I'm using the charger that came with the Phantom kit, is it possible that it's old or damaged in some way? My most recent batteries are just over a year old now (a year and a month, to be exact) but it seemed to me that the power was starting to weaken a short time back. Sorry for the long thread, trying to add in as many factors as possible. I've been scouring through similar threads and not really finding the same question or issue. Is this just the life of the Lipo batteries? Is there something I can do to prevent this swelling? Again, it's very minor swelling but I do notice a power loss and diminished flight time. I googled the subject but mainly saw posts that you need to get new batteries and stop flying with swelled ones at once. Thanks in advance!

 

[bobmyers]

I've had my Phantom for almost two years now. I had a third party battery which didn't seem to last long, so I just chalked it up to a bad battery from the local (now out of business) hobby shop. My DJI phantom batteries all seemed to work well, until recently. I noticed all of them seemed to have minor swelling and don't give me more than about 6 minutes of flight time (only timed one of them) whereas before they gave me 12-14 minutes each. My question is, what is causing this swelling? Am I overcharging them? I can only think of one occasion where I might have let one charge overnight. I store them at room temp which is very cool. I do fly them until the Phantom blinks red, so maybe I'm draining them too much? Looking through similar questions I noticed people saying that you should store at 50%. I didn't fly too often over the past few months, could that be the issue? I'm using the charger that came with the Phantom kit, is it possible that it's old or damaged in some way? My most recent batteries are just over a year old now (a year and a month, to be exact) but it seemed to me that the power was starting to weaken a short time back. Sorry for the long thread, trying to add in as many factors as possible. I've been scouring through similar threads and not really finding the same question or issue. Is this just the life of the Lipo batteries? Is there something I can do to prevent this swelling? Again, it's very minor swelling but I do notice a power loss and diminished flight time. I googled the subject but mainly saw posts that you need to get new batteries and stop flying with swelled ones at once. Thanks in advance!

Lipos swell if they are run to low -- to many times-- If they are stored with a full charge for extended periods-- over a week, if they become too hot and are discharged rapidly or if they are stored in heat conditions. That has been my experience with lipos I have used in my RC planes in the past. I don't have much experience with the Phantom batteries yet, but being lipos, the chemistry is the same.
When they start swelling, the capacities are reduced significantly.

 

[IflyinWY]

Hello Hans,

Yep, you've got battery issues.
You can get some more info here, click on "Tons of battery information" at the top of the page, for just that. http://www.wynotweb.com/LiPo_Charging.html

Here is something to help you find info within our forum. It's Google Custom Search, and works much better than regular Google.
Enter your text in the middle of the page, not at the top.
https://cse.google.com/cse/publicurl?cx=014775389315664725445:ejku2ysgyhi

Enjoy the show

 

[Melvoid]

Lipos swell if they are run to low -- to many times-- If they are stored with a full charge for extended periods-- over a week, if they become too hot and are discharged rapidly or if they are stored in heat conditions. That has been my experience with lipos I have used in my RC planes in the past. I don't have much experience with the Phantom batteries yet, but being lipos, the chemistry is the same.
When they start swelling, the capacities are reduced significantly.

I've had similar issues... but only with one brand. I have four of the DJI (grey) batteries and two of the Dronefly (black) ones. The latter are the ones swelling. I use them all the same way, so it's odd that only those would swell up like that..

 

[Melvoid]

I just spoke to DroneFly about mine. They're all in the 2-year-old area and he said he was surprised to hear that they're lasting that long. But two of them - the DroneFly brand - are swelling and he said it's time to recycle them. The OEMs seem to be fine.

He mentioned 9 months as a normal life for these things.

 

[bobmyers]

Battery cell manufacture quality varies-- some will last longer than others-- I would assume that DJI has the corner on the best cell manufacturers since their batteries are supposed to be proprietary.

 

[N017RW]

I would assume that DJI has the corner on the best cell manufacturers since their batteries are supposed to be proprietary.

The batteries are proprietary via the 'intelligent' interface (data comm.) so you can't buy form anyone else.
Nothing to do with the quality of the cells themselves.

They are most likely lowest bidder.

 

[bobmyers]

My point is that DJI has probably specified the exact dimensions and specs for their cells-- not considering the just the intelligent interface--but dimensions, exact chemistry and output. As a part of those specs, these cells are probably made specifically for DJI and no one else.