Swelling batteries

[hewo]

Maybe stressors count more?
Hotrodding always destroys, right?
That's why driving like gramma prolongs longevity.

Most photographers do not press hard on the drone. They do the opposite. Yet they still experience bulging.

It either stems from battery care processes and or factory qaqc, latter being remote.

During charge up, my batteries are never warm. But the charger gets warm thru out charge up. Same with car charger, batteries never are warm but car charger thru out charge up is warm.

So the only warm, rather warmer than warm, occurs by flying. Is there a thermocouple embedded for sensing troubles? The apk displays overall battery temperature.

 

[runeOfRune]

Do NOT partially charge the battery for storage! If you only charge it to "50%", you will probably end up below the optimum storage voltage. The batteries self discharge to below 65% but they will NOT have discharge rate of your typical 65%-after-flight battery - that's why the app warns you.

Since those batteries already have a balancer, ALWAYS charge them fully and let them discharge on their own as needed. Otherwise for non-smart batteries, use your balancing charger in STORAGE mode.

Do NOT fly on a battery that's been in storage mode, always fully charge it first.

 

[Bill Ludwig]

With the Arizona summer heat, I put my batteries in a cooler during transport, take them out to fly, then put them back in the cooler upon return. Nice cool operating temperatures that way and no worries about overheating my batteries. Anyone else doing that?

 

[hewo]

Do NOT partially charge the battery for storage! If you only charge it to "50%", you will probably end up below the optimum storage voltage. The batteries self discharge to below 65% but they will NOT have discharge rate of your typical 65%-after-flight battery - that's why the app warns you.

Since those batteries already have a balancer, ALWAYS charge them fully and let them discharge on their own as needed. Otherwise for non-smart batteries, use your balancing charger in STORAGE mode.

Do NOT fly on a battery that's been in storage mode, always fully charge it first.

Information is invaluable.
That will avert incident.
Too bad the documentation did not explicit exact invaluable information.
Summer season incident statistics?

 

[thatswedishguy]

Do NOT partially charge the battery for storage! If you only charge it to "50%", you will probably end up below the optimum storage voltage. The batteries self discharge to below 65% but they will NOT have discharge rate of your typical 65%-after-flight battery - that's why the app warns you.

Since those batteries already have a balancer, ALWAYS charge them fully and let them discharge on their own as needed. Otherwise for non-smart batteries, use your balancing charger in STORAGE mode.

Do NOT fly on a battery that's been in storage mode, always fully charge it first.

Sorry, but that's not good advice. 10 days to storage is way too long. Making that a practice is begging for swelling. General consensus is no more than a day at full charge. I'm not sure about the exact storage level of these high voltage lithium polymer batteries, but 50% should be safe.

I usually accomplish this in one of two ways. Either fly them down to 50% for short term storage (a couple of days) in which case they will be slightly unbalanced, but it doesn't matter for a couple of days of storage, or I fly them down to ~25% and charge them back up to 50% (takes about 16 minutes). This way they never stay too high or low for more than a day, and swelling should be avoided.

I don't know why DJI feel that 10 days of full charge and then an additional 3-4 days is a good way to do it, but it's really not.

 

[Simk1n]

Sorry, but that's not good advice. 10 days to storage is way too long. Making that a practice is begging for swelling. General consensus is no more than a day at full charge. I'm not sure about the exact storage level of these high voltage lithium polymer batteries, but 50% should be safe.

I usually accomplish this in one of two ways. Either fly them down to 50% for short term storage (a couple of days) in which case they will be slightly unbalanced, but it doesn't matter for a couple of days of storage, or I fly them down to ~25% and charge them back up to 50% (takes about 16 minutes). This way they never stay too high or low for more than a day, and swelling should be avoided.

I don't know why DJI feel that 10 days of full charge and then an additional 3-4 days is a good way to do it, but it's really not.

10 days is what DJI says/programmed so that should be safe.

Listening to random guys at forums is not a good advise, you will soon have 15 different opinions from people who think they are experts. Sorry, but listen to the manufacter, period.

 

[thatswedishguy]

10 days is what DJI says/programmed so that should be safe.

Listening to random guys at forums is not a good advise, you will soon have 15 different opinions from people who think they are experts. Sorry, but listen to the manufacter, period.

Except that it's well known in the RC hobby world that lithium batteries should not be left fully charged for more than a day. Ask any RC hobbyist that has been doing it for a while.

I don't trust DJI to have battery longevity as the number one priority with their short battery warranty. They'll be glad to sell more batteries for sure. I go by the collective years of experience of the RC community with the knowledge proven to prolong battery longevity and prevent swelling. I don't know what DJI was thinking with 10 days until it even begins to discharge but unless they have made a breakthrough in battery technology it's not sufficient. I don't care what they say.

 

[Simk1n]

Each to their own.

10 days is perfectly fine, and people have been using this method for years with their LIPO's on their DJI products.

I have 12 batteries across 3 drones, no problems.

 

[globetrotterdrone]

I was just to order a multi charger with the possibility only to load up to 65 % ... now I am not sure, because having my drone now for 2 weeks, I thought charging up from about 15 - 20 % to 50 % (when the 3rd ring segment starts flasing) is a safe method to store the batteries.

It's quite a pain, with the DJI Hub or individually to control every time.
So, now I am stuck: fully charge and wait 14 days for the safe amount to store or only charge up to 50 - 65 % and leave them ...

I am not sure, which is the best alternative now for longevity... I can follow both arguments from manufacturer's and user's side ... ??
I really would like to have the possibility like with the Mavic Pro to lower the days to discharge.

 

[Jet skier]

I was just to order a multi charger with the possibility only to load up to 65 % ... now I am not sure, because having my drone now for 2 weeks, I thought charging up from about 15 - 20 % to 50 % (when the 3rd ring segment starts flasing) is a safe method to store the batteries.

It's quite a pain, with the DJI Hub or individually to control every time.
So, now I am stuck: fully charge and wait 14 days for the safe amount to store or only charge up to 50 - 65 % and leave them ...

I am not sure, which is the best alternative now for longevity... I can follow both arguments from manufacturer's and user's side ... ?[emoji52]
I really would like to have the possibility like with the Mavic Pro to lower the days to discharge.

Everybody is overthinking it simply follow the manufacturer instructions.I understand their warrantee issue because you can’t ship a faulty battery for safety reasons

 

[gnirtS]

Following the instructions has resulted in several of us having unusable swollen batteries 7-8 months after purchase with very few cycles.
That said, im fairly sure its caused by humidity and temperature whilst in flight as opposed to chargin or storage.

 

[globetrotterdrone]

Thank you!
So what is best practice ... the manual is not quite clear on this point to either charge to some percentage or to fully charge and later discharge?



vs



Source: https://dl.djicdn.com/downloads/Mav...igent_Flight_Battery_Safety_Guidelines_EN.pdf

 

[gnirtS]

Just charge it to max 60% or so. Avoids a heating charge/discharge cycle if you know you're not going to be using it.

 

[BigAl07]

IMHO 10 days is about 2x as long as you should leave a battery at FULL charge. I can tell you that after years of practice and handling probably a total of 40 batteries "currently" that a constant 10day FULL charge will result in reduced life/punch for our SMART batteries. We use a 5-day routine and if the batteries are not "pushed" they can have hundreds of charges with no puffing. After a couple hundred they still get "soft" on the punch out but they are still well within allowable levels.

I can show you 3 of 6 Mavic Platinum batteries that are less than 8 months old that are PUFFING! After looking into it a little more the "operator" is using the "DJI Suggestion" of 10 days to "start" the discharge. If you only fly a few times a month you could just about have your batteries in constant FULL charge state.

Keep in mind that a LARGE portion of "Sales" for our sUAS come in the form of BATTERY PURCHASES so longevity of the batteries may not be DJI's top priority for uses.

 

[globetrotterdrone]

Well, I get that a 10 day may be an acceptable standard for DJI to probably sell a bit more batteries ... I wonder why we are not able to change that like the generation before? For users, who don't want to hassle with all these, 10 days is still a safe time, but if you really want to max lifetime, I would be much more pleased 3 - 5 days.

 

[tbrim]

About a month ago I experienced a crash of my Mavic 2 where the motors just seemed to shutoff mid-flight without warning. Review of data logs by members of MavicPilots.com indicated that the problems seemed to be battery related.
Yesterday I tried to fly while up here in Colorado on vacation near a inactive airport. DJI Go4 still thought it was active and displayed a message window that covered most of the display screen shortly after I lifted off the drone warning me that I was in a restricted area and provided a prompt to acknowledge that I was responsible for flying there. The "Yes" prompt was greyed out and it never gave me an opportunity to accept and continue to fly. Since I couldn't see anything on the display screen I just landed and put my drone away and moved on to another location.

I was planning on capturing some aerial footage the next day so when I got back to where I was staying I took my drone out of the bag and was surprised to see that the battery appeared to no longer be seated properly in the drone and the latch on one side was not engaged. It was not in this condition when I was flying nor when I put it back in the bag. I took the battery out and looked at the bottom side and found it to be swollen. I checked the other three batteries in my bag and two of the others also showed the very same swelling. The fourth battery did not exhibit this - it was the brand new one that DJI sent me along with the new drone I got from Refresh. (It has only been recharged 4 times.) The other batteries have been used extensively since I obtained the drone and have been charged 80-90 times each. (They no longer fit in the drone, so I can't check their stats.)

 

[Bill Ludwig]

It would be really interesting to load your flights into AirData, and take a look at the battery temps during the course of the battery’s life. I’m guessing overheating either in the drone, or in storage.

 

[hewo]

It is hard to study this incident that brought manifestations of warranty claim of swollen batteries, being june is so recent a forum debut with about half life remaining on longevity for rated 200hot else 300cold recharge cycles of the battery.
possibly post incident owner neglected thorough forensic exam why the halt of flight, and resurrect.
suspicion is hefty charge displacement, the movement of charge, which is ampere current, but how & why did it occur? one or the other or both had to occur, runaway current demand else temperature escalate.
these batteries cost!

 

[anim8r]

... I’ve been taking care to remove my batteries immediately after flight and keeping them out of the case to maximize cooling...

I fully agree with this practice, I was plopping my batteries into the case right after use and one of my buddies gave me a "whoa there" lol. It makes sense to NOT put a hot battery into a suffocating foam cutout. Since then, they stay out in the open and cool in the shade.

 

[hewo]

immediately landing, powerdown, unbuckle battery, compress cpu battery side onto cheek feel hot temperature conducted out from it and place upright on flat surface, usually the launch area soil
after three tandem flights with three batteries only the final battery has to cooldown, about fifteen minutes
then charge em all for tomorrow

the batteries stay cold always during charge by line or by automobile so it means the chargers are perfect, and so are the batteries giving full durate