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Slightly Swollen EVO II Pro Battery (Advise Please)

CREVO2PRO

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Hello Pilots,

I just noticed after my flight today that one of my EVO II Pro batteries is slightly swollen. I know many of you have probably had the same issue.
Looking for some best practices in this situation. The battery performed as normal during the flight.
Is it safe to use as long as it does not get worse?
It is not getting hotter than normal during flight or after it is removed.
There is some slight resistance when inserting but it fits and snaps in without much pressure
Is it best to retire the battery now or keep an eye on things.?


Thanks in advance for any advice
Charles
 
How many cycles does it have on it? I usually get somewhere between 35 to 40 before I start seeing degradation in performance. If your battery has upwards of 25 to 30 cycles I would consider getting rid of it. Simply let it self discharged until it's 1/3 to 1/2.
When I retired my first three batteries I simply put them in a bucket of warm salt water for 3 or 4 days after letting themselves discharge, then simply throw them in the trash like you would any other battery. If you don't feel comfortable doing that then take them to a place that disposes of used batteries.
 
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How many cycles does it have on it? I usually get somewhere between 35 to 40 before I start seeing degradation in performance. If your battery has upwards of 25 to 30 cycles I would consider getting rid of it. Simply let it self discharged until it's 1/3 to 1/2.
When I retired my first three batteries I simply put them in a bucket of warm salt water for 3 or 4 days after letting themselves discharge, then simply throw them in the trash like you would any other battery. If you don't feel comfortable doing that then take them to a place that disposes of used batteries.

Hi, I'll have to double-check on the cycles not sure but guessing at least 20. Thanks for your thoughts,
 
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Wow, that's a huge investment in batteries. Not looking forward to the cost of another one darn.

Yes I have around 20k in Autel products.
I have a E2P V1, a RTK V3 and a 640T V3. All of them are rugged bundle As well as lens filters, lots of 128gb SD cards, tablet holder ect.. ect...

If you can do with just 1or 2 then wait till you can afford it financially.
I fly a lot of missions so I need several batteries.
 
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Hello Pilots,

I just noticed after my flight today that one of my EVO II Pro batteries is slightly swollen. I know many of you have probably had the same issue.
Looking for some best practices in this situation. The battery performed as normal during the flight.
Is it safe to use as long as it does not get worse?
It is not getting hotter than normal during flight or after it is removed.
There is some slight resistance when inserting but it fits and snaps in without much pressure
Is it best to retire the battery now or keep an eye on things.?


Thanks in advance for any advice
Charles

I 100% agree with @MNT DRONE SOLUTIONS swelling is your first warning to immediately stop using the battery. 32 cycles seems pretty low, typically the rule of thumb for drone LiPo batteries is 2yrs or 100 cycles (whichever comes first), is the battery also around 2yrs old? I am now at the 2.5yr mark with my original 4 batteries and every single one still performs like the day I bought the drone, I will need to check the cycle counts tomorrow but I would estimate them all to be over the 32 cycle mark.

But I also do everything that I recommend here for longevity (never drop them if at all possible, manually discharge to around the 50% mark, if fully discharged after use then recharge to around the 50% mark, never recharge while they are hot, do not leave them stored in your hot car any longer than necessary, etc).
 
I 100% agree with @MNT DRONE SOLUTIONS swelling is your first warning to immediately stop using the battery. 32 cycles seems pretty low, typically the rule of thumb for drone LiPo batteries is 2yrs or 100 cycles (whichever comes first), is the battery also around 2yrs old? I am now at the 2.5yr mark with my original 4 batteries and every single one still performs like the day I bought the drone, I will need to check the cycle counts tomorrow but I would estimate them all to be over the 32 cycle mark.

But I also do everything that I recommend here for longevity (never drop them if at all possible, manually discharge to around the 50% mark, if fully discharged after use then recharge to around the 50% mark, never recharge while they are hot, do not leave them stored in your hot car any longer than necessary, etc).

The swollen battery I'm speaking about is around two years old and performs like new actually both batteries do. I'm going to keep my eye on it a look for a new replacement
 
Yea just think about it twice. Any indication of a battery failing any time soon is a reason to stop using it for flight. Loss of the aircraft or injuring someone in an accident is worse than getting a new battery. You don’t drive a car on tires that are worn out or show cracks in the rubber, do you?

A flying drone is not an electrical drill or a laptop that you can try to push until it doesn’t work at all.

Indications of a Li-Po battery failing are:

A. big differences in voltage between Li-Po cells. Check battery management in the app.

B. Sudden drops in remaining power, let’s say for example from 80% to 40% in just a minute or two.

C. Swollen cells or bulging enclosure of the cells.

D. Unusual high temperatures, to even seeing signs of it melting plastic.

E. No longer being able to charge the battery to full. Or charging takes double the time than it used to take.

F: Software indication of erratic battery behavior.

Or finally just out of precaution if it’s too old. For this reason just write the date of first use on your batteries if you own multiple. And keep track of the loading cycles and actual times it was used. Having a kind of log on paper or note on your phone can be useful.
 
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The swollen battery I'm speaking about is around two years old and performs like new actually both batteries do. I'm going to keep my eye on it a look for a new replacement

That is about right then, no way would I take off ever again with that battery. When LiPo batteries start to fail from age they give you warnings (decreased flight times, swelling, battery errors) vs. when they are too cold at which point you typically get no warning and they just fall from the sky. IMO the swelling could be your only warning or it might give you additional warnings, but why risk a $2K drone or worse damage to property, people or a battery fire over a $200 battery like @uas_gian said.

When it comes to swollen batteries there really isn't anything to keep an eye on, the battery is guaranteed to fail no matter how well it is working; the only question is if it will fail in the sky or before takeoff.
 
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You are asking the $64,000 question! I have retired four batteries and none had more that 80 cycles. Autel told me they are good for, on average, one year. The signal I use is when I look through the vents on the side of the battery and don't see any light (coming between the three internal cells). It is very frustrating to have to put a battery down. I wish the technology could help us know for sure when a battery becomes a risk to fly.
 
You are asking the $64,000 question! I have retired four batteries and none had more that 80 cycles. Autel told me they are good for, on average, one year. The signal I use is when I look through the vents on the side of the battery and don't see any light (coming between the three internal cells). It is very frustrating to have to put a battery down. I wish the technology could help us know for sure when a battery becomes a risk to fly.
@AirStag. Now I am curious to hear in what year(s) you bought those 4 drone batteries. I am noticing big differences in age and battery performance between different batches. Good to know the "not more than 80 loading cycles" are to be taken into my new expectations. This is quite a low number. My laptop from 2012 still has it's original battery and works amazingly well today (with 609 loading cycles), meanwhile my laptop built 2018 already received a new battery. Both exist out of LiPo cells like our drones do. So the average quality standards for Li-Po cells in general seem to have been lowered in the past decade.

I suspect Autel has also switched suppliers that produce those cells for their products. The changes from V1 to V2, then introduction of Nano and Light and now Evo 2 V3 show how quickly they switch between suppliers of internal hardware, hence I say they probably also do this for all other components. The user reports about bad batteries being shipped with the Evo Light and Nano seem to pop up more often than before. Not a good development regarding the future.
 
@AirStag. Now I am curious to hear in what year(s) you bought those 4 drone batteries. I am noticing big differences in age and battery performance between different batches. Good to know the "not more than 80 loading cycles" are to be taken into my new expectations. This is quite a low number. My laptop from 2012 still has it's original battery and works amazingly well today (with 609 loading cycles), meanwhile my laptop built 2018 already received a new battery. Both exist out of LiPo cells like our drones do. So the average quality standards for Li-Po cells in general seem to have been lowered in the past decade.

I suspect Autel has also switched suppliers that produce those cells for their products. The changes from V1 to V2, then introduction of Nano and Light and now Evo 2 V3 show how quickly they switch between suppliers of internal hardware, hence I say they probably also do this for all other components. The user reports about bad batteries being shipped with the Evo Light and Nano seem to pop up more often than before. Not a good development regarding the future.
Those four batteries were purchased with drone kits in June 2020 and February 2021. I beleive I retired them in March this year.
I thought I read somewhere that these batteries should be good for ~200 cycles, but I can't find that now.
Regardless, I am disappointed.
 
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Started with 7 batteries March 2021. I only have 2 working non-crit batteries that are still air-worthy. The 5 that crit after take some a swollen and hard to slide in. 1 or 2 look just fine no swelling, all have around 60 cycles. Funny thing is 1 of my 2 batteries that still work one of them slid out of my drone 40' above water. Only one side battery latched on the drone so I never got the check battery connection message. Soon as I took off I went up about 40' went out over the water 20' out or so and as soon as I let off the forward stick the drone leaned backwards to slow down and that's when I heard the motors stop instantly and 1 sec later I heard a loud smack in the water. Drone was 4' under water with the battery about 3' behind it. Drone was under water for about 3mins before I got to it.Went home and took everything apart blew all the water out of the drone and battery. The only thing that stayed dry that I was worried the most about was my dual flir boson. I took it apart and it was all dry inside. I had the drone going the next day and that battery is still running good. That incident happend July 3rd of '21. I got it back in the air right at dark the next for the 4th.
 

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