Battery got wet.

[MileHighSi]

I was flying on a beach recently, having used my carry case (the one which comes with the fly more package) as a take-off platform. I regularly do this on uneven or dusty (or in this case sandy) surfaces. However, it seems that this time I'd been a bit careless, as a wave came right up the shore and the lower part of the bag became submerged. Unfortunately, as you'll have guessed from the title, my spare battery was in there.

The next day I tried the battery and although all four lights showed on the back, the drone didn't turn on. The next day, I gave it a full charge (it was showing 4 lights but w/e) and tried again. No such luck. I decided to leave it alone until I was back home 2 weeks later. It was a pain just having one battery – I'm not sure how anyone does it tbh..

Well I'm back home now and the battery is working again. The drone turns on and I've taken it up a few ft just to test.

My question is: despite seemingly working as normal, is the battery safe to fly with?

 

[AeroMirage]

I wouldn't trust it. Salt water reeks havoc on electronics. Even though it is working now, you have no way of knowing when the corrosion that is happening inside it will make it quit, (Fall out of sky....) or worse yet, explode or catch fire when charging.

 

[MileHighSi]

I wouldn't trust it. Salt water reeks havoc on electronics. Even though it is working now, you have no way of knowing when the corrosion that is happening inside it will make it quit, (Fall out of sky....) or worse yet, explode or catch fire when charging.

Thanks for the reply. How long (I know, there's no definitive answer but – at a maximum) would a person wait before determining whether corrosion has occurred/won't occur? I'm not in to binning potentially working gear.

 

[AeroMirage]

The fact that it wouldn't work right after it got wet shows that it did get wet internally. Look at the pins for whitish corrosion.
Also, I would charge it fully and look at the screen report of condition on both batteries and see how they compare.
Look for cell imbalance and how close it is to total capacity.


Personally, I would cut my losses and trash it. Better than losing the whole bird.

 

[MileHighSi]

Thanks again for the informative reply.

I've just had a quick look. Screenshot attached. I'll charge both fully and compare later.

Whilst I was at it, I took the drone + suspect battery for a little flight. Again, everything seemed okay. I took it a little higher (20ft or so), performed all controls and even threw it in to Sport mode for a second. Everything looking good. Landed fine, too.

I'm also attaching a photo of my two batteries. I've put a sticker on the suspect one so I can differentiate. To my eye, there's not much difference between the two (even less so on the other side so I won't waste attaching a photo of that). The gold plates aren't particularly glossy on either battery, but I suspect this is common and nothing to do with the salt water.

I don't mean to fight against replacing the battery, but I'd like to be absolutely certain before throwing it. Not just for the cost but for the environment.

 

[MileHighSi]

Sorry, you said pins. Here's a photo of the suspect battery's pins. Again, nothing too telling here?

 

[AeroMirage]

That is surprising.
But the 4 square contacts on the other side of both don't look too good.

 

[The Editor]

Thanks for the reply. How long (I know, there's no definitive answer but – at a maximum) would a person wait before determining whether corrosion has occurred/won't occur? I'm not in to binning potentially working gear.

If seawater has touched it - corrosion has already started. Dispose of it, its finished.

Incidentally, why would you take off from the bag with the associated sand and grit potential of being kicked up into the motors when you can take off from your hand with two taps of the battery button?

 

[MileHighSi]

So how long until I can say for sure whether it's fubar or, actually, completely fine?

As for ground take offs. I like to do a quick preflight check on the app first and it's a nuisance to hold both the controller and the bird. I also like to start the rotors spinning first, before taking off.. just to make sure all four are firing nicely. Should I have developed a propellor or motor issue I'd prefer to find out on the ground. Anyway, I digress.

 

[aviscomi]

I personally would not use the battery. The risk outweighs the rewards $45 battery vs. $500 drone

 

[Kanehi]

Putting the battery in rice (not cooked) helps is absorbing moisture. Did you shake the battery after it got wet as to get rid of excess water? If you let it sit out to dry corrosion would've taken place. Sometimes batteries are well sealed and only the contacts are exposed which is usually corrosion resistant ie gold/gold plated. I don't know if DJI uses gold plated contacts or copper. Only time will tell if the battery is in fact affected. If it charges well multiple times it's probably okay.

 

[The Editor]

Putting the battery in rice (not cooked) helps is absorbing moisture. Did you shake the battery after it got wet as to get rid of excess water? If you let it sit out to dry corrosion would've taken place. Sometimes batteries are well sealed and only the contacts are exposed which is usually corrosion resistant ie gold/gold plated. I don't know if DJI uses gold plated contacts or copper. Only time will tell if the battery is in fact affected. If it charges well multiple times it's probably okay.

No it doesn't
Don't Put Your Device in Rice. Here's Why...

 

[Kanehi]

No it doesn't
Don't Put Your Device in Rice. Here's Why...

For the regular Joe they're not very keen in opening electronics. Supposedly the item should be rinsed in plain water as to displace the salt water inside, shake off the excess water and the place in rice to absorb the remaining moisture and leave in for three days or more. Actually a desiccant would be better than rice but then again who has access to it readily. Sometimes it'll work sometimes not but it wouldn't hurt trying it. 90% isopropyl alcohol still contains 10% water. A better way is to use distilled water to rinse with as it doesn't contain mineral contaminants.

 

[The Editor]

For the regular Joe they're not very keen in opening electronics. Supposedly the item should be rinsed in plain water as to displace the salt water inside, shake off the excess water and the place in rice to absorb the remaining moisture and leave in for three days or more. Actually a desiccant would be better than rice but then again who has access to it readily. Sometimes it'll work sometimes not but it wouldn't hurt trying it. 90% isopropyl alcohol still contains 10% water. A better way is to use distilled water to rinse with as it doesn't contain mineral contaminants.

An even better way is to carefully dispose of the lipo pack, then purchase a new one and fly confidently in the knowledge that your new battery won't suddenly fail on you mid flight due to creeping corrosion unseen internally.
It just isn't worth it.

 

[MileHighSi]

No it doesn't
Don't Put Your Device in Rice. Here's Why...

Your link is broken. I've riced my fair share of wet electronic items with success in both the short and long term..

 

[msinger]

Your link is broken

Here's a working link:
Don't Put Your Device in Rice. Here's Why...

 

[MileHighSi]

An even better way is to carefully dispose of the lipo pack, then purchase a new one and fly confidently in the knowledge that your new battery won't suddenly fail on you mid flight due to creeping corrosion unseen internally.
It just isn't worth it.

You're keen to have the definitive say on this matter, which is fine if you're an expert on the matter. In that case, could you please let me know how long it would take (maximum) to discern whether or not corrosion has/will-definitely take place? There must be a max. I have no problem getting another battery, but if I can keep the one which got wet (but works) as an emergency third (or even forth) then I would.

 

[The Editor]

You're keen to have the definitive say on this matter, which is fine if you're an expert on the matter. In that case, could you please let me know how long it would take (maximum) to discern whether or not corrosion has/will-definitely take place? There must be a max. I have no problem getting another battery, but if I can keep the one which got wet (but works) as an emergency third (or even forth) then I would.

I operate commercially and therefore minimise risk as much as possible. A device (in this case the lipo pack) that has been subject to a salt water environment is an unknown variable and therefore IMO should be removed from service.

 

[MileHighSi]

I operate commercially and therefore minimise risk as much as possible. A device (in this case the lipo pack) that has been subject to a salt water environment is an unknown variable and therefore IMO should be removed from service.

You made that clear buddy don't worry. My question was how long, should I continue to test it safely, would be long enough to say 'Great, it's definitely fine!'? I mean, there must be a realistic maximum time it'd take to corrode?

 

[The Editor]

You made that clear buddy don't worry. My question was how long, should I continue to test it safely, would be long enough to say 'Great, it's definitely fine!'? I mean, there must be a realistic maximum time it'd take to corrode?

Yes - until it drops out of the sky.
Fill your boots - go fly.