open mavic 2 battery

[aPpYe]

I haven't found any tutorials on this anywhere... I (stupidly) crashed my Mavic 2 in a river a couple of weeks ago. I have the refresh thing from DJI and received a replacement drone and battery within a week. This leaves me with the battery that got wet. It charges just fine. I even put it in the new drone and flew around a bit, mostly hovering about 2 feet over some long grass to be safe, but it worked. It takes and holds a charge and seems to work just as fine. I was thinking that before I trust it, I want to open the battery up to see if there is any corrosion (that telltale blue powder) anywhere on the electronics. If it all looks good, I got a free battery out of the deal!

Any tutorials on how to open up the battery without breaking anything? I suppose a couple broken tabs aren't a huge deal, and there's always epoxy ...

 

[Just_nick]

Pretty sure you cannot. That being said, you really want to risk a $1,400 drone over a $100 battery?

 

[Kilrah]

The case is glued in some places, you can't open it non-destructively.

 

[Former Member]

Ive tried before, but unless you are very careful, its like letting the genie out of the bottle.

 

[aPpYe]

Well, I suppose I can cut it open? Have you any pictures of the "disassembled" battery, so I know the parts to avoid cutting into any wires or boards? My thought is that since the battery was not completely submerged, the electronics may have avoided the water. It was still powered on when I retrieved it.

If I can get it open, and there is no blue powder/corrosion, then yes, I will trust my $1400 drone with a $100 battery and $5 epoxy!

 

[Former Member]

First, call the fire department before you begin. lol

Try to pry it up under the latches. They use very strong glue, so the shell will probably be contorted after youre done.

Dont cut anywhere near the power button because of the low voltage wires powering the buttons' LED.

 

[Canuk]

I had a phantom 2 battery that puffed up and was a bugger to install and remove from the bird so I decided to test how bad a lipo fire would be . I placed it in the middle of my yard and stabbed it with a sharpened rod . I would not want a lipo battery to fail inside a house . Flames were very small but the amount of smoke was crazy from one drone battery . There was the same amount of smoke as if I was burning a tire . Crazy . My battery’s don’t live in my house anymore. They are in a ammo can and in the garage . My guess is the smoke would be very toxic .

 

[JRT]

This is just a dumb thread. Just-nick is right. You already made the mistake of flying the aircraft into water... how will you feel when the battery blows up in your face... or worse... when it fails and crashes down from the sky? This hobby is not for some people... please refrain from dumb behavior and starting stupid threads. A wet battery is a damaged battery. Dispose of it properly please. Don’t risk an accident or the drone to save a $100. This is the dumbest sh@t I have ever read.

 

[Canuk]

If you are getting this worked up maybe you need a timeout . He came on here and was looking for people’s point
Of view . There is nothing that gets my blood pressure going *** someone going on and on like they are god . 99 times out of a 100 that crap would not happen face to face .

Why not a simple ( bad idea as you don’t want to risk the danger of a how to control battery for a crashing drone .

If someone don’t like a thread MOVE ON

 

[fstop.labs]

The battery unit is glued and tricky to open - the easiest way is to use an ultrasonic knife to cut around it, we have one and it cuts through plastic like butter. Otherwise you can heat up an exacto knife and slowly cut around it. The cells are sealed and will be fine, the electronics can be cleaned if there is any corrosion.

One of these:
https://www.amazon.com/Honda-Electronics-ultrasonic-cutter-USW-334/dp/B005QFWCQO/

 

[aPpYe]

This is just a dumb thread ... This is the dumbest sh@t I have ever read.

My humblest apologies. I will go cry now, feeling ashamed, having been properly lambasted by my intellectual superior.

To answer your questions, if it blows up in my face, I am guessing I might feel pain, perhaps from a burn. If it falls from the sky, I will feel sad.

Otherwise you can heat up an exacto knife and slowly cut around it.

The hot knife trick! I had forgotten about that... I will likely do that. I was thinking of cutting through with a rotary tool, but the hot knife trick might be a better idea. I think I'll pass on the $324 knife!

 

[Chopstix Kid]

its like letting the genie out of the bottle.

I had a boyhood crush on Barbara Eden

 

[Former Member]

I had a boyhood crush on Barbara Eden

I still have one on Jeannie (And Farrah, and Cheryl Ladd, and ....)

 

[Chopstix Kid]

I still have one Jeannie (And Farrah, and Cheryl Ladd, and ....)

.... and Jaclyn Smith and Heather Locklear. The late 70s and early 80s were good times.

 

[aPpYe]

Jeannie! I can remember watching that back to back with Bewitched when I was a kid during some syndication run at some point.

 

[Deadleg]

I haven't found any tutorials on this anywhere... I (stupidly) crashed my Mavic 2 in a river a couple of weeks ago. I have the refresh thing from DJI and received a replacement drone and battery within a week. This leaves me with the battery that got wet. It charges just fine. I even put it in the new drone and flew around a bit, mostly hovering about 2 feet over some long grass to be safe, but it worked. It takes and holds a charge and seems to work just as fine. I was thinking that before I trust it, I want to open the battery up to see if there is any corrosion (that telltale blue powder) anywhere on the electronics. If it all looks good, I got a free battery out of the deal!

Any tutorials on how to open up the battery without breaking anything? I suppose a couple broken tabs aren't a huge deal, and there's always epoxy ...

I'm with you my friend. I had water damage and I'm sure parts of the battery can be salvaged. I have already dismantled 2 Mavic 1 batteries and rebuilt them into a 3s2p configuration. Works really well.

I have the two halves of the shell open, but it's difficult to separate the top and bottom of the cells from the case. Will have to carefully cut away more of the plastic to see what's holding the cells. I'll let you know when I've made more progress. The ultimate aim is to construct a long-distance battery as for the Mavic 1.

 

[kencox]

Discovering the contents by opening a battery is not worth losing your eyesight over.

Recycle it and enjoy a flight instead.

 

[Deadleg]

Right, the battery has been dismantled (and I can still see!) . . this is what I did:

Shell cracked with plastic spudger and broad-blade screwdriver. The shell is glued more firmly than Mav1 battery and it is difficult not to damage the case. The top and bottom halves are glued to the top and bottom of the battery, (unlike Mav1 battery which can be removed from shell easily), so proceed with care or you may break the cell connections. In the end I cut off the back of the upper shell with dremel disk (with extreem care not to go deep and cut the cell!). Then I could get the spudger in and prise off the top. The start button and board (designated LED board by Dji) are also stuck to the top of the battery and have to be carefully prised off. The button assembly then falls away.

The LED board is connected to the BMS board by a thin strip connector. It also has 2 more connections going to microswitches on either side of the shell, and these switches swith the battery off when the side latch buttones are pressed. This safety measure is new to the Mav 2. I just cut these waires, and I will solder tham together at a later stage.

Taking out the BMS board is a bit tricky because the small screws which hold the board to the shell are glued it. However, with enough force (I used a mole wrench on the screwdriver) they can be removed. Go round the multi-pin connector with a modelling knife to remove more glue, and the BMS board should start to come out. It is connected to the battery board by 2 short pòwer cables and the balance cable. Cut the power cables (one at a time!) and then unplug the balance cable from the BMS board. It will stay connected to the battery board. Pull out the thermistor cable from the battery, and then the BMS board can be removed. I left the BMS and LED boards connected because the connector is glued in place. It should be possible to pick away the glue and disconnect if necessary.

The battery, which went for a swim in my semi-salty pool, is still almost fully charged, so thankfully the cells are not damaged. There is a fair bit of corrosion on the boards, but this should clean off. I image that the BMS board no longer works . . we shall see.

 

[Deadleg]

I forgot to mention the most difficult problem of all! I could not remove the cells from the bottom shell, because the bottom cell is stuck firmly to the shell. I tried taking off one end of the shell and using the spudger to pry the cell off, but it was stuck firm, and there was a risk of damaging the cell. In the end I carefully cut around the bottom plate of the shell, and that plate will probably have to remain stuck to the bottom cell . . I dare not try to unstick it. This is not a huge problem, unless you are trying to reduce weight to a minimum, and it does add strength to the assembly.

 

[Jet-Pack-Jesus]

Man great info. I have seen the extra battery mod on the mav pro. i think i will try to open mine and add hook ups for adding batteries to it. why better then opening the quad.