Mavic Pro Battery - Over Voltage Repair (third LED flashing)

Modifications
1

I haven’t flown my Mavic in months, 12+ months.

I took it out of mothballed to get it ready for a member on here CoC. Three batteries charged as normal but the fourth charged and then stopped with the third LED flashing, code for short circuit.

I tried it in the Mavic but got a battery error so I left it resting overnight. In the morning I was surprised when it showed full LED’s and no error message in the App.

The App flagged a message saying “ Drain Battery to 5% and update”.

The battery has a .05 imbalance with one cell reaching 4.22V while the rest only reach 4.17 which stops the charging.

Has anyone had this happen?

2

I’m guessing all four batteries had entered full on hibernation mode, prior to the charge up?

The fourth one wasn’t in some kind of limbo was it?

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3

I had a battery do this on me in Nov '17 … when mine was a year old, frequently used, and it happened immediately after a firmware update.

Never found the cause and, because of other things, I ended up with a new battery courtesy of HobbyMounts. (Long story!).

4

Although I didn’t fly it, I periodically checked on the batteries by pressing the button so I doubt they entered hibernation.

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5

I’ll be disassembling the battery to balance the cells if updating fails, so watch this space…:rofl:

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6

I tried to open the battery as carefully as possible, it’s not easy as you have no choice but to break tags and glue.

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I’ll need to make a step down connector to balance charger next.

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7

Well it looks like this battery is now dead…,

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8

:pensive:

Tried one of these?

https://www.amazon.co.uk/Philips-Heartstart-Semi-Automatic-Defibrillator-Carry/dp/B013U94TC2/ref=sr_1_1_sspa?dchild=1&keywords=defibrillator&qid=1600340659&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExNVNaS1A3TEZPWFFBJmVuY3J5cHRlZElkPUEwNDU2MDUySDZYT0pRMDdSRU1KJmVuY3J5cHRlZEFkSWQ9QTA4NDQxODFFUU9ONFZXVVNGQzgmd2lkZ2V0TmFtZT1zcF9hdGYmYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

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9

:rofl:

10

I fancy Lance could fashion something similar on the kitchen table for less :wink:

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11

Easy I’ve got 240AC by the kitchen table, good for sending one to a parallel universe…:rofl::rofl:

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12

Well,may as well have some fun,as its dead,take it outside and hit a nail in it! great fun watching these things burn and explode,its how i dispose of any of my own batteries,when they bloat to much. :+1:t2: :+1:t2: :+1:t2: :rofl: :rofl: :rofl:

13

:thinking:

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14

Most significant is the lack of new MP batteries anywhere.

Heliguy had some a while back … I procrastinated and they’d gone.

Not seen any anywhere for a while … genuine or genuinely iffy.

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15

EBAY ? :grimacing: :grimacing:

16

Yeah - some - but ones I’m willing to part money for … :fearful:

Even some very non-genuine ones on Amazon. I’d try them before ebay.

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17

If I was going to go down the iffy route … may as well save £££ and go for Gearbest @ £36.

18

I had a quick look and they are becoming like hens teeth…

19

I think I might contact HobbyMounts and Heliguy and ask them to let me know when they get a genuine one in stock.

All three of mine seem to be OK when I recharge them … but sods law dictates they’ll all start failing in rapid succession when the last ever genuine one has gone.

20

Maybe an opportunity to experiment with a Turnigy Lipo, I’ll try it as the circuitry is working…:thinking:

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Off to browse HB for the closest size…:grin:

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