Battery mod thread

[Marcuchinonis]

Hel stock bms doen't works after change cells. I can switch on the dron only if I attach an external battery to ++ - pins from battery drone connector. When a unplug the external battery, the dron, switchs off. It seems like the bms in not more activated before extract original samsung cells. I've tried to reflash the dron with the bams inside the drone. Flashing works great, but bms doesn't activates. I'm unhappy, because I own Mavic Pro cells (3850 mAh) and I'd like to test, but i don't have a free bms to test. 2 MP cells are 130 gr --- 3850mAh. 2 MM cells, 100 gr --- 2400 mAh. Maybe you can fly about 35 min?

 

[aforww]

This thread has turned into how to burn your house down.

 

[Marcuchinonis]

I will do a time test tomorrow, let's see if anyone can spot the difference.......

An hour finally?

 

[Justinswidebody]

An hour finally?

We will see. With this combo the mini has no problem flying with 465grams all up weight

 

[Marvmpilot]

We will see. With this combo the mini has no problem flying with 465grams all up weight

Have really enjoyed your thread! Did you ever end up testing with the Mavic Air props?

 

[Justinswidebody]

Have really enjoyed your thread! Did you ever end up testing with the Mavic Air props?

Working on that too. That's going to take more work. I have adapters designed to work, but can't get them perfectly balanced 3d printing, so would have to out source to someone with a CNC machine and a lathe ... That would cost me about $100 for 4 adapters. So I'm working on a different plan of action. We shall see.

 

[Marcuchinonis]

Hello. Anybody has done a parallel method to swap cells. What's the right way to ensure goal? Maybe connecting new cells in this order: +, +-, - ?

 

[Justinswidebody]

Hello. Anybody has done a parallel method to swap cells. What's the right way to ensure goal? Maybe connecting new cells in this order: +, +-, - ?

I have tried this method with batteries that have been updated and I was unsuccessful.
The only true way is with batteries that haven't been updated from what I have seen.

The battery you tried, what happens when you plug it into the charger?

 

[Marcuchinonis]

I have tried this method with batteries that have been updated and I was unsuccessful.
The only true way is with batteries that haven't been updated from what I have seen.

The battery you tried, what happens when you plug it into the charger?

When I connect the charger, the four white LEDs light up at the same time and flash. The battery is charged 100%.

 

[Justinswidebody]

When I connect the charger, the four white LEDs light up at the same time and flash. The battery is charged 100%.

So when you put it in the mini, it will turn on but you get battery cell error?

 

[Justinswidebody]

If you don't mind taking it back apart, can you make sure your thermister didn't come loose from one of the solder points? This happened to me before and it did the same thing. Just resolder the thermister back to its solder joint

Thermister in the little sensor that is glued onto the factory battery

 

[Marcuchinonis]

So when you put it in the mini, it will turn on but you get battery cell error?

The drone don't turns on. if I plug an extra external battery, the drone turns on, but when I try to take off, a flag message tells: "cell error". I have checked voltage at bms connections pins: it's 0. The board seems not to be activated.

 

[Marcuchinonis]

If you don't mind taking it back apart, can you make sure your thermister didn't come loose from one of the solder points? This happened to me before and it did the same thing. Just resolder the thermister back to its solder joint

Thermister in the little sensor that is glued onto the factory battery

The thermister seems to be ok. I've checked yet. That.s a issue I had with mavic Air batterys. The difference betwen MM and MA batterys is than MA one, when activated into the drone via external battery (with UAV clip p.e.), the bms remains activated por ever. The MM one remains off.

 

[Justinswidebody]

The drone don't turns on. if I plug an extra external battery, the drone turns on, but when I try to take off, a flag message tells: "cell error". I have checked voltage at bms connections pins: it's 0. The board seems not to be activated.

Unfortunately it's bricked then. As soon as you have cell error it's a goner

 

[Tesla Hertz]

i am at that stage , i have not updated the battery firmware, do you have to do a hot battery swap so the bms is not bricked ?

 

[Marcuchinonis]

i am at that stage , i have not updated the battery firmware, do you have to do a hot battery swap so the bms is not bricked ?

I swaped a non updated battery with sony cells, but only semi-hot swap (only + and - , not +-, maybe this is the problem) and the bms is briked. I think is not clear what's the way.

 

[Justinswidebody]

i am at that stage , i have not updated the battery firmware, do you have to do a hot battery swap so the bms is not bricked ?

As long as you have not done a firmware update on battery and still get a prompt saying you need to, then no you do not need to do a hot swap.

 

[Justinswidebody]

I literally have a bms that I just plug batteries into whenever I want. No cells attached at all.

 

[Marcuchinonis]

I literally have a bms that I just plug batteries into whenever I want. No cells attached at all.

Awsome!!! mine still got a prompt when a swap. That's the mistery... maybe, simply you are a lucky man

 

[Justinswidebody]

Awsome!!! mine still got a prompt when a swap. That's the mistery... maybe, simply you are a lucky man

I have 3 of these adapters made