Mavic2 Battery Controller Mods

[mitmit]

which chip is used in the battery controller Mavic 2?

 

[SergeyCrypto]

View attachment 55492

Thanks!

 

[mitmit]

Thanks!

If you find any info for this IC please share

 

[mitmit]

If anyone has M2 battery controller board for sale I will take it.

 

[beanbubba]

FYI to the group. After smoking 3 battery controllers, it has become very evident that the voltage range on the controller is very narrow. I was testing 5S with Lolo and smoked 2 controllers in a row. I then smoked a 3rd while the bird was on the bench (back to 4S) and had a micro short/spark on the other end of the bird. This smoked the battery controller too (bird and other accessories were just fine).

 

[chazz]

FYI to the group. After smoking 3 battery controllers, it has become very evident that the voltage range on the controller is very narrow. I was testing 5S with Lolo and smoked 2 controllers in a row. I then smoked a 3rd while the bird was on the bench (back to 4S) and had a micro short/spark on the other end of the bird. This smoked the battery controller too (bird and other accessories were just fine).

Ouch! sounds expensive! One of the reasons i quit the hobby! i had to save money for my gambling addiction.

My P3 didn’t have the issue with blowing boards but it did have the issue of erroring and not letting you power up with more than 17.8V. For me to get a 5s to work on my phantom I stepped down the voltage by using diodes in series to make my 5s - 21V lion = 17.8V. (this works with highly overcharged 4s too) The plan was to fly it down to maybe 3.5V per cell and use a programmable timer relay with a parallel wire to bypass the diodes to get the voltage (3.5*5=17.5) stepped back up while in flight. But with the P3 I ended up realizing as long as you got past the power up at 17.8V it was ok to step the voltage back up to 21V without erroring or burning anything so I didn’t need the timer relay and I could just bypass the diodes right after it was powered up before taking off. I don’t know if this makes sense and it’s probably the most readneck way of doing it and there’s probably much better ways.
Dude it was hilarious, you should have seen my woman’s face when she came down to the cave seeing me with this homemade lion 5s battery with this timer stuck to it. I still don’t know if she believes it was just a battery.

Disclaimer: I’m no engineer and don’t know if there was any benefit if using the relay or if the diodes could handle the current over time.

 

[beanbubba]

Does anyone know the name/specification for the mini-balance cable connector on the battery controller? Need to order a custom cable.

 

[beanbubba]

Ouch! sounds expensive! One of the reasons i quit the hobby! i had to save money for my gambling addiction.

My P3 didn’t have the issue with blowing boards but it did have the issue of erroring and not letting you power up with more than 17.8V. For me to get a 5s to work on my phantom I stepped down the voltage by using diodes in series to make my 5s - 21V lion = 17.8V. (this works with highly overcharged 4s too) The plan was to fly it down to maybe 3.5V per cell and use a programmable timer relay with a parallel wire to bypass the diodes to get the voltage (3.5*5=17.5) stepped back up while in flight. But with the P3 I ended up realizing as long as you got past the power up at 17.8V it was ok to step the voltage back up to 21V without erroring or burning anything so I didn’t need the timer relay and I could just bypass the diodes right after it was powered up before taking off. I don’t know if this makes sense and it’s probably the most readneck way of doing it and there’s probably much better ways.
Dude it was hilarious, you should have seen my woman’s face when she came down to the cave seeing me with this homemade lion 5s battery with this timer stuck to it. I still don’t know if she believes it was just a battery.

Disclaimer: I’m no engineer and don’t know if there was any benefit if using the relay or if the diodes could handle the current over time.

You may be the most redneck engineer I have ever met

 

[beanbubba]

Does anyone know the name/specification for the mini-balance cable connector on the battery controller? Need to order a custom cable.

Best guess is the cable is this kind:

https://www.amazon.com/1-25mm-PicoBlade-Female-Connector-Housing/dp/B07GNNFVVR/

 

[beanbubba]

Verified the connector is called:

5 Pin Molex Picoblade 1.25mm

Note: it is NOT one of the JST standards.

JST connector - Wikipedia

 

[chazz]

Verified the connector is called:

5 Pin Molex Picoblade 1.25mm

Note: it is NOT one of the JST standards.

JST connector - Wikipedia

Good you found it i hope it fits when you get it in. I would have gone right to the jst. I have a hard time measuring the difference between 1.25 and 1mm. I cant see that small a take pictures with it next to a rule that i can zoom in on and then i buy both anyway.

 

[DanMan32]

Ouch! sounds expensive! One of the reasons i quit the hobby! i had to save money for my gambling addiction.

My P3 didn’t have the issue with blowing boards but it did have the issue of erroring and not letting you power up with more than 17.8V. For me to get a 5s to work on my phantom I stepped down the voltage by using diodes in series to make my 5s - 21V lion = 17.8V. (this works with highly overcharged 4s too) The plan was to fly it down to maybe 3.5V per cell and use a programmable timer relay with a parallel wire to bypass the diodes to get the voltage (3.5*5=17.5) stepped back up while in flight. But with the P3 I ended up realizing as long as you got past the power up at 17.8V it was ok to step the voltage back up to 21V without erroring or burning anything so I didn’t need the timer relay and I could just bypass the diodes right after it was powered up before taking off. I don’t know if this makes sense and it’s probably the most readneck way of doing it and there’s probably much better ways.
Dude it was hilarious, you should have seen my woman’s face when she came down to the cave seeing me with this homemade lion 5s battery with this timer stuck to it. I still don’t know if she believes it was just a battery.

Disclaimer: I’m no engineer and don’t know if there was any benefit if using the relay or if the diodes could handle the current over time.

If you want to have a fixed step down of voltage, you can use a zener diode. They have them in wattages/currents to qualify for power circuits. Then you'd only need one, rather than 5 regular silicon diodes.
I'd also suggest 2 LEDs, but their typical current rating is only 20mA.
Note that you also need to consider power dissipation. 4v drop at say 1A is 4W that is dissipated.

 

[beanbubba]

Good you found it i hope it fits when you get it in. I would have gone right to the jst. I have a hard time measuring the difference between 1.25 and 1mm. I cant see that small a take pictures with it next to a rule that i can zoom in on and then i buy both anyway.

These were the only ones I could find ready to ship in the US. They are priced right!

US SHIP 10 SETS 5Pin 15cm Micro JST Molex Picoblade 1.25mm Male Female PCB Board | eBay

 

[chazz]

These were the only ones I could find ready to ship in the US. They are priced right!

US SHIP 10 SETS 5Pin 15cm Micro JST Molex Picoblade 1.25mm Male Female PCB Board | eBay

I usually look to amazon for the quick shipping. I think these are the same.

https://www.amazon.com/gp/product/B075ZP5HDL/ref=ox_sc_act_title_1?smid=A2IDIBA7YZAARZ&psc=1

 

[beanbubba]

I usually look to amazon for the quick shipping. I think these are the same.

https://www.amazon.com/gp/product/B075ZP5HDL/ref=ox_sc_act_title_1?smid=A2IDIBA7YZAARZ&psc=1

Good find. My search was too specific. Thx.

Now find one with a 4S balance connector on one end

 

[beanbubba]

It fits! Thanks for the link chazz.

NOTE: the specification is positively:

Male 5 Pin Molex Picoblade 1.25mm 28AWG

Molex Connector Part Number - 15134-0500

 

[beanbubba]

Here's an idea to try and make things a little cleaner/tighter on the mod. A couple small drill holes and some good black paint (along with the custom balance cable extender), and you have a pretty tight looking mod. I then route the balance cable out the back side to connect to the external battery. Now you don't have to mess/haggle with the semi-permanent mounted battery controller on each flight.

This also makes the bird a "pickup truck" with a nice payload bay for future projects

 

[beanbubba]

Here is it paired with the front volt meter display. I am reworking the payload jettison system on the bottom side that is really tight. Hope to have done in a few days:

 

[lolo780]

The voltmeter could double as a nose cone if rounded off with some carved foam.

Filling in the empty battery compartment would be a big plus. I was going to use a tiny drill bit to put vent holes above the esc board which are small enough so nothing can drop inside.

 

[beanbubba]

The voltmeter could double as a nose cone if rounded off with some carved foam.

Filling in the empty battery compartment would be a big plus. I was going to use a tiny drill bit to put vent holes above the esc board which are small enough so nothing can drop inside.

I guess I could take a salvaged battery case and skinny it down for the aerodynamic effects.

I just can't imagine at our relatively low speeds that aerodynamic drag could add up that much, but you never know unless you have a wind tunnel.