I just read in official FAQ here http://www.dji.com/support/product/mavic#faq-1_0_2 (tab "others") that DJI don't recommend charging Mavic RC from powerbank.

Does it mean any powerbank including DJI "Battery to Power Bank Adaptor" from Mavic Combo??
If not, then does it mean that we can use any good powerbank with 2A output (DJI adaptor provide 2A)?

FAQ:
3. Can I charge the Mavic's remote controller using a mobile power bank?
It is not recommended to charge the remote controller with a mobile power bank. This may damage the coulometer. Battery level readings for the remote controller may become incorrect, and the battery consumption speed may become greater than the charging speed.

Probably you need constant full power to charge the RC and when you use a battery it might not give  full power once the battery srat draining.

dronist Posted at 2017-3-3 18:20
Probably you need constant full power to charge the RC and when you use a battery it might not give  full power once the battery srat draining.

DJI power bank should give constant power (I hope, but I still don't test it). Anyway  this is assumptions, and why we can't hear exact answer in official product support forum?

This is an important issue, because you can take to the trip as many Mavic batteries as you want. But after the third or fourth flight your RC battery will be empty, and only chance to continue flight will powerbank using.

And, for people whose phone energetically charging from RC, additional power may require after first flight, and in these conditions better strategy is using power bank all the time during flights.

rusm2 Posted at 2017-3-4 01:16
DJI power bank should give constant power (I hope, but I still don't test it). Anyway  this is assumptions, and why we can't hear exact answer in official product support forum?

This is an important issue, because you can take to the trip as many Mavic batteries as you want. But after the third or fourth flight your RC battery will be empty, and only chance to continue flight will powerbank using.

You most likely can use dji battery to power, but your right info is a bit vague, regarding other power banks as in number 3 answer is very clear.

Regarding your phone if there is a big draw on your phone that sounds like a problem, I only have very slight trickle on mine after using three Mavic batteries.

rusm2 Posted at 2017-3-4 01:16
DJI power bank should give constant power (I hope, but I still don't test it). Anyway  this is assumptions, and why we can't hear exact answer in official product support forum?

This is an important issue, because you can take to the trip as many Mavic batteries as you want. But after the third or fourth flight your RC battery will be empty, and only chance to continue flight will powerbank using.

As Hallmark said, if the phone is charging then there is a problem and if DJI saying don't use mobile power bank I would NOT use it.

It all come back to warranty if something happen they will tell you you did not follow directions.
You have a point  about when you are on the fields you need to keep going so fa where I go I have my and  I charge mine using the car outlet.

Maybe one the DJI MOD can shed a light here!

There are many places on planet without cars, roads and outlets, and it's amazing.

Still awaiting comments from DJI stuff here.

rusm2 Posted at 2017-3-4 12:17
There are many places on planet without cars, roads and outlets, and it's amazing.

Still awaiting comments from DJI stuff here.

Why not send PM to a dji mod.

rusm2 Posted at 2017-3-4 12:17
There are many places on planet without cars, roads and outlets, and it's amazing.

Still awaiting comments from DJI stuff here.

It really depends, the main concern is that the powerbank doesn't offer enough power to charge the RC consistently, so there is a chance it damage the RC if the power bank is not good. So it's not recommended to use any power banks, including DJI's converter. So you do it at your own risk.

BTW, how do you think repair center is going to know if the RC is damaged by powerbank or regular charging?

DJI-Thor Posted at 2017-3-4 22:38
It really depends, the main concern is that the powerbank doesn't offer enough power to charge the RC consistently, so there is a chance it damage the RC if the power bank is not good. So it's not recommended to use any power banks, including DJI's converter. So you do it at your own risk.

BTW, how do you think repair center is going to know if the RC is damaged by powerbank or regular charging?

Thank you, DJI-Thor. I understand your point of view, but one case does not give me to calm down:
Just now I connected my RC to laptop via USB cable, and RC charging from laptop. It charging independently of on or off RC state, and running or not DJI Assistant. It showing "charging" on display and took 500-600mA from usb port.

So, my (and any other random) laptop surely can not be considered as good and consistent power source, it can deliver maximum 0.5-0.7A with unstable voltage and current. And connecting RC with laptop via cable is a necessary regular procedure (for firmware upgrade and logs download) that described in manual, so it can't be dangerous.

As I experienced, sometimes vendors are overcautious and including in tech manuals strange info, for example to avoid responsibility of using cheap 2 dollars power banks  in our case.

As described above, possibility of charging RC from autonomous power source is important and necessary in some drone using cases. So, could you please rise this case to engineering team for clear answer about risks of using DJI power bank or another good true 2A output power bank? Is it just overcautious, or Mavic RC really more exposed at bad power source risk, than any other thousands LiIon and LiPo devices?