Mavic Mini Charging Voltage for Fly more Charger

[BenF]

First thing I did was to put it on the DJI charger with a Voltage/Amp reader.
I was expecting 5Volts charging voltage, but its 12.1 Volts at 1.47 Amps!
So... I wonder what the DJI charger does with normal USB devices?

 

[BlueGhost]

I think that is pretty standard for quick charging, phone and power bricks do the same. High volts low amps, but if the device isn't capable of quick charging, it should put out the normal 5 volts.

 

[DanMan32]

The overall concern is watts, which is volts x amps. The higher the volts, the less amps for a given wattage.

Now why do we care if we up the voltage rather than amps? Two reasons:
Too much amps through a wire will burn it out.
Wires have a small but finite resistance. As you push more amps through a resistance the more voltage and ultimately wattage is lost through the resistance.

This is why your stove, oven, AC, electric clothes drier and water heater typically runs on 240v.

So to get more watts to charge the battery with small USB wires, QC and iSmart use higher voltages.

QC uses 5v, 9v, and 12v.

Basing the results you show in your picture, you're delivering 17.8W.
At 5v, you'd be drawing 3.55A for the same amount of watts.

 

[old man mavic]

also it looks like the cables supplied from the wall unit to the hub are thicker to be able to carry the higher load

 

[DanMan32]

Maybe, but most cables except very cheap ones can handle 2A, definitely 1A.

 

[Mori55]

So if I want to buy a wall charger to charge the hub and controller at the same time that’s comparable to the dji charger what one should I get ?

 

[BenF]

So if I want to buy a wall charger to charge the hub and controller at the same time that’s comparable to the dji charger what one should I get ?

I don't think the remote controller is a quick charge. Maybe it is. Would be easy enough to find out.
I charge the remote controller with a normal USB 5V charger. The MM can also be charged with a normal 5Volt charger also, but it will just take longer.
My Volt/Amp device has two USB ports on it. Not sure if plugging the controller into the second USB port while at 12 volts will hurt the controller. If the controller can handle 12 volts, then it would probably be ok. If not, then the controller will get fried.
The DJI charger stays at 5 volts when I charge other things, like a GoPro battery, etc.

 

[DanMan32]

I would hope that monitor would not have both USB ports tied directly to each other. Each QC device/charger pair should negotiate voltage independently.

 

[est73]

I don't think the remote controller is a quick charge. Maybe it is. Would be easy enough to find out.

It does... the rate the lights blink changes just like the battery hub when you use the quick charger vs a standard charger.

 

[Metaeditor]

It sounds like QC3 standard .So its should be possible to charge directly with 12V also the battery inside the mavic mini ? Some one tested this ?

 

[TDZHDTV]

Its your only option if you don’t have the combo version

 

[TDZHDTV]

The overall concern is watts, which is volts x amps. The higher the volts, the less amps for a given wattage.

Now why do we care if we up the voltage rather than amps? Two reasons:
Too much amps through a wire will burn it out.
Wires have a small but finite resistance. As you push more amps through a resistance the more voltage and ultimately wattage is lost through the resistance.

This is why your stove, oven, AC, electric clothes drier and water heater typically runs on 240v.

So to get more watts to charge the battery with small USB wires, QC and iSmart use higher voltages.

QC uses 5v, 9v, and 12v.

Basing the results you show in your picture, you're delivering 17.8W.
At 5v, you'd be drawing 3.55A for the same amount of watts.

Dan, you seem to know your stuff when it comes to battErie’s, question for you, if you use a standard 5v charger would this improve battery life over quick charging? I’m wondering is it almost like a trickle charge? Cheers

 

[DanMan32]

Dan, you seem to know your stuff when it comes to battErie’s, question for you, if you use a standard 5v charger would this improve battery life over quick charging? I’m wondering is it almost like a trickle charge? Cheers

Excellent question. For our quads, I don't think it matters since the batteries don't get warm at all charging. There's much more stress on them flying.
For smart phones, those get quite warm on rapid charge.

But most of the increased watts charging is before 80%.

 

[DanMan32]

It does... the rate the lights blink changes just like the battery hub when you use the quick charger vs a standard charger.

I tried with QC output of my power bank vs "iSmart" output that doesn't rapid charge according to my phone and tablet. Using both on the RC, LED blink was the same.
The only way to know for sure is to put a meter on it. If Santa doesn't bring one, I'm buying one.

 

[DanMan32]

It sounds like QC3 standard .So its should be possible to charge directly with 12V also the battery inside the mavic mini ? Some one tested this ?

The charger and charged device need to negotiate the voltage, with the charged device making the request. You would not want to push 12v before the device requests and is ready for it.

 

[ashsys]

will charging on 10W adapter is good for my MM battery health? I mean charging slowly is good for battery on long run than fast charging with 18W adapter ?

 

[BenF]

Here is a good article about the 18650 battery, which the mini uses: I.E. more cycles, can be obtained by lowering the charge currents.

How to Prolong the Life of an 18650 Battery

How to Prolong the Life of an 18650 Battery: There are many important specifications for an 18650 battery, including: Capacity (mAh) Discharge Current (A) Charge Current (A) Maximum Cycle Life In this Instructable, I want to talk about maximum cycle life, and how you can use this measure to …

www.instructables.com

 

[Deleted member 103366]

Uum when talking about the charge 'passed' to a battery, are we not concerned with the Coulombs of electricity passed?

Yes the higher the voltage the lower the current for a given wattage, not questioning that. But Coulombs (C) passed = current (in Amps) x time ( in seconds).
So 1A for 1hr = 3600C, irrespective of the voltage and the power of the supply.
I realise the situation is not as simple as that as these chargers and probably any controllers in the device under charge, 'fiddle' with things.
I also realise that a higher voltage charger may be able to drive more current through a battery but ultimately, to reach full charge, are not the required number of Coulombs the same?