Charging battery with constant voltage / DS24 adapter cable

[xilef]

There are adapter cables for charging the Mavic batteries with non-DJI chargers like this:

DS24 Ladeadapter für DJI MAVIC Akku Ladekabel mit Kontaktschutzstecker LiPo Balancer Kabel ZUBEHÖR

- What is the allowed voltage range accepted by the Mavic intelligent battery? (I think nominal is 13.05V?)
- Can I charge with a constant voltage source? Or in other words: Is the current regulation/limitation integrated in the battery circuit?

 

[xilef]

Does nobody know how the intelligent battery is working in detail?
There is a lot of contradictory information out there.
Some people write, that the charger has to limit the current, some write that the battery does it....

 

[xilef]

Seems that no one is interested in this topic :-(
Nevertheless, here some infos which I found out in the meantime:

The mavic pro intelligent battery has no current limitation inside! So the charger has to be a CV/CC supply (13.05V/4.5A).
Using a simple constant voltage source is not possible (and will damage the battery).

Charging works with my Junsi iCharger 4010DUO by using the Pb mode.
Settings:
- Current: 4.5A
- End voltage: 2.18V/cell (=13.08V)
- Charge end current: 1%
Battery has to be switched on before connecting it to the charger.

 

[Lake_Flyer]

Seems that no one is interested in this topic :-(
Nevertheless, here some infos which I found out in the meantime:

The mavic pro intelligent battery has no current limitation inside! So the charger has to be a CV/CC supply (13.05V/4.5A).
Using a simple constant voltage source is not possible (and will damage the battery).

Charging works with my Junsi iCharger 4010DUO by using the Pb mode.
Settings:
- Current: 4.5A
- End voltage: 2.18V/cell (=13.08V)
- Charge end current: 1%
Battery has to be switched on before connecting it to the charger.

Why a non DJI charger? What's the benefit exactly?

 

[xilef]

There are lot of reasons....
- As far as I know, there is no DJI charger which can be supplied with car battery and can charge multiple batteries at once.
- I don't buy the Ebay-China-rubbish.
- I already have a lot of equipment from my airplane models (e.g. the Junsi Charger...) which I try to reuse instead of buying a lot of new stuff.
- I'm interested in electronics => I always want to know what happens inside

 

[Lake_Flyer]

OK, I see your point. I have a ton of stuff lying around after almost 40 years of RC flying, including several chargers.

 

[robygre]

Hello,

Home and car charger have different specs concerning output DC voltage
home : 13,05 V
car : 13,2 V
Internal battery circuitry might do the job, but is surprising to see 2 types of voltages.

Why did you chose 4,5 A (official charger dc output is 3,83A) and what does mean 1% end charge current ?

Regards,

Seems that no one is interested in this topic :-(
Nevertheless, here some infos which I found out in the meantime:

The mavic pro intelligent battery has no current limitation inside! So the charger has to be a CV/CC supply (13.05V/4.5A).
Using a simple constant voltage source is not possible (and will damage the battery).

Charging works with my Junsi iCharger 4010DUO by using the Pb mode.
Settings:
- Current: 4.5A
- End voltage: 2.18V/cell (=13.08V)
- Charge end current: 1%
Battery has to be switched on before connecting it to the charger.

 

[xilef]

I do not understand the internal battery circuitry completely yet.
It's not clear to me, what it does at the end of the charge process. Does it limit the current then after all? Or does it only stop charging when the end voltage is reached and the current is defined by the charger...?
I'll do some further tests and come back here...

I choose 4.5A to fasten up the charge process. Should be safe because the widely used 3rd party charger (http://www.amazon.de/gp/product/B06ZYWHYWF) also has 4.5A.

For Junsi charger "end charge current" in Pb mode means, that it ends the charge process as soon as the current drops below this value.
Because the intelligent battery stops the charge process itself, I selected the lowest possible value (=1% @ 4.5A = 45mA)

Regards

 

[xilef]

Did some further tests and unfortunately it seems that the "intelligent" battery is not as intelligent as expected...

The current is not regulated by the battery at any time.
This means, the charge current only depends on the charger.
The battery circuitry only switches off when the end voltage is reached (4.35V/cell).

That is not a correct charging method for LiPo batteries.
Normally they are charged with the following sequence:
1) Constant current until voltage reaches end voltage
2) Constant voltage until current falls below a certain percentage.

With the Mavic method, it's possible that the battery is not fully charged because depending on the charger the current is still very high when reaching the end voltage (and therefore the charge process is stopped).

 

[robygre]

I have tried Pb and LiHV programs to charge Mavic Air batteries with success.
Skyrc dedicated E660 uses LiHV program for mavic pro batteries (air and pro both have Lihv batteries).
Pb program can be used if the charger enable to set the voltage for each element. It is not available on my skyrc chargers (D100 and S60). I use Lihv program in this case. Is is available on my ISDT Q6 plus charger.