Field charging with IMAX B6

[Daz393]

Evening all.
I have been an RC plank and heli pilot for several years, and charge at the field with my imax B6 chargers.
My Mrs just bought me an unused P3a from her colleague, and it has the indoor charger, and 2 flight batteries.
My flying field is a 20 mile round trip.
My question is, is it possible to use the IMAX or is there some special circuitry inside the battery which won’t allow this?
Cheers
Daz

 

[LarBear360]

Evening all.
I have been an RC plank and heli pilot for several years, and charge at the field with my imax B6 chargers.
My Mrs just bought me an unused P3a from her colleague, and it has the indoor charger, and 2 flight batteries.
My flying field is a 20 mile round trip.
My question is, is it possible to use the IMAX or is there some special circuitry inside the battery which won’t allow this?
Cheers
Daz

These batteries are very special nor do I believe the connections on the IMAX are compatible. I only use DJI OEM batteries and chargers.

If you need to charge in the field DJI sells a car charger kit for $85.

 

[WV. Rootman]

DJI has it own circuitry that balances out the charge to their intelligent battery. It has to be their charger. Find a nice open field nearby and test it. It is not like flying a rd plank. In some ways, it’s not really flying. Please read the manual on line. This is a good start.
DJI Phantom 3 Advanced Accessories & Tips - Phantom Help

 

[WV. Rootman]

Also register your P3a with the FAA. It cost $5. FAADroneZone

 

[Daz393]

Thanks guys

 

[kerrylaw7307]

I may be missing something here, and correct me if I am wrong guys, but the DJI "charger" is nothing more than a power supply. ALL charging of the cells and balancing of the battery is done by the batteries BMS, ( Battery Management System ) circuitry which is built into the battery, not the charger.

The DJI "charger" has no intelligence or way of balancing the flight batteries as it merely supplies a regulated 17.5 volts at up to 5.7amp, if needed by the battery BMS board.

That being said, I use a car charger, that plugs into the cigarette lighter receptacle, and provides 17.5vdc to the battery. Made to charge DJI P3P batteries from your car/truck. Look for something like... "17.5V 4A 70W Vehicle Car Power Outdoor Charging Charger For DJI Phantom3 Battery". Ebay carries them for less than $10. Remember, the BATTERY has the intelligence, NOT the power supply ( charger ). Supply it with a regulated power supply of 17.5 volts and able to provide 6 amps and you will be fine.

 

[LarBear360]

I may be missing something here, and correct me if I am wrong guys, but the DJI "charger" is nothing more than a power supply. ALL charging of the cells and balancing of the battery is done by the batteries BMS, ( Battery Management System ) circuitry which is built into the battery, not the charger.

The DJI "charger" has no intelligence or way of balancing the flight batteries as it merely supplies a regulated 17.5 volts at up to 5.7amp, if needed by the battery BMS board.

That being said, I use a car charger, that plugs into the cigarette lighter receptacle, and provides 17.5vdc to the battery. Made to charge DJI P3P batteries from your car/truck. Look for something like... "17.5V 4A 70W Vehicle Car Power Outdoor Charging Charger For DJI Phantom3 Battery". Ebay carries them for less than $10. Remember, the BATTERY has the intelligence, NOT the power supply ( charger ). Supply it with a regulated power supply of 17.5 volts and able to provide 6 amps and you will be fine.



View attachment 103717View attachment 103718

I agree $85 for a car charger is too much. That's why I don't own one.

There are a multitude of non-DJI accessories available. Use at your own risk. Any problems with the battery and you are stuck. DJI warranty will not cover any damage to the drone or battery when using non-DJI accesories.

 

[3rdof5]

I simply use a portable power box (a unit with a glassmat battery and a 150w invertor) that recharges itself while driving via my 12volt outlet. It can use the factory 120v ac dji charger and i get about 4 full flight battery charges before it needs recharging.

 

[solentlife]

Blimey - I have never read so much rubbish about charging a DJI battery !!

Imax B6 charger will only charge to 4.2V per cell which is not enough. The DJI packs are HIGH Voltage LiPo and need the LiHV setting of the B6 mini or Accucel 6 etc. to charge to 4.35V per cell.

The DJI battery does not allow any balance lead connection - so you have to charge via the main lead without balance port connection. eBay has many adaptor leads for LiPo charger to DJI batterys. About $2 a lead ...

How ?

1. Set the LiPo charger to charge only mode and LiHV.
2. Set at 4S and 5A
3. Switch ON battery BEFORE connecting to charger so that DJi Battery board does not default OFF.
4. Connect to charger and press start.

Away you go ... simple.

OK - why does the board refuse to allow a LiPo charger to charge if you do not switch on first ? Because the DJI charger is a constant voltage regulated 17.5V power brick. It has no programming at all. When you connect the DJI charger - it thumps 17.5V at the battery regardless and the board accepts this and then regulates the charging.
When you connect a LiPo charger - this does not thump 17.5V at the pack ... it starts low and rises which means Board does not allow passage of charge. But switching on the pack first over-rides the board and charge proceeds nicely.

I like using a LiPo charger - Why ? The LiPo charger provides a 'double safety' factor. The DJI charger is what is termed 'dumb brick' - in that it will just keep thumping out 17.5V whatever happens. It relies on the battery board to provide any safety measure. So ally a LiPo charger and the charger will automatically shut off charge if any fault detected ... giving a double safety factor.
Second - you have a readout telling you how many amps going in ... voltage at that time ... and the total mA's put in.

Here's my Accucel 6 80W charging a DJI P3 battery :



Last point .... some claim that using any charger other than a DJI will void warranty ... Total rubbish as the battery has no way to record what charger was used and in fact a LiPo charger such as you see in the picture is much safer than any DJI charger ..... QED.

Nigel

 

[solentlife]

I agree $85 for a car charger is too much. That's why I don't own one.

There are a multitude of non-DJI accessories available. Use at your own risk. Any problems with the battery and you are stuck. DJI warranty will not cover any damage to the drone or battery when using non-DJI accesories.

Cigarette lighter chargers for DJI batterys are about $5 on eBay ... and I have one - works as good as the over-priced DJI item ....

Nigel

 

[kerrylaw7307]

SOLENTLIFE... I agree 100% good post. And "WV Rootman's" statement .... DJI has it own circuitry that balances out the charge to their intelligent battery. It has to be their charger. <<< that is simply not true. The DJI "charger" has no intelligence or way of balancing the flight batteries as it merely supplies a regulated 17.5 volts at up to 5.7amps if needed.

 

[solentlife]

SOLENTLIFE... I agree 100% good post. And "WV Rootman's" statement .... DJI has it own circuitry that balances out the charge to their intelligent battery. It has to be their charger. <<< that is simply not true. The DJI "charger" has no intelligence or way of balancing the flight batteries as it merely supplies a regulated 17.5 volts at up to 5.7amps if needed.

Thanks...

I have 4 ways to charge DJi P3 batterys :

1. Original power brick DJI give you.
2. Car Ciggy lighter adaptor that does same as DJI charger
3. 3+1 Charger that simultaneously charges 3 batterys AND the Controller unlike the crap multi stations I see that are NOT simultaneous, but are sequential. And is cheaper than those crap !!
4. My LiPo programmable chargers - all 5 of them.

2 and 4 are fully field capable .... 1 and 3 need Inverter to work from 12V source. I know which I prefer !!

Nigel

 

[frankgf321]

I'm also knew to flying (less than a year) and have posted questions before. Solentlife (Nigel's) post really intrigued me. I'm only using the DJI brick charger and had been assuming that it was "smart" and safe. But after reading Nigel's post was wanting to get a charger like his. I went to Amazon & found both the 50W and 80W versions. I'm assuming the difference is rate of charge and I alway's prefer a slower rate as I feel it's less stress on the battery. Is this the case or is there another difference between these two chargers. Also, there was a note about one coming with a power supply and the other didn't. Is there something else I need to purchase with this charger?? Thanks in advance guys. I spend a lot more time reading this forum than flying!

 

[solentlife]

OK Frank ...

First the Accucel comes in various forms - with the 50W and 80W being the common ones. The Accucel is best bought from Hobby King at $34 instead of Amazon $47 ..... The only factor then is location and which warehouse of HK you buy from. They also need a power supply.

I do not advise buying a charger that has power supply built in, its usually a minimum level PSU and I have had 2 already in my use burn out. Both now use external PSU supply.

The better of the two is of course the 80W unit and needs a good PSU ... I suggest a 12V 10A or a 15V up to 10A PSU... that way the PSU is well within its operating range and the charger can draw all it needs. The rate of charge is set by user according to battery pack and personal preference.

There is is one quirk with the Accucel though ... its power input connector is an XT60 and not the usual round din plug. So you need to be able to solder one or adapt the PSU power lead to accept.

But in all honesty - there are many chargers out there just as good .. some with built in PSU if you do not want to fuss around sourcing one. You can get SkyRC chargers of 60W and up with built in power supplies ...

BUT IMPORTANT : You must get a charger that has LiHV capability ... not just LiPo. Most of the later models have this - but check the specs carefully as the standard B6 does not.

Finally always keep the DJi charger handy. If you ever discharge your battery too low ... then only the DJI charger will charge it ... because at 3.0v per cell, 12v total - the protection circuit cuts in and you cannot switch on to connect your lipo charger. Only the DJI brick will work then.

Nigel

 

[frankgf321]

OK Frank ...

First the Accucel comes in various forms - with the 50W and 80W being the common ones. The Accucel is best bought from Hobby King at $34 instead of Amazon $47 ..... The only factor then is location and which warehouse of HK you buy from. They also need a power supply.

I do not advise buying a charger that has power supply built in, its usually a minimum level PSU and I have had 2 already in my use burn out. Both now use external PSU supply.

The better of the two is of course the 80W unit and needs a good PSU ... I suggest a 12V 10A or a 15V up to 10A PSU... that way the PSU is well within its operating range and the charger can draw all it needs. The rate of charge is set by user according to battery pack and personal preference.

There is is one quirk with the Accucel though ... its power input connector is an XT60 and not the usual round din plug. So you need to be able to solder one or adapt the PSU power lead to accept.

But in all honesty - there are many chargers out there just as good .. some with built in PSU if you do not want to fuss around sourcing one. You can get SkyRC chargers of 60W and up with built in power supplies ...

BUT IMPORTANT : You must get a charger that has LiHV capability ... not just LiPo. Most of the later models have this - but check the specs carefully as the standard B6 does not.

Finally always keep the DJi charger handy. If you ever discharge your battery too low ... then only the DJI charger will charge it ... because at 3.0v per cell, 12v total - the protection circuit cuts in and you cannot switch on to connect your lipo charger. Only the DJI brick will work then.

Nigel

Thanks Nigel!! I really feel like I've been to class! Since LiPo batteries are a real investment I don't wish to skimp on taking proper care of them. I intend to purchase one like yours or very similar. I have soldering capability, but I think there are snap-on adapters that you can buy instead. By the way, I'm flying a P4 standard instead of a P3 and assume the Accucel 6 will handle those batteries as well. Once again--thanks!!

Frank

 

[pe9999]

We use a battery inverter and dji original charger for charging the battery at the job site

 

[solentlife]

There are no snap on connectors like XT60 unfortunately.

To be honest - if you are only going to fly the DJI - then stick with the DJI charger. Because of the DJi battery design - there's no real benefit to using another charger. Except you get to see actual figures during the charge. If you are considering branching out into more mainstream RC .... cars / boats / planes / heli's etc. - then the LiPo charger is then needed, but not if only DJI.

ACC 6 80W charger $35 + shipping .... lets assume $10 .... $45
Power supply to run it assume about $15 ... so now we have spent $60 ..... plus of course the solder and XT60 plug ..

My original answer here was based on the OP asking if it was possible.

Nigel

 

[frankgf321]

There are no snap on connectors like XT60 unfortunately.

To be honest - if you are only going to fly the DJI - then stick with the DJI charger. Because of the DJi battery design - there's no real benefit to using another charger. Except you get to see actual figures during the charge. If you are considering branching out into more mainstream RC .... cars / boats / planes / heli's etc. - then the LiPo charger is then needed, but not if only DJI.

ACC 6 80W charger $35 + shipping .... lets assume $10 .... $45
Power supply to run it assume about $15 ... so now we have spent $60 ..... plus of course the solder and XT60 plug ..

My original answer here was based on the OP asking if it was possible.

Nigel

OK. I see your point. I have been to the Hobby King site and selected the same Accucel Charger & a power supply unit (I think it cost about the same as the charger, but I may have over speced). I haven't placed the order yet, however. I'll hold off and make the decision in a couple of days. I am assuming that you don't believe that the Accucel does a better job of charging or that it won't make my batteries last any longer.

Thanks anyway! It's really helpful to learn as much of this technical stuff as possible.

Frank

 

[solentlife]

The problem is DJI.

They have decided to take away control of charging from the user. They supply a PSU type charger that basically thumps out 17.5V regardless. The battery internal board then regulates the charge rate in.
To put it simply - the DJI charger is a CV unit and mimics the CV state of a LiPo charger but without the superior balancing ability.
The balancing is reported to be done by the battery board - but this is not actually 100% correct as the board shuts off at total 17.4V ... so any balancing is shortlived.

The LiPo charger .. Procharge ... Imax ... SkyRC ... Accucel ... whatever brand - is a twofold unit. It not only provides user settable amp rates / cell number ... but also the ability to balance fully cells. That's where the problem appears ... DJI do not allow you access to the balance lead. That's tucked inside the battery case and plugged into the board for telemetry purposes.

So is the Accucel better ? Yes and No.

Yes : Because you can see the charge figures as its working ... voltage, amps, time charging, mA's in ... and it shuts off when it reaches full charge.

No : Because you cannot use its balancing function to get the very best out of the pack.

So as I suggest ........... if there is no intention to have any other model with standard format LiPo's - then a LiPo charger such as the Accucel is money you can save.

In my opinion if a person is staying with DJi and the P3 series ........ and has multiple batterys - then best buy is :

https://www.amazon.co.uk/dp/B015B86ULI/?tag=rc-toys-21

I have one and its excellent. I agree that it has no display ... but it charges 3 batterys and Controller SIMULTANEOUSLY in the same time your DJi charger only does one battery !! ... unlike the grossly overpriced and sequential rubbish others sell !!

Nigel

 

[frankgf321]

The problem is DJI.

They have decided to take away control of charging from the user. They supply a PSU type charger that basically thumps out 17.5V regardless. The battery internal board then regulates the charge rate in.
To put it simply - the DJI charger is a CV unit and mimics the CV state of a LiPo charger but without the superior balancing ability.
The balancing is reported to be done by the battery board - but this is not actually 100% correct as the board shuts off at total 17.4V ... so any balancing is shortlived.

The LiPo charger .. Procharge ... Imax ... SkyRC ... Accucel ... whatever brand - is a twofold unit. It not only provides user settable amp rates / cell number ... but also the ability to balance fully cells. That's where the problem appears ... DJI do not allow you access to the balance lead. That's tucked inside the battery case and plugged into the board for telemetry purposes.

So is the Accucel better ? Yes and No.

Yes : Because you can see the charge figures as its working ... voltage, amps, time charging, mA's in ... and it shuts off when it reaches full charge.

No : Because you cannot use its balancing function to get the very best out of the pack.

So as I suggest ........... if there is no intention to have any other model with standard format LiPo's - then a LiPo charger such as the Accucel is money you can save.

In my opinion if a person is staying with DJi and the P3 series ........ and has multiple batterys - then best buy is :

https://www.amazon.co.uk/dp/B015B86ULI/?tag=rc-toys-21

I have one and its excellent. I agree that it has no display ... but it charges 3 batterys and Controller SIMULTANEOUSLY in the same time your DJi charger only does one battery !! ... unlike the grossly overpriced and sequential rubbish others sell !!

Nigel