I'm wondering how to keep the batteries of my P4P+ good. I think I've read somewhere that after a certain amount of charges you should auto discharge them. But I dont know how many charges are recommended with these type of batteries. So any tipps to keep my batteries as good as possible?

Thanks a lot

Ray

Hi, thanks for reaching DJI Forum. We do appreciate bringing this query. Keep it in a water-free environment and set an auto-discharging time. The discharge rate of the Phantom 4's Intelligent Flight Battery is 5C while battery should be fully charged and discharged once every 3 months to keep it activated.

So just to understand correctly. After 5 times charging the battery I should discharge the battery fully?

How do I do that manually, btw?

Ray_Drone_Pilot Posted at 2018-7-16 12:49
So just to understand correctly. After 5 times charging the battery I should discharge the battery fully?

How do I do that manually, btw?

No, it's not 5 cycles.

You don't have to worry about this at all.
Manually discharging batteries periodically is something from the past.
DJI's smart battery circuitry takes care of battery management for you.

The battery will auto-discharge to 50% storage level by itself a certain number of days after charging if not flown.
You can set the number of days from 1-10 to suit your flying pattern.

The principles to be concerned about are to avoid leaving a battery fully charged for too long and to avoid leaving a battery discharged to low level for too long.

Deep cycle, is the way to extend battery life, and make the drone fly faster...not!!  haha


RedHotPoker

The DJI software actually prevents a battery going below 3V per cell ... AVERAGE over the cells. Any LiPo going below 3V a cell will suffer damage ... 2.8V on a cell is the lowest and will certainly cause damage. In fact it will be hard for even the DJI charger to get that cell back up again ... if overall voltage is below min - then the charge control board defaults out.

Deep discharging a LiPo has no benefit whatsoever for the cells themselves - BUT it will reset the chip counter which gets out of step with charge / use / charge of battery over time. To reduce this happening - its well to fly your battery for a long flight time occasionally instead of the usual short jobs. Flying till you get low battery warning is good enough, making sure you are close to home point of course !!  Most people I think leave that warning set at 30% .. which is a good figure.
You can unplug that battery at 30% and put to store without doing anything ... just check it a few days later to make sure its not getting too low .. if so - charge it up and let the batterys Board sort out the discharge ..

Nigel

Thanks for the responses. I think I understand but now when I leave for a long time (could be 2 months or so) should I store the batteries fully charged or 75% charged or 30% charged? Like all batteries if you don't use them they will slowly loose theire charges too.

I just deep cycled my 3 batteries for the second time, using the 3 month rule as a guide. As Nigel stated, the batteries turned off before reaching 3 volts per cell. My experience was around 13.09 volts total for all 3. I flew until the 30% low battery alarm sounded, then came back and landed. Took off again and hovered to mark a known home point. At 15% it tried to RTH and I was able to cancel. At 10% it forces landing but I was able to keep it aloft using the throttle. At 2% I caught it held the throttle up just to keep the motors running until the battery turned off. After an hour of cooling in the air conditioning I charged them to 100%. The next day I flew so each battery was storage ready at 40% to 50%.

There are many opinions about how to maintain LIPO batteries. I use this method as this is how I interpreted the manual.

Jeff

So this deep cycling means draining the battery till about 2%? I don't see what the purpose of the is but ok. I do understand now that it is good to store them between 40  and 50 percent.

Thanks for all the input much appreciated!

Ray_Drone_Pilot Posted at 2018-7-17 02:59
Thanks for the responses. I think I understand but now when I leave for a long time (could be 2 months or so) should I store the batteries fully charged or 75% charged or 30% charged? Like all batteries if you don't use them they will slowly loose theire charges too.

Two months is no problem.  I would deliberately fully charge them, and leave them fully charged and let the auto-discharge take them down to a safe storage level.  

And as a second thought how a bout the controller btw?

Mark The Droner Posted at 2018-7-17 03:21
Two months is no problem.  I would deliberately fully charge them, and leave them fully charged and let the auto-discharge take them down to a safe storage level.

Thanks this makes fully sense

Mark is correct ... set the Auto Discharge to what you think is good for your use. Charge up fully and set on the shelf in cool place.

2 months should be OK - but I would be checking thereafter levels .... if I saw 1 full on LED + 1 flashing LED ... I would then full charge again and return to shelf for Auto Discharge to work.

Many people misunderstand the fundamental difference of a DJI battery to other LiPo's ...

Normal LiPo's require you as user to look after the charge / discharge / storage and general life. This is why Programmable Chargers appeared. We could charge at user set rates, we could charge different cell counts,we could put battery to storage from any point of charge. Note LiPo storage is recc'd to be from 3.70V up to 3.85V per cell.  That equates to 25 to 55% approximately. battery techs I know advise to store in the lower 35% range ...
But a DJI battery even though its a 4 cell LiPo (LiPo High Voltage actually .... usually termed LiHV) has a charge control board with telemetry data transfer fitted to front end. This is what provides the LED indicators etc. This takes away about 80% of users access to cells and is designed to :

1. Stop overcharging
2. Stop over discharging
3. When left idle and not touched it will - IF THE CHARGE LEVEL IS APOVE 50% - start auto discharge at the time set by user. 10 day factory default is too long ... I advise 2 - 3 days ...

So in effect the DJI battery is produced for those less knowledgeable about LiPo maintenance. Charge up ... use .... store.

If you take battery down below 30% in flight - then I advise you fully charge - then store - let the Auto Discharge do its work. If you stop flying at 30% or above - then if you expect to fly within the next week - just store until just before you need and charge then. There is no need at all to charge up to 50% ...

OK - myth busting :

1. If you charge up a battery and have auto discharge at 2 or more days ... it is NOT true that battery will still be full charged after 1 day standing. Low Self Discharge happens to all batterys and you will lose 1 or 2% charge ... I usually switch on battery and plug in charger before flight to put back that small amount. If you do not switch on - charge will not happen. Board on front of battery defaults at 93% stopping any top-up charge - switch on battery and charge works.
2. Deep discharge recovers or rejuvenates LiPo ... total BS ... what happens is that charge control board resets its counter. The battery has in no way been repaired or rejuvenated - LiPo damage is IRRECOVERABLE ... IRREPARABLE.


Nigel

Ray_Drone_Pilot Posted at 2018-7-17 03:21
And as a second thought how a bout the controller btw?

The controller is powered by a lipo but not an intelligent lipo.  Still - you don't want to leave it fully charged and you don't want to leave it under-charged.  Personally, in your case, I would charge it to around two full lamps and third lamp blinking OR three full lamps.  Others might have other opinions...

You have an advantage with the Controller. LiPo's can still deliver moderate power even when damaged by long periods of full charge.

The amps / power delivery is governed by Internal Resistance .... as it increases - the voltage drop to supply amps increases .. amps rise to compensate ... as your power requirement is in WATTS.

With a flight battery - it has to supply serious WATTS and in that means Volts - Amps. So if Internal Resistance is high - the battery will perform poorly and you will have short flight time ... getting worse every time you use it.

But a Controller only needs low amps and this then does not cause Internal Resistance to create such voltage drop ... result is the battery works and you fly. The average RC Tx will provide somewhere between 8 and 11 hours useful control time. The P3S controller uses a 2600mAh 1S LiPo and is rated at 600mAh demand. In theory that means 3.5hrs use time allowing for 20% balance left (1 full LED). I actually got more than that but should the time to that 1 LED drop ... then it means battery is on its way to the bin !!  P3A controller as it uses a different control setup, actually can charge tablet if req'd is with 6000mAh 2S LiPo and rated at 1.2A demand. In theory that means 4 hours use allowing 20% balance to remain. P3P is same as P3A ...

For those who wish to maximise controller battery can put in practice a storage regime ... basically have 2 LED lit and that should be good. Periodic checks to make sure charge is still there ... charge up if not.

Nigel

I left my drone and three batteries behind when I left for Russian waters.  Aprox  8 months.   Really didn't want to use my drone on steel vessel.  When I returned home The batteries were down to 1 light.
R/C was down to 1 light.
At the time I had my batteries set to discharge after 3 days.
So I get home....charge batteries and they were fine.  R/C tool about 4 hours to charge fully.
Hooked everything up and got notice to update.   That went well.
As soon as R/C charged I went flying.
So that is how long term storage went for me.
I have Lipo's for my Heli's but they went south for good.
I really like DJI batteries.

Sorry for the late response guuys but thanks a lot for all your input! I was out of any connection with the WWW so could not see all the messages.

Grtz

Ray

Hehehe,   there is certainly no shortage of posts or advice re battery maintenance.  I would personally like to see more input from DJI Techs on the subject - beyond "Refer to page XXX in your manual"

Manxmann Posted at 2018-7-23 01:23
Hehehe,   there is certainly no shortage of posts or advice re battery maintenance.  I would personally like to see more input from DJI Techs on the subject - beyond "Refer to page XXX in your manual"

You never see any input from DJI tech people here.

Labroides Posted at 2018-7-23 01:49
You never see any input from DJI tech people here.

Probably because of the 'flak' they would have to endure !



Nigel

I do more or less as Jeff explain in #8, doing what the producer recommend would assure they can not blame you in case that something go wrong at some point.
The reason for doing the deep discharge cycle is to make sure the cells are well balanced and to have the builtin controller board learning the behavior of the cells in order to provide a more correct percent reporting to the user.

Labroides Posted at 2018-7-23 01:49
You never see any input from DJI tech people here.

Discretion is a virtue,  I am going to be virtuous (for once ! )  and bite my tongue.

Manxmann Posted at 2018-7-24 01:47
Discretion is a virtue,  I am going to be virtuous (for once ! )  and bite my tongue.

It's just the way this forum is run.
DJI tech people never have any input here ... and the DJI people that are here have very little expertise in anything relevant.
If other members can't answer enquiries, they go unanswered.

Labroides Posted at 2018-7-24 02:10
It's just the way this forum is run.
DJI tech people never have any input here ... and the DJI people that are here have very little expertise in anything relevant.
If other members can't answer enquiries, they go unanswered.

Appreciate that there is sooo much expertise out there in the communities.
There is no substitute for hands on experience IMHO