Are those intelligent batteries stupid?

[Andy9]

Or should I say that the programmed algorythm is stupid.
This was discussed several times that if the voltage of bat.cells drop under the defined level the batt will shut off. The explanation is that in this way the batt is protected from damage.
But who should do such wise action if the drone is in flight. Is the battery which is protected or should be the drone? If the drone is crashed to pieces, a protected batt is of no use anyway.
Much better solution would be if the motors gradually loose the power so it will land when this happened.

 

[Deleted member 62848]

Agree I lost a p4 due to battery shut down,,those batterys to clever for their own good,that's artificial intelligence for ya,the batterys dont need to be clever, they just need to charge and discharge when used like a normal batt,the drone should be in charge of what's going on,not the batt,,this has ripped my underwear for years,I still dont trust them

 

[DoomMeister]

Sort of like the fuel tank on a passenger jet controlling whether the propulsion system still works because it doesn’t want to run dry! When you hit 15% fuel remaining they shut off the flow to the engines?

 

[WV. Rootman]

People love to quote," knowledge is power " If you don't know how to use that power, you can blow yourself up. Lol. Intelligence does not denote
wisdom. I think that is the case here.
(Removed by moderator-Rule 13)

 

[quaddamage]

I can't say I understand that fully, but it would seem that DJI really acknowledged that, and did some modifications to the battery in latest drones. Everything Mavic Air + has the mechanisms within the battery altered to what the manufacturer (Texas Instruments) normally provides.

I've seen speculations that some conditions on turning off power immediately are eliminated. It can still do so, ie. if the cells temperature is so high it's going to burst into flames any moment.

But I'm pretty sure if such situation happens, the battery won't turn on any more after you finish the flight.

 

[DoomMeister]

Gosh are you referring to batterys shutting off at 15% or jet engine fuel shut down,glad I dont go on those things lol,shouldn't the batterys aheed to dji batt low warning or critical setting before it auto land from low power ,my brain functions are asleep but trying to make sense of that,I guess all the smart settings must be off since they predict the flight ?
I think I confuse myself now ha

Just commenting that the battery should not be able to shutdown to save itself if the aircraft is airborne. The ability to do that would be akin to the fuel tanks on an airliner determining when to halt flow to the engines.

 

[Billie Nelson]

Days ago my Phantom3S arrived from one of many previous fully autonomous 6-mile round-trip Litchi missions with a battery level inching below 20%. The instant I toggled the controller switch to invoke my usual textbook smooth glide-slide landing approach, the engines shut off, the lights died, and my diabolical nemesis, gravity, took ruthless control of the craft at 140 feet AGL.

Prior to stumbling on this discussion topic, it never occurred to me that a DJI flight battery could abruptly shut down in low charge conditions mid-flight by design. I was aware that the Phantom3S was programmed to go into a forced descent and autolanding whenever battery power dipped below 10%, but this is the first time I have heard of this "sudden battery death syndrome", which I now realize in retrospect may have been the cause of my late Phantom3S' terminal impact with concrete from 140 feet up in the air.

 

[captainmilehigh]

Sort of like the fuel tank on a passenger jet controlling whether the propulsion system still works because it doesn’t want to run dry! When you hit 15% fuel remaining they shut off the flow to the engines?

I would hope not. Would make my job a bit more difficult. ...[emoji15]

 

[DoomMeister]

I would hope not. Would make my job a bit more difficult. ...[emoji15]

That as a tongue-in-cheek statement in relation to a smart battery shutting off in flight to save itself and sacrificing the aircraft.

 

[captainmilehigh]

That as a tongue-in-cheek statement in relation to a smart battery shutting off in flight to save itself and sacrificing the aircraft.

Oh yeah, I knew what you meant. [emoji16] No problem. [emoji106]

Just never have heard of a smart battery shutting off by itself, to 'save' itself. Mine have always performed as programmed in 'settings'.

Granted some of my batteries are a bit older and drain faster than the newer batteries, but that's to be expected.

 

[Andy9]

Let me clear something up. Of course there are many warnings (acoustic and visual) which informs you that the batteries are going low and then at last the drone go to autoland mode. That's OK.
But I was talking about the voltage of cells. This is not absolutelly comparable to the percentage of remaining batt.
If you have one cell in your batt. that is not so good as others then if the voltage of this cell falls under I think 3 V or something like that, this would be the shutoff point even if your batt. shows more than 25% of remaining power. That's the problem. And this is why it is so important to start the flight with fully charged batt.

 

[skymonkey]

I have my C2 button toggled to my battery view and I check it intermittently while flying. I check voltage per cell and battery temperature as it does get hot down here. It’s a habit like checking your car gauges when you drive.

 

[Andy9]

Yes, t is always useful to check the batteries during the flight. Especially check if any cell behaves abnormal.

 

[Deleted member 62848]

Yeh simple to set up to,I never thought of this
If my drone dont sell I be doin this
Great idea,,I relied on litch lady feedback

 

[Billie Nelson]

The mystery deepens. Here is my shortlist of possible reasons that Phantom drones drop like rocks.

1. Sub-standard non-OEM batteries that shut off abruptly under circumstances not as yet fully understood.

2. Batteries made by DJI and other after-market vendors, that shut down if one of the cells malfunctions.

3. Failure to clean the battery terminals of the drones, per the recommended service intervals in AirDataUAV.

4. An improper entry made in the DJI Go app, regarding the percentage of charge at which a battery should shut down.

With my replacement Phantom3S inbound and due for delivery today or Monday, I sure hope I can learn more about this sudden battery death syndrome, to stop it from happening again.

 

[Andy9]

I like this 'SBDS'abbreviation. Should become a standard in drone language.

 

[Jag71]

On a similar note I once saw a $500,000 turbine helicopter drone fly. During one test at around 100ft up the load became too much and the turbine shut itself down due to an over temperature condition, in order to protect itself. They helicopter then crash landed and I am sure the shock load to the turbine would have done substantial damage at best, and destroyed it at worst. I am all for giving the pilot big red warnings, alarm bells etc in such a situation, but let the pilot choose to destroy the engine whilst landing the aircraft successfully if they choose. My 2 cents worth.

 

[Twilightdrone]

Yes, t is always useful to check the batteries during the flight. Especially check if any cell behaves abnormal.

I wish this thread had been a week earlier!! ( After watching my ac fall out of the sky during it's own induced RTH, the second pic shows a bad cell - could this have been the cause? are these Batteries now repairable or disposable? ie should I send it along with the ac to the repair centre, please?

 

[Deleted member 62848]

I wish this thread had been a week earlier!! ( After watching my ac fall out of the sky during it's own induced RTH, the second pic shows a bad cell - could this have been the cause? are these Batteries now repairable or disposable? ie should I send it along with the ac to the repair centre, please?

Oh man feel your pain there,,still under warranty, battery or amount of charges probably expire before the year is up but certainly shows that cell went bad,,,mine were good but had same outcome,,I still have the culprit batt and it still good but wont use it,,ugly outcome,I unsure what say but you be in for new battery if a repair shop does it but dji might cover if drone within that 1 year warranty...mayby it sensed the loss of volt in that cell since it yellow

 

[Twilightdrone]

Oh man feel your pain there,,still under warranty, battery or amount of charges probably expire before the year is up but certainly shows that cell went bad,,,mine were good but had same outcome,,I still have the culprit batt and it still good but wont use it,,ugly outcome,I unsure what say but you be in for new battery if a repair shop does it but dji might cover if drone within that 1 year warranty...mayby it sensed the loss of volt in that cell since it yellow

(you're up early! Must be the new 'travel bubble'!! I'm in WA)
Nah - batteries are 4 years old and that dud was operating perfectly that flight until it got down to a certain level and instead of landing automatically, it shut down the motors at height.
If it's better to replace the batteries then maybe I should send the remote as well, as it is only charging to 75% ? Or are they a DIY job?