I would check post #6 and post #19

Well, thanks for giving us one more thing to worry about, lol.  Good job narrowing it down.

ALABAMA Posted at 2018-4-11 15:20
Well, thanks for giving us one more thing to worry about, lol.  Good job narrowing it down.

Lol i do my best

Just so random how it cuts power and the battery lights remain on.

I think it was brought up in this thread that the battery should not be flown anymore. It is being retired to be used for updates/ground work/repairs, no flights.

Linuxglobal Posted at 2018-4-11 15:00
Another follow up, my p4p is being used in the field at the moment so i had to improvise as I had no P4 batteries around.

I had a spare p4pro drone, plugged in the crash victim battery and guess what ..... it failed in the p4p as well. Just randomly cut out, lights on and everything.

Scary stuff. I couldn’t catch the LEDs in the video at the moment it shut down in both videos. Do they stay on, or blink off?

Jeff

Jeff Millard Posted at 2018-4-11 15:55
Scary stuff. I couldn’t catch the LEDs in the video at the moment it shut down in both videos. Do they stay on, or blink off?

Jeff

Hi Jeff, its not the battery leds, the drone leds turn off, but the battery leds stay on the whole time, its literally like a power flash. The error must be inside the battery circuit board / cell balancing. I was observing the cells as the power failed and cell 4 seemed to show a bit more power drop than the others.

I thought at first it was a cpu error / drone internal wiring but its a certain issue with the battery now that 2 other p4p drones show the issue.

I will be getting my p4p sometime this weekend from my gf's filming so I can fire it up.
Im going to 3D print some sort of cage to strap the drone done to avoid too much of a height when it loses power.
Video 1: 14/15 second mark when the drone falls down hard
Video 2: focus on the red motor light, turns off around 57/58 second point. Just goes out while being fully lit otherwise.

The battery leds never turn off during any of the failures.

I may hard wire a volt gague on the back of the battery during these tests to see what spike/drop occurs to make the drone reset.
I am guessing the battery error is either due to age, or battery abuse and improper charging/discharging. It seems to be very good and reliable 100%--80% then around 40-50% when my buddy had the crash, it is within seconds that it falls.

P4P replacement battery en route it would be nice if DJI chimed in on how to test these batteries. THe usual press and hold shows 4 flashing leds for the life lol.

It would not be a good idea using it for FW upgrades, calibrations perhaps but not any upgrades. Should it die during the upgrade you could fry a lot more than good is ...
I would open it and check the soldering work.

Well. That was interesting. You don't have a way to discharge the battery  outside the drone and at the same time measure the voltage? Even better load it with an adjustable load and watching the voltage?

Håkan K Posted at 2018-4-12 09:40
Well. That was interesting. You don't have a way to discharge the battery  outside the drone and at the same time measure the voltage? Even better load it with an adjustable load and watching the voltage?

Actually it is possibile. without A/C mains connected to the charger you can pull out 17.2v from the RC charging plug (+ at center pin, - on outside) when a full charged battery is connected and turned on.

KedDK Posted at 2018-4-13 01:36
Actually it is possibile. without A/C mains connected to the charger you can pull out 17.2v from the RC charging plug (+ at center pin, - on outside) when a full charged battery is connected and turned on.

I will have to come up with a rig since its a very odd battery fail. Seems to work sometimes and I fully drained it at idle state (motors idling slowly but not taking off).

I tried spinning motors without props, and still no failure.

It seems to happen just as it is in flight. Perhaps vibration of the battery/aircraft or looks cell connection ?

Thanks again for all the input guys. New p4p battery on the way, lesson learned for sure ... crash = junk battery.

Vendex Posted at 2018-2-28 22:51
Why takeoff battery is not at 100% ? Just learn to charge this batteries

When you mentioned no lights followed by the battery was out of it when you found it... I am betting the battery was not fully installed.