Scary flight today. Over a lake and with 55% battery remaining get a 'critical low battery' warning and P3A switches to 'Landing' mode. Scary since over water (see log screen). Fortunately was high and able to bring to the shore.

Battery status indicates 19 cycles and 100% battery life. Battery was fully snapped in place when landed. Can I trusted this battery? Advise?

What percentage do you have the battery warnings set at in the DJI Go app?

Upload your flight log to healthydrones website and check the battery cell's. http://healthydrones.com/

Rigworker Posted at 2015-10-18 21:28
What percentage do you have the battery warnings set at in the DJI Go app?

10% critical, 30% warning

LTDtim Posted at 2015-10-19 03:36
10% critical, 30% warning

How very strange. And scary. Did you manage to fight the landing mode?
See my thread for a similar story, water and critical battery landing at 21% power
http://forum.dji.com/thread-33590-1-1.html

Rocket_Aus Posted at 2015-10-19 03:30
Upload your flight log to healthydrones website and check the battery cell's. http://healthydrones.c ...

And check the rest of the flight data. Lots of useful stuff there such as winds.

Rigworker Posted at 2015-10-18 21:28
What percentage do you have the battery warnings set at in the DJI Go app?

I have the same question. I think mine was at the same point when it was new. I moved it down to 30%.

Rigworker Posted at 2015-10-18 21:28
What percentage do you have the battery warnings set at in the DJI Go app?

I have the same question. I think mine was at the same point when it was new. I moved it down to 30%.

Hi,

There are quite a few of these complaints and actually I have experienced the same, auto landing at 62%. I just copy and paste my oppinion from another thread.

Short version: Always recharge your batteries just before you wanna fly (1-2 days maximum) and always start with fully charged batteries (100%).

Long version:
I think everybody of us is aware of how a Lithium battery should work and should be treated but I also came to the conclusion that this does not fully apply to the Phantom battery, for whatever reason. Maybe because the battery for an aircraft is much more complex than a battery for a cell phone, maybe DJI technology is not sophisticated enough, who knows, we can start a long list of speculation again.
Fact is: it just doesn't seem to work as it does with a cell phone. When my cell phone indicates 60% or 50% or even 20% battery, I still make phone calls. That apparently does not work with the Phantom.

It looks like you really should start with always 100%, with one hour breaks probably tolerable. I started with 65% and after one minute I got a critically low power with auto landing at 62%. I didn't crash as I had the weird feeling that this might happen and the Phantom was very close and I was still able to steer the Phantom back to where I was.

My learning: I would fly a battery with 50% left only if I have a one or maybe two hour break. Two hour break I would probably start to be very careful. In any other case, less power left or longer breaks, I would leave the battery and recharge it when I know I will fly that battery within the next 24 hours.

Again, we can discuss if that is how a lithium battery should work and we probably get a lot of answers saying no. But it's just the way it is.

DroPro Posted at 2015-10-19 10:25
Hi,

There are quite a few of these complaints and actually I have experienced the same, auto landin ...

The batteries for phantoms are not normal Lithium batteries they are Lipos (Lithium Polymer) they are much more complex to deal with than normal Lion or even Life batteries.

Here is a really good page with lots of information about Lipos:
Lipo Info

Here is a writeup I did on another thread on this board:

Lipos often puff when overly discharged. I have over a hundred Lipos and I usually retire them once they puff. I certainly would not fly anything expensive with a puffed Lipo.

There is lots of information on the WEB about Lipos and care for them. DJI has simplified charging and balancing as well as storage.

Most Lipos are dumb and you have to do the balancing and storage yourself. There is even a recommended breaking procedure, and that is to only fly gently, no full throttle for the first 10 flights or so and don't discharge below 50% during the breaking period. This will help Lipos live longer and store full or close to full charge longer.

Another key trick to long life with Lipos is never discharge below 30%, I always land at 30%, my absolute limit is 20% any less then that and you may puff the Lipo and the life span will shorten. Personally I don't understand the 8% discharge DJI talks about. Maybe someone from DJI can comment here.

I typically get 500 cycles or more from my Lipos before retiring. Once they don't charge up above 85% or so I retire them. I always store lipos between 35% and 70%, never fully charged. Charge within 12 hrs of flying. If not used then fly them down to 50% to store, even just hovering in your garage if it is raining.

I doubt DJI lipos are different from most Lipos, so I use these procedures on my phantom Lipos.

This is the thread:
puffed battery

Downloaded the flight logs and uploaded into healthydrones.com (awesome site). Here are some of the results. Temp seems higher than normal. Battery was charged less than 12 hours before flight. Any ideas?

I had a similar issue where my P3P went into landing mode at about 40% remaining battery, except my error message wasn't critically low batter, it was "low voltage warning".  Have you ever got a critically low voltage warning with your trouble battery?  Apparently when you get a CLV warning the drone goes into landing mode but I was given the option to cancel landing mode and continue flying (to quickly bring it home).  When yours went into landing mode, did you have the option to cancel landing and resume flight control to bring it home?

On a side note... on a long distance flight I got a low battery warning at about 65% battery remaining, but it was "drone will return to home in 10 seconds" type of warning which (I think) was prompted by distance way from home rather than a battery fault, but just thought I'd throw that in.

Let us know what else you find out

No chance provided to cancel. I'm almost at the 20 cycles on the battery. Any opinions on whether the full discharge to 8% and recharge would help? Just not sure how to trust the battery again.

Westside Osprey Posted at 2015-10-19 23:50
The batteries for phantoms are not normal Lithium batteries they are Lipos (Lithium Polymer) they  ...

Thanks, didn't really know there is a fundamental difference between Lithium batteries and Lipos. So, we shouldn't drain the batteries. I also thought it might be useful from time to time, to extend the battery life. But it looks like it is not useful to go below 30%.

DroPro Posted at 2015-10-19 09:25
Hi,

There are quite a few of these complaints and actually I have experienced the same, auto landin ...

What are these "breaks" you speak of?

ag0n Posted at 2015-10-20 10:23
What are these "breaks" you speak of?

He means Fly to 50% -> 2 hour break -> resume flying from 50%.

As opposed to Fly to 50% -> 2 day break -> resume flying from 50% minus ???

That's an unknown for me.  I've seen mention of not doing that sort of thing, but I haven't had any battery problems at all and do fly short hops with low batteries that were stored in the case at 50% when testing settings, etc.

FYI, this flight was starting from a fully charged battery, charged less than 12 hours before flight and kept at room temp. I assumed that one of the cells dropped Voltage and that initiated the error. But the flight logs don't support that. DJI does recommend the full discharge cycle at 20 charges. I'm I reading that that is not advisable?

Same thing here. Happened at 46% over a lake. I had no option to cancel but I was high enough to nudge it over to the neighbouring field. Here is my thread.