My Phantom 3 Advanced refused to take off yesterday - The DJI Go app complained that the battery temperature was too low. The indicated battery temp was +13 degrees C, and I understand it wants it to be above 15 degrees. What nonsense is that?? 13 degrees on the plus side is not cold - battery capasity may be a bit lower of course, but so what? A LiPo battery works perfectly fine at 13 degrees (and it will warm up during use), and I'm sure the software must be intelligent enough to adjust the available flying time left accordingly (since it's pretty clever otherwise).


Is there any way I can override this silly limit?

Another day I also experienced that the app suddenly warned about "critical battery / low temperature" or something, and tried to land the Phantom out on the ice covered fjord. Remaining battery indicated more than 80%! Luckily, I managed to get the aircraft back by increasing the throttle considerably, and it hovered perfectly fine above the landing spot when I got it back (I don't like walking out on the fjord ice - you never know if it's safe.). What on Earth are the DJI engineers thinking when they program the thing to do such stupid things?

(BTW, I was out driving my electric car yesterday at minus 10 C, without any battery preheating. Range is of course lower, but no problems otherwise.)

That probably saved your phantom.  Don't complain, be thankful.

It is a fact that battery capacity is severely reduced in low temperatures. This applies to ALL batteries. Therefore DJI are protecting users from losing thier aircraft if the battery cannot deliver its full capacity.  The solution is simple, warm your battery before you fly, and let it hover after starting for a short time to increase the battery temperature.  

Geebax Posted at 2018-2-5 13:52
It is a fact that battery capacity is severely reduced in low temperatures. This applies to ALL batteries. Therefore DJI are protecting users from losing thier aircraft if the battery cannot deliver its full capacity.  The solution is simple, warm your battery before you fly, and let it hover after starting for a short time to increase the battery temperature.

Yes, it is surely reduced at low temperatures, but by no means severly at +13 C. I also have a self assembled F550 Flamewheel hexacopter, where there is no onboard software or app that monitors the battery temperature. I have flown this a lot in cold weather, and at those kinds of temperatures, the battery capacity reduction is barely noticeable.

Also I can't see how DJI is "protecting" me by suddenly trying to land the Phantom at present position when it's perfectly able to fly....

fans43eed3c2 Posted at 2018-2-5 14:03
Yes, it is surely reduced at low temperatures, but by no means severly at +13 C. I also have a self assembled F550 Flamewheel hexacopter, where there is no onboard software or app that monitors the battery temperature. I have flown this a lot in cold weather, and at those kinds of temperatures, the battery capacity reduction is barely noticeable.

Also I can't see how DJI is "protecting" me by suddenly trying to land the Phantom at present position when it's perfectly able to fly....

There is no way technically to detect a reduced battery capacity due to low temperatures, But because the DJI aircraft are frequently flown by people who are completely clueless in terms of these things, they have responsibly taken the decision to try and safeguard anyone who might be underneath the aircraft when a cold battery craps out.

You might find this video helpful.  If you get bored, skip ahead to 6:56.

Geebax Posted at 2018-2-5 14:07
There is no way technically to detect a reduced battery capacity due to low temperatures, But because the DJI aircraft are frequently flown by people who are completely clueless in terms of these things, they have responsibly taken the decision to try and safeguard anyone who might be underneath the aircraft when a cold battery craps out.

Well, my battery powered car calculates and displays remaining range continuously, and does indeed take temperature into account. In the summer (around 20 deg C), it says about 220-230 km when I start out with a fully charged battery, while yesterday, when it was minus 10, it showed about 170 km. The DJI software is very sophisticated, - it even calculates "bingo fuel" - heading home automatically when battery capacity and distance out dictates a return. But initiating a landing when the battery is at 80% and it's just a few hundreds meters away? That appears more like a software bug to me...  I really can't see that it should be any problem to include temperatures in the calculations?

Thanks for the video Mark

Good vid.  Everyone should watch.

fans76a55fe2 Posted at 2018-2-5 14:53
Well, my battery powered car calculates and displays remaining range continuously, and does indeed take temperature into account. In the summer (around 20 deg C), it says about 220-230 km when I start out with a fully charged battery, while yesterday, when it was minus 10, it showed about 170 km. The DJI software is very sophisticated, - it even calculates "bingo fuel" - heading home automatically when battery capacity and distance out dictates a return. But initiating a landing when the battery is at 80% and it's just a few hundreds meters away? That appears more like a software bug to me...  I really can't see that it should be any problem to include temperatures in the calculations?

DJI do take the temperature into consideration when calculating remaining flight time, what makes you think they don't?
There is little point in comparing your electric car with a Phantom, for a start, your car does not fall out of the sky if the battery is exhausted, and your car has a single battery that is fixed in the car, whereas the Phantom can swap batteries, making it a bit more complicated to figure out reliably the remaining capacity.

Mark The Droner Posted at 2018-2-5 14:46
You might find this video helpful.  If you get bored, skip ahead to 6:56.

https://www.youtube.com/watch?v=2ue3tXm-GtQ

Thanks, interesting video. That the voltage drops when demanding a lot of power is known, and both my car and the Phantom have built in protection for that, automatically decreasing the power if the demand is too high. (The car also takes battery temp into consideration, and limits the allowable power output when the battery is cold.)

The automatic thrust limiting function in the Phantom is a sensible feature. I still can't see the need for the somewhat "hysterical" immediate landing mode at intermittent voltage drops however (at least it should be activated at really critical levels only), since it will still be perfectly able to fly as the power demand is decreased. My Flamewheel has a DJI Naza flight controller, and I'm grateful that automatic landing at present position when voltage goes below a selected value is an optional feature you can program or not!

It is of course very good advise to try to keep the batteries warm, by having them close to your body for example, but to maintain them at 25 degrees C, as recommended by DJI, will most often be impossible unless you live in a tropical climate. Their engineers must live in a pretty warm country to consider +15 C as "cold".... :-)

Geebax Posted at 2018-2-5 15:54
DJI do take the temperature into consideration when calculating remaining flight time, what makes you think they don't?
There is little point in comparing your electric car with a Phantom, for a start, your car does not fall out of the sky if the battery is exhausted, and your car has a single battery that is fixed in the car, whereas the Phantom can swap batteries, making it a bit more complicated to figure out reliably the remaining capacity.

It's not me who thinks that... As I said, I would find it very natural that the Phantom's sophisticated software takes temperature into account. As for falling out of the sky, I'm just  trying to say that I find it quite unnecessary that they are programmed to stop flying when they really don't need to.

fans76a55fe2 Posted at 2018-2-5 16:43
Thanks, interesting video. That the voltage drops when demanding a lot of power is known, and both my car and the Phantom have built in protection for that, automatically decreasing the power if the demand is too high. (The car also takes battery temp into consideration, and limits the allowable power output when the battery is cold.)

The automatic thrust limiting function in the Phantom is a sensible feature. I still can't see the need for the somewhat "hysterical" immediate landing mode at intermittent voltage drops however (at least it should be activated at really critical levels only), since it will still be perfectly able to fly as the power demand is decreased. My Flamewheel has a DJI Naza flight controller, and I'm grateful that automatic landing at present position when voltage goes below a selected value is an optional feature you can program or not!

Yeah, well, I'm not sure if it has to do with where the engineers live.  I suspect the chemistry of the battery decides what it regards as cold and warm.  I personally like to make sure my DJI battery is somewhere close to 30C before I fly in cold weather.  

LOL  I love it!  But, is that a self cleaning oven?

fans76a55fe2 Posted at 2018-2-5 14:53
Well, my battery powered car calculates and displays remaining range continuously, and does indeed take temperature into account. In the summer (around 20 deg C), it says about 220-230 km when I start out with a fully charged battery, while yesterday, when it was minus 10, it showed about 170 km. The DJI software is very sophisticated, - it even calculates "bingo fuel" - heading home automatically when battery capacity and distance out dictates a return. But initiating a landing when the battery is at 80% and it's just a few hundreds meters away? That appears more like a software bug to me...  I really can't see that it should be any problem to include temperatures in the calculations?

According to your description, the landing is triggered due to the critical battery voltage/low temperature, instead of battery level. Warming up to the working temperature is essential in cold weather. You may need battery heater in this kind of situation: https://store.dji.com/product/ph ... om=search-result-v2

A knee gel pack in the microwave for 2 minutes. Drop it in the P3P case on the batteries and they warm up nicely.
My oldest battery, 250 charges, misbehaves when cold, but is fine when warmed up. The wear of the batteries is the differentiating factor.
But soon we all will be Mavic Airing......

Are you comparing your electric car with your drone? You probably don't know nothing about batteries type lipo! Thanks DJI for saving your drone

I find this all interesting.

OP is flying with battery at +13C .......... and I have to agree with his frustration. +13C is NOT a low figure for a LiPo in fact.

If I am in a spring day of +10C or over - I NEVER pre-warm my batterys ... I use as is. NEVER any problem at all. I only prewarm when temps are below +10C.
People can quote DJI info as much as they want - but DJI specs say operating temp is 0 - 40C .............. yes well if we kept to that a lof of excellent flights and videos would never happen. It shows that DJI are playing safe and NOT actually quoting fact.

That goes for ALL my LiPo's .... DJI and general RC.

Nigel

Vendex Posted at 2018-2-6 01:37
Are you comparing your electric car with your drone? You probably don't know nothing about batteries type lipo! Thanks DJI for saving your drone

I know the difference between a Lithium Ion- and a Lithium Polymer battery, thank you. I'm afraid you have missed my point - DJI isn't saving my drone in any way by suddenly ditching it in the fjord (which is not ice covered in the summer...), when it is actually able to fly! In most situations it is best to get the aircraft back to the "airfield" - the home point - if at all able to maintain flight, and to make a controlled landing here, instead of having no control of over where it is going down. Could create some pretty unsafe situations on the ground as well.

ALABAMA Posted at 2018-2-5 18:12
LOL  I love it!  But, is that a self cleaning oven?

it is.  Thanks for asking.  

if it's cold out, like close to freezing, I'll warm my battery.  If it's not so cold, I'll still give it a little bump, not because I think the battery will shut off, but because I know the battery will perform a little more efficiently if it's over 20C.

fans76a55fe2 Posted at 2018-2-6 02:10
I know the difference between a Lithium Ion- and a Lithium Polymer battery, thank you. I'm afraid you have missed my point - DJI isn't saving my drone in any way by suddenly ditching it in the fjord (which is not ice covered in the summer...), when it is actually able to fly! In most situations it is best to get the aircraft back to the "airfield" - the home point - if at all able to maintain flight, and to make a controlled landing here, instead of having no control of over where it is going down. Could create some pretty unsafe situations on the ground as well.

LiIon and LiPo are actually based on same electrolytes ... its the construction strata that is different.

That is why people get confused when they read such as Battery University who talk about LiIon etc. when advising on LiPo ...

The Po only means Polymer ... in fact a LiPo is an abbreviated form of :

LiIon-Polymer battery.

Nigel

You stated it "refused to start" and "refused to take off" in the initial post.  That isn't the same thing.  Although it appears to be high, they picked 15° as a cutoff point.  As stated above, cold batteries can be damaged and/or fail to deliver high currents when cold.  There have been a few reports of batteries shutting down in the cold, and subsequent firmwares have included cutoff temperatures and shutdown.  It is likely that the battery temperature, which is monitored on the skin of the battery, was too low.   It did not permit flight due to safety reasons.  It would permit startup. which would quickly bring the temperature up to operating limits with a short idling period.   Keep in mind the decision to implement these things is to deal with the lowest common denominator (i.e. least experienced operator or outright stupid and irresponsible).  Handling a frozen battery in arctic conditions could artificially raise the skin of the battery to "normal" temperature, while the core is incapable of proper operation.  It is likely that for these reasons, the cutoff temperature appears to be quite high.  Once again, it is nothing that idling the motors for a few seconds won't address.

Regarding it indicating a critical battery at 80% and wanting to land, we have seen similar behaviour when the battery was not fully charged immediately before flight, or was previously fully charged and left to sit for days.  This causes the battery to self-discharge and the reported calculated battery capacity is incorrect.  It is possible it was particularly cold and was being flown hard as well, leading to the aircraft going into self-protection mode from this "lowest common denominator" protection.  It is designed to land immediately while it still has reliable power reserves, rather than just drop out of the sky dangerously.  It has no idea if it is landing on ice or water or in a volcano or on top of people.  That is the responsibility of the pilot to avoid such things.  Your observation of the warning message is a bit imprecise, so we can't know for sure what was going on (short of examining your flight log and internal flight recorder).   The sort of response and your subsequent action will have a great deal to do with the exact fault flashed up at you.   Personally I'd be more concerned about an immediate cold battery shutdown than a critical battery alert, and my reactions would be quite different.   

If you find yourself over a hazard in this situation, you do still have some control as it is descending -- you can move laterally and to some extent you can push up and avoid it descending immediately, effectively cancelling out its down command with your up command.  This will enable you to fly a little further still, but don't expect it to get you out of trouble if you are 2 km out over the sea.   You can delay landing but eventually the battery will become so low that it will insist on landing and ignore any up commands.  In the situation where the battery charge level is unreliable, it is not recommended to push your luck and to just land immediately wherever you are.  The battery level is completely untrustworthy, even for the flight systems.

Hopefully you can see that they aren't doing these things for the sole purpose of annoying you, there is a reason behind the decision.  Of course you may decide the parameters are too conservative for you if you like flying on the edge of the envelope, and that may be the case.  However as a company they are providing a product to everyone, not just you, and they have to be mindful of the unskilled and reckless fliers using their products along with the skilled, responsible ones.  Therefore the parameters need to be conservative.

endotherm Posted at 2018-2-6 05:05
You stated it "refused to start" and "refused to take off" in the initial post.  That isn't the same thing.  Although it appears to be high, they picked 15° as a cutoff point.  As stated above, cold batteries can be damaged and/or fail to deliver high currents when cold.  There have been a few reports of batteries shutting down in the cold, and subsequent firmwares have included cutoff temperatures and shutdown.  It is likely that the battery temperature, which is monitored on the skin of the battery, was too low.   It did not permit flight due to safety reasons.  It would permit startup. which would quickly bring the temperature up to operating limits with a short idling period.   Keep in mind the decision to implement these things is to deal with the lowest common denominator (i.e. least experienced operator or outright stupid and irresponsible).  Handling a frozen battery in arctic conditions could artificially raise the skin of the battery to "normal" temperature, while the core is incapable of proper operation.  It is likely that for these reasons, the cutoff temperature appears to be quite high.  Once again, it is nothing that idling the motors for a few seconds won't address.

Regarding it indicating a critical battery at 80% and wanting to land, we have seen similar behaviour when the battery was not fully charged immediately before flight, or was previously fully charged and left to sit for days.  This causes the battery to self-discharge and the reported calculated battery capacity is incorrect.  It is possible it was particularly cold and was being flown hard as well, leading to the aircraft going into self-protection mode from this "lowest common denominator" protection.  It is designed to land immediately while it still has reliable power reserves, rather than just drop out of the sky dangerously.  It has no idea if it is landing on ice or water or in a volcano or on top of people.  That is the responsibility of the pilot to avoid such things.  Your observation of the warning message is a bit imprecise, so we can't know for sure what was going on (short of examining your flight log and internal flight recorder).   The sort of response and your subsequent action will have a great deal to do with the exact fault flashed up at you.   Personally I'd be more concerned about an immediate cold battery shutdown than a critical battery alert, and my reactions would be quite different.   

Thanks for a thorough answer.

- "Refused" meant that nothing happended whatsoever when I executed CSC to start the motors, except a message in DJI Go that battery temp was too low (Guess I was a bit unclear there.)

- About the flight where it wanted to land: The battery was fully charged, but indicated 95% prior to takeoff - probably because of low temperature. I flew straight away from me in a climb, and I realise I was probably a bit hard on the throttle and stick so early in the flight. Having just had a quick look at the flight data at Airdata.com, which I sync my flights with, there is one point during this climb where the log says "Warning:Motor Overloaded. Aircraft will decelerate to ensure safety." I can't remember seeing this in the app though. But I see in the log that there is a voltage drop, and I guess that's why it suddenly wanted to land - without any prior warnings as far as I could observe. (Didn't get the "Propulsion output is limited to ensure the health of the battery" warning either, which sometimes happen when you combine full horizontal speed with max climb.) Luckily, the system gives you some control of the aircraft, so I managed to stop the self initiated descent by applying a considerable amount of throttle, and fly back to the home point.

One thing I learned from the video posted earlier in this thread, was that voltage drops, which is normal when you suddenly draw a lot of power from a battery, can be more severe when the battery is cold, so I can see I have to be more careful until the battery has warmed up! But other than that, a Lithium battery, whether it's LiIon or LiPo functions well at considerably lower temperatures than what DJI has decided. (I speak from experience with my Flamewheel F550, where I have disabled any automatic actions triggered by battery voltage in the Naza controller.)

If could give DJI a wish list over adjustments in their firmware / software it would be:

1. Set the minimum temp. for startup lower than 15 C, for example 10.
2. But at the same time, let the automatic throttle back function kick in earlier - as soon as it observes voltage drop rates becoming threatening. And since battery temperature is one of the parameters fed into the controller, it could adjust the function in relation to that. Also, I'm not sure, but it seems that this function only decelerates the aircraft, without reducing the climb - it should do both.

DJI Susan Posted at 2018-2-5 18:52
You may need battery heater in this kind of situation: https://store.dji.com/product/phantom-3-battery-heater?from=search-result-v2

Thanks for the tip - that might be useful outdoors when you have no other means to heat the battery!

You should be able to fly it without any problem. DJI own specs guarantee operation until -10ºC, though it is true under 0ºC batteries become very temperature dependent and their output is affected. I flown many times my P3A under -15ºC without any problem, except for a triggering pop-up indicating due to low temperature, the power of the engines will be reduced. But the drone still flies and no landing or RTH required or triggered. The same for my P4P+ flying at -25ºC without any other previous preparation than 2-3 minutes warm-up before take-off. I'm affraid there is something else with your battery, but at +13ºC no need for battery heaters nor other stuff.

fans43eed3c2 Posted at 2018-2-7 07:22
Thanks for the tip - that might be useful outdoors when you have no other means to heat the battery!

Far better solution than the DJI unit ...

https://hobbyking.com/en_us/turn ... v-dc.html?wrh_pdp=3

Any 12v source powers it and you can set temperature as you want ... easily takes 2 P3 batterys.



I use old 3S LiPo's that are no longer any use for flying other models. In the car - it plugs into ciggy socket.

Nigel

solentlife Posted at 2018-2-7 09:03
Far better solution than the DJI unit ...

https://hobbyking.com/en_us/turnigy-programmable-lipo-battery-warmer-bag-12v-dc.html?wrh_pdp=3

Smart solution! :-)  I have some old LiPo's myself, which I don't dare fly with any longer - I think I have to order this one!

Would an electric hand warmer work. Was thinking of putting that and my batteries in a polystyrene box.

Low temperature discharge on Phantom

It keeps saying Low temperature discharge and a let it warm up and still hasn’t done anything I don’t know what is wrong with it

djiuser_IX9ekEmJ3SXb Posted at 2-17 12:58
Low temperature discharge on Phantom

It keeps saying Low temperature discharge and a let it warm up and still hasn’t done anything I don’t know what is wrong with it

Hi there. We do apologize for the trouble. Can you please confirm what specific DJI Phantom series are you using? Please provide us a screenshot of the error message for reference. We will wait for your response.

My instinct would be to heat it up before you insert it into your Phantom.   Put it in an inner pocket of your winter coat for a while.