Is taking-off with a 95% battery (let's say a few days after charging) safe enough or should we rech

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Would it be safe to fly after a fully charged battery has sat idle for a few days wherein the battery level has gone down to 95%? What actually is the minimum battery level for taking off?
 

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Would it be safe to fly after a fully charged battery has sat idle for a few days wherein the battery level has gone down to 95%? What actually is the minimum battery level for taking off?
There's no easy answer.
It probably will be but there is a point where using a partly discharged battery isn't safe.
It's easy enough to top it up and fly with a full battery.
You might have to switch the battery on the get it going if it's above 90%.
 
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Having the most amount of battery supply will always be the best option. You will be cheating yourself more then anything if taking off without a full charge.
 
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I think it would be fine. It's safest to stick with best practices though. Charge your batteries the day before or the day when you plan to head out to fly.
 
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I think it would be fine. It's safest to stick with best practices though. Charge your batteries the day before or the day when you plan to head out to fly.

I would agree with you 100% but sometimes our intended day to fly doesn't always push through and I was concerned whether or not it would be unhealthy for the battery If we keep topping it up?
 

msinger

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Personally, I'd rather top of the battery too many times than potentially lose my Phantom.
 
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There's no easy answer.
there is a point where using a partly discharged battery isn't safe.
It's easy enough to top it up and fly with a full battery.

Can you elaborate on the safety issue?

Of course I wouldn't fly with only 20% remaining charge (lipo discharge rate starts getting pretty steep at this point) but 90- 95% is easily enough for a still reasonable amount of flight time.
 

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Can you elaborate on the safety issue?
Of course I wouldn't fly with only 20% remaining charge (lipo discharge rate starts getting pretty steep at this point) but 90- 95% is easily enough for a still reasonable amount of flight time.
If you have 50% showing for your car fuel tank, you have 50%.
The battery indication in the app is not the same.
The voltage is dropping throughout the flight cycle - the last 20% isn't the same as the first 20%.
There are plenty of cases where Phantoms have fallen from the sky when people have flown with batteries that have been sitting around and are partially discharged.
At 95% it's probably going to be OK but at some (unknown and variable depending on conditions) level it won't be OK.
It's safer and so much easier to do as DJI recommend and only fly with a fully charged battery.
 
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If you have 50% showing for your car fuel tank, you have 50%.
The battery indication in the app is not the same.

Fair enough. As I alluded to in my post I'm fully aware that lipos don't discharge linearly.

At 95% it's probably going to be OK but at some (unknown and variable depending on conditions) level it won't be OK.
It's safer and so much easier to do as DJI recommend and only fly with a fully charged battery.

Unfortunately sometimes I don't have that luxury when travelling and making a few short flights on the same battery. Common sense and prevailing conditions should tell you when to stop!
 

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Unfortunately sometimes I don't have that luxury when travelling and making a few short flights on the same battery. Common sense and prevailing conditions should tell you when to stop!
Making a few short flights is very different from flying with a battery that has been sitting for a few weeks and is showing 60%.
 
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It's usually safe IF you know your batteries well and keep an eye for voltage X percentage. Not a good idea for flights in windy conditions, or if you're pushing hard on the motors (accelerations, etc.) or attempting long range. Or if your batteries are aging or showing lots of cell voltage variation.

What I usually do in that situation (95% after a couple of days sitting after charge) is a shorter, close range flight taking easy on the "aerobatics". And I land with 40-50% or whenever voltage starts jumping or dropping too much too fast, just to be safe.

Can be a small mapping job, a short and easy filming session or something that does't put a heavy load on the battery. For anything else I top them off as close as possible to the flight at hand, as others pointed out.
 
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