Thoughts on multiple take offs with same battery/same day...

[Ron-EP]

Hey all,

I know DJI states to only fly with a fully charged battery. I always wonder though is it really that bad to use the same battery for multiple jobs on the same day? Obviously on job #1 for example(in this case my Mavic 3) i can use only 20% of my battery, then on the next job maybe another 20 or 30%..and so on. Does anyone do this? is it a bad practice? Seems wasteful on my battery to not fully use them within the same day...and i dont mean btw taking off with 20% batttery. Im just speaking about when its still in an acceptably high percentage.

thoughts?

Thanks!

 

[Yorkshire_Pud]

I do multiple flights on one battery all the time (not M3) but the charge would be relatively fresh and the drone tends to be 'close'. If I am planning to fly 'distance' that would be a different matter.

 

[akdrone]

I'll be curious to hear any definitive answers. I don't think DJI is making that recommendation because the battery would be damaged. I take it as a recommendation to ensure you have enough battery to get home and not have any battery related problem. I do not think (not a chem engineer...) that depleting a battery from 80 to 60% is a problem for the battery itself and can't imagine any other issue.

 

[old man mavic]

@Ron-EP taking off with a less than fully charged battery ,really means that ones options for a safe and successful flight ,are reduced by the way that the battery cells ability to discharge are reduced as the charge level is used up
sure you could fly in this way ,there is nothing stopping you,but is it worth the risk to your equipment, or the consequence's ,of any damage or injury ,that may ensue if something went wrong

 

[DronePhotosNZ]

Hey all,

I know DJI states to only fly with a fully charged battery. I always wonder though is it really that bad to use the same battery for multiple jobs on the same day? Obviously on job #1 for example(in this case my Mavic 3) i can use only 20% of my battery, then on the next job maybe another 20 or 30%..and so on. Does anyone do this? is it a bad practice? Seems wasteful on my battery to not fully use them within the same day...and i dont mean btw taking off with 20% batttery. Im just speaking about when its still in an acceptably high percentage.

thoughts?

Thanks!

I regularly use 'part' batteries, but only in situations where you can get back

I've had a couple of 'moments' when it got a bit touch and go relative to if the drone was going to get back or not when over water etc

You'll soon learn to read the battery levels to suit your flying

Horses for courses as it were, when in critical situations, always fly fully charged, when not so critical ( vertical above you to shoot a sphere pano for example ) then you can fly with a fairly depleted battery

I'm using primarily a MA2s but it's amazing how long the machine will actually keep flying for in an emergency

I don't recommend using really low batt levels as this will shorten battery life rapidly, but 30% is fine for short trips

Just my opinion

Cheers, Stu

 

[JimSteadman]

Like most questions, the answer is "it depends." I do it all the time. I use my drone to get a camera into a position to take a photo or series of photos of a particular subject. I very seldom take videos. So if you know what you want to photograph, and you take the photos and the drone has been up for only a few minutes, you still have plenty of juice to fly again.

If you use your drone to take videos where you will be leaving most of the 'film' on the cutting room floor, you want to constantly watch your remaining battery to make sure you are not going to run out of battery life when you are swooping around filming.

My concern has always been putting a battery which already has 25 - 30% battery life left into the charger so that it is fully charged when I fly. I have not experienced any problem with fully charging a partially charged battery. If there are issues with that, I'd be interested to hear about them.

 

[DronePhotosNZ]

Like most questions, the answer is "it depends." I do it all the time. I use my drone to get a camera into a position to take a photo or series of photos of a particular subject. I very seldom take videos. So if you know what you want to photograph, and you take the photos and the drone has been up for only a few minutes, you still have plenty of juice to fly again.

If you use your drone to take videos where you will be leaving most of the 'film' on the cutting room floor, you want to constantly watch your remaining battery to make sure you are not going to run out of battery life when you are swooping around filming.

My concern has always been putting a battery which already has 25 - 30% battery life left into the charger so that it is fully charged when I fly. I have not experienced any problem with fully charging a partially charged battery. If there are issues with that, I'd be interested to hear about them.

I've never had issues charging a battery with at least some charge, but once sadly had the situation of a battery becoming 'bricked' due to FULLY depleting it ( negative minutes flying time left )

Having to throw a battery away gets you out of that habit REAL quick

 

[chiangmaicharlies]

All seem sensible replies. I read recently that drone batteries should be depleted to zero 'regularly.' Any experience or thoughts on this? I'm generally flying in a small area (no great distance away) and use batteries until DJI warn me they're low. I then change them, and recharge from that position, not fully depleting them ever, as yet.

 

[wardtom084]

With a partly used battery. For example I like to be up with the air ambulance is coming into town. I will go up a few munities before they are scheduled to be in town. I may fly around a little, they come in and I have 60 percent of battery left. I will usually take it up again later in the day just flying around very locally using up the rest of the battery. I have about 60 flights on 3 batteries that way and may have 16 percent left for storage until ready to charge up and head out again.

 

[izometric]

The drone will fly with a partly charged battery, that's not a problem.

If you are careful enough with the distance and wind, you can absolutely do it. Bear in mind that at some point below a certain voltage, the drone will reduce power and will commence auto-land process, you will have to fly at much less available power with the left stick up to come back.

 

[chiangmaicharlies]

With a partly used battery. For example I like to be up with the air ambulance is coming into town. I will go up a few munities before they are scheduled to be in town. I may fly around a little, they come in and I have 60 percent of battery left. I will usually take it up again later in the day just flying around very locally using up the rest of the battery. I have about 60 flights on 3 batteries that way and may have 16 percent left for storage until ready to charge up and head out again.

What about the suggestion that batteries should regularly be COMPLETELY depleted?

 

[vindibona1]

You must allow the batteries to cool before recharging, lest you greatly shorten their life expectancy.

 

[izometric]

Don't worry, you cannot charge a hot DJI battery even if you try.

 

[EsaT]

If needed range and flight time are long, there's significant wind and lack of places suitable for plan B/emergency landing (especially longer flights above water) high/fully charged battery is always the wisest course of action.
And especially if battery has already seen aging/wear, or you've let it cool to freezing temperatures full charge is important.
At the least those warrant extra care in monitoring individual cell voltages.
(unfortunately not made easy by DJI dungFly)

But if needed range and conditions allow it, there's no need for fully or even highly charged battery.
In fact charging drone batteries always 100% full when that's not necessary is very harmfull for batteries.


While "good ol" lead acid batteries in cars etc. are happiest when as close to 100% charge as possible, for lithium chemisty that's as happy condition as the best ever sauna I've been in would be to most of you (how does 110C/230F sound?) and lithium based batteries are at their happiest at mid level charges.

Every time when lithium cell voltage exceeds certain level, it starts capacity degrading reaction and obviously the highest voltage causes the fastest reaction.
(for super extra damage leave fully charged battery into sunlight in hot place like car)

Difference it makes is such high that charging to just 80% instead of 100% roughly doubles the available cycles per capacity loss from wear.
(cycle = charging/discharging nominal capacity worth of Ahs)
I have followed that practise with my 2018 bought Galaxy S8 and charged battery significantly above 80% only when really needing that.
And according to monitoring softwares estimated battery capacity is still 96% and certainly haven't gotten feeling of battery capacity going AWOL.


But on other end of scale I always aim to have over 30% of capacity left when touching down.
And also consider 40% battery empty for anything except maybe minute or two flight at very short distance in favorable conditions.
Besides flight safety getting best life time from battery needs avoiding low charges/deep discharges:
When cell voltage goes below certain level another chemical reaction starts eating capacity.

 

[Robert Prior]

I did that in Iceland when I had three batteries to last three days of flying. I figured I could get about three flights out of a battery, but I was basically going nearly straight up, shooting some panoramas, and landing again, not capturing cinematic video footage, so when I got the low battery warning I could just descend.

When I have the choice I prefer to launch with a full battery, and try to land before it gets to 30%, which I figure gives me a pretty good cushion. Depends a bit on temperature — on colder days the predicted flight time tends to be an overestimate (at least on the Mavic 2) so I won't cut so close.

 

[Barbara]

I think the question has been answered, but I will add my two cents.

Technically, there is no issue with flying a partially depleted battery. You can't run it down to a dangerous level (for the battery).

Safety wise, as per DJI's statement, a full battery is always going to give you the most leeway. I've flown many times on a less than fully charged battery. If I know that I only need a few minutes for the shot I want, no problem. I do have a bottom limit for battery level. Anything less than 30-35% is a no go.

Experience is your best guide. Air temperature, wind, battery age all need to be taken into consideration and always err on the side of caution.

 

[MAvic_South_Oz]

Agree in general, same day fine.
I consider DJI warning to only fly on a full battery is more to do with freshly charged, and not flying after auto discharge has started, or if not flying lower % same day.
Times that can allow for battery cells to become unbalanced.

Yes, of course consider use carefully.

Eg. If I had flown a battery to 30-40% making a flight and video clip, and changed to a new battery for a follow up flight further for safety, I would certainly take the drone up same day on the first battery if I needed to. . . but only for a simple short close clip, or straight up and down/ close by photo session.

If I had more fully charged batteries available, I wouldn’t bother and just leave that first battery at more or less discharged state.

 

[JimSteadman]

All seem sensible replies. I read recently that drone batteries should be depleted to zero 'regularly.' Any experience or thoughts on this? I'm generally flying in a small area (no great distance away) and use batteries until DJI warn me they're low. I then change them, and recharge from that position, not fully depleting them ever, as yet.

I have never depleted a battery to zero and always fully charge them. Never had a problem in 2+ years as a result. Not sure how you deplete them to zero anyway without having the drone fall from the sky. Like you, when I get the warning I get the drone on the ground and put in a fresh battery.