Greetings all,

I pulled out my Mavic Mini 3 Pro a few days ago to fly for the first time in three months only to be very disappointed that the batteries were 100% drained. I have the Fly More kit, so the 3 batteries were stored in their charger. The controller still had full power.

Why did that happen?

Then I found this thread, which I found confusing...https://forum.dji.com/thread-275687-1-1.html#:~:text=The%20DJI%20Mini%203%20Pro's%20Intelligent%20Flight%20Battery%20automatically%20discharges,battery%20while%20it%20is%20discharging.

>The DJI Mini 3 Pro's Intelligent Flight Battery automatically discharges to approximately 96% of the battery level when it is idle for one
>day, and approximately 60% when idle for nine days.

Why would the batteries discharge in one day? That makes absolutely no sense because not only is that extremely inconvenient, that kind of behavior contradicts best practice for LiPo batteries... that is, they should never be allowed to drain to 0%.

I must be misunderstanding that statement.

When I owned the DJI Mavic Mini, I never had a problem storing its fully charged batteries in its charger bay for months. Every time I wanted to use that drone, there was only an expected small percentage of battery loss.

Can anyone explain this behavior?

I am not going to be happy if I must plan ahead because it takes about 24 hours to fully charge all three batteries.

Thank you.
Shawn

Thanks

Because when LIPO are fully charged at 100%, if not used, they can inflate. All LIPO manufacturer do recommend not to store the LIPO at 100% capacity for that reason..
In one day the DJI battery goes down to 96%, so yes you are misunderstanding their statement.. I just checked my Mini3P and after no use for 3 weeks, they are all three down to 2 LED...

On my Mavic, I check the battery weekly to see what their level of charge is... If they are low, I charge them to 3 LED if I'm not planning any flight the day after...

Burt37 Posted at 6-19 19:40
Because when LIPO are fully charged at 100%, if not used, they can inflate. All LIPO manufacturer do recommend not to store the LIPO at 100% capacity for that reason..
In one day the DJI battery goes down to 96%, so yes you are misunderstanding their statement.. I just checked my Mini3P and after no use for 3 weeks, they are all three down to 2 LED...

Thanks, that's fair. I now see what I did in my misinterpretation! :O Stupid me, I misread that quote to mean that the batteries are discharged with 4% remaining power after one day! LOL

I understand that LiPo's should not be kept at 100% nor allowed to fall to 0%.

Maybe I'm unique? It's normal for me to not use my drone for months (I live in the middle of a big city). But I swear, I have never experienced 100% battery drainage in just 3 months on any of my previous drones.

Now that I am aware of the potential issue, I will check the batteries weekly and plot a discharge curve. Two batteries remain in the charging caddy, and one is pulled out.

What I expect to see is that after 9 days, where the battery have been discharged to about 60% or optimal charge level, the discharge rate should settle in at a normal LiPo discharge rate 2% per month.

If my batteries are fully discharged within 3 months, I think that is a problem.

Thanks again for your reply.

sdcinvan Posted at 6-19 22:53
Thanks, that's fair. I now see what I did in my misinterpretation! :O Stupid me, I misread that quote to mean that the batteries are discharged with 4% remaining power after one day! LOL

I understand that LiPo's should not be kept at 100% nor allowed to fall to 0%.

I agree. If your battery are fully discharged (as in 0 Volts) after 3 month you will have dead batteries. But the thing is, when you say fully discharge, do you mean that you have no LED's coming on or that you have tested the battery and it shows o volts? Just because the charger doesn't show any LED it doesn't mean that the battery is fully discharged. It just mean it need charging... I don't think your batteries are actually dead. I think you just need to charge them

Try to charge them and see how it goes...

Burt37 Posted at 6-19 23:59
I agree. If your battery are fully discharged (as in 0 Volts) after 3 month you will have dead batteries. But the thing is, when you say fully discharge, do you mean that you have no LED's coming on or that you have tested the battery and it shows o volts? Just because the charger doesn't show any LED it doesn't mean that the battery is fully discharged. It just mean it need charging... I don't think your batteries are actually dead. I think you just need to charge them

Try to charge them and see how it goes...

When I said 0% charge, I mean completely dead... all three batteries had no charge remaining.

I am 80% certain that they were at 100% about 3 months ago.

I didn't test them on a meter (perhaps I should have), but I did try to power up the drone with each of them and nothing happened, as expected with 0 charge batteries.

But they are fully charged now, which took about 24 hours with the caddy.

sdcinvan Posted at 6-20 00:06
When I said 0% charge, I mean completely dead... all three batteries had no charge remaining.

I am 80% certain that they were at 100% about 3 months ago.

If they were down to 0 Volts, there is no way that you would have been able to recharge them... Below 3.2 volts a Lipo is dead. Just because the drone didn't start it doesn't mean they were dead... The drone and the battery do have failsafe voltage built in to make sure that you will never go below the 3.2v mark.. Actually they probably stop working at 3.5 or 3.6 volts, to make sure the battery is ok...

Another thing to keep in mind is that when the battery are on the caddy (3 battery charger) they will all go down to the lowest battery... So if you have one fully charged and two flat the day after or few days after, you may find that you have 1 LED for each of the batteries... They balance themselves out...

Burt37 Posted at 6-19 19:40
Because when LIPO are fully charged at 100%, if not used, they can inflate. All LIPO manufacturer do recommend not to store the LIPO at 100% capacity for that reason..
In one day the DJI battery goes down to 96%, so yes you are misunderstanding their statement.. I just checked my Mini3P and after no use for 3 weeks, they are all three down to 2 LED...

Yes, that is the same experience I have had, leave them a couple of weeks and it takes a good couple of hours to recharge back.

I must admit it can be a bit disconcerting the first time you experience it, i.e. not flying for a week and then flying with what you thought were fully charged batteries, only to find them down to below 70%.

I think it is in the manual somewhere, but the batteries start draining after a few hours of non-use to protect them.  It is not good for the battery to be fully charged or fully drained for long periods.  I think the charger is supposed to stop at about 50% charge.  If your batteries go down to 0%, you might have an issue with the charger.  I've never had mine go down to zero, and I had left them for a few months of non-use during the winter (I do have the fly-more kit).

Hi, Shawn. Thank you for reaching out. The auto-discharging function has been applied with the Mini 3 Pro battery to prevent swelling. The battery automatically goes down to approximately 96% if it is not been used for one day, from 100% to 96%. For long-term storage of batteries please check the information below:
During storage, the battery will deplete at an extremely low speed as is normal for lithium batteries. When the battery level is extremely low, batteries may over-discharge. To maintain battery activity and extend battery use life, it is recommended to discharge the battery to 40% - 65% when it will not be used for 10 days or longer and store it in a dry and cool place (22°C - 28 °C). Check the battery level every three months and then let the battery completely discharge and then recharge it. Pay attention to battery maintenance during daily use.

Burt37 Posted at 6-20 00:14
If they were down to 0 Volts, there is no way that you would have been able to recharge them... Below 3.2 volts a Lipo is dead. Just because the drone didn't start it doesn't mean they were dead... The drone and the battery do have failsafe voltage built in to make sure that you will never go below the 3.2v mark.. Actually they probably stop working at 3.5 or 3.6 volts, to make sure the battery is ok...

Another thing to keep in mind is that when the battery are on the caddy (3 battery charger) they will all go down to the lowest battery... So if you have one fully charged and two flat the day after or few days after, you may find that you have 1 LED for each of the batteries... They balance themselves out...

Fair enough. I didn't check for a detectable voltage via a meter... only that they showed no sign of life when connected to the drone.

DJI Gamora Posted at 6-20 04:32
Hi, Shawn. Thank you for reaching out. The auto-discharging function has been applied with the Mini 3 Pro battery to prevent swelling. The battery automatically goes down to approximately 96% if it is not been used for one day, from 100% to 96%. For long-term storage of batteries please check the information below:
During storage, the battery will deplete at an extremely low speed as is normal for lithium batteries. When the battery level is extremely low, batteries may over-discharge. To maintain battery activity and extend battery use life, it is recommended to discharge the battery to 40% - 65% when it will not be used for 10 days or longer and store it in a dry and cool place (22°C - 28 °C). Check the battery level every three months and then let the battery completely discharge and then recharge it. Pay attention to battery maintenance during daily use.

Thank you.

I have added a schedule to remind me to recharge the batteries every three months.

The original intent of my post was to determine why the batteries seemed completely drained after 3 months. But it's possible that I am in error. This time, I will watch them more carefully to determine if there is an issue with excessive battery drain or if this observation was entirely my error.

Burt37 Posted at 6-20 00:14
If they were down to 0 Volts, there is no way that you would have been able to recharge them... Below 3.2 volts a Lipo is dead. Just because the drone didn't start it doesn't mean they were dead... The drone and the battery do have failsafe voltage built in to make sure that you will never go below the 3.2v mark.. Actually they probably stop working at 3.5 or 3.6 volts, to make sure the battery is ok...

Another thing to keep in mind is that when the battery are on the caddy (3 battery charger) they will all go down to the lowest battery... So if you have one fully charged and two flat the day after or few days after, you may find that you have 1 LED for each of the batteries... They balance themselves out...

>Another thing to keep in mind is that when the battery are on the caddy (3 battery charger) they
>will all go down to the lowest battery... So if you have one fully charged and two flat the day after or
>few days after, you may find that you have 1 LED for each of the batteries... They balance themselves
>out...

And there it is! That might explain what I experienced.

Thank you.

Do these batteries have a hibernate mode? perhaps they were not completely dead but had gone into hibernation and required x amount of time on charge to wake them up?

3 months is a long time to leave them in my opinion, during my downtime, i try to check them every couple of weeks, in doing so resets them to the beginning of the 9 days.

Bashy Posted at 6-20 18:12
Do these batteries have a hibernate mode? perhaps they were not completely dead but had gone into hibernation and required x amount of time on charge to wake them up?

3 months is a long time to leave them in my opinion, during my downtime, i try to check them every couple of weeks, in doing so resets them to the beginning of the 9 days.

Yes they do...

From the manual:

"Hibernation Mode: If the battery cell voltage is lower than 3.0 V or the battery level is less than 10%,
the battery enters Hibernation mode to prevent over-discharge. Charge the battery to wake it from
hibernation."

Your battery isn't dead. There still at least 3v and up per cell. If your battery been drain to 0%, it would never charge back. Just cause you press the power button and it doesn't show any light doesn't mean its 0%. There still voltage but just not enough to show on the led lights.

sdcinvan Posted at 6-20 07:30
Thank you.

I have added a schedule to remind me to recharge the batteries every three months.

No worries, Shawn. Should you need further assistance, don't hesitate to reach us back here at DJI Forum. Have a good one!

sdcinvan Posted at 2023-6-20 07:30
Thank you.

I have added a schedule to remind me to recharge the batteries every three months.

Hi, I have just had the same experience, haven’t used the drone for a few months.

2 batteries in the charger, no leds. However my third battery was in the Mini 3 Pro and has 2 leds.

I’m sure the batteries in the charger were previously full. I thought I noticed over cooking of the discharge before, when stored this way. I’ll do a proper check next time, but it may be storing in the charger risks dropping to zero percent ( not zero volts) which isn’t ideal.

djiuser_lpAQIMbXRZPv Posted at 4-8 08:07
Hi, I have just had the same experience, haven’t used the drone for a few months.

2 batteries in the charger, no leds. However my third battery was in the Mini 3 Pro and has 2 leds.

I'm really glad I found this topic, I had the same happen to me and was wondering if there's something wrong with my batteries.

DJI Gamora Posted at 2023-6-20 04:32
Hi, Shawn. Thank you for reaching out. The auto-discharging function has been applied with the Mini 3 Pro battery to prevent swelling. The battery automatically goes down to approximately 96% if it is not been used for one day, from 100% to 96%. For long-term storage of batteries please check the information below:
During storage, the battery will deplete at an extremely low speed as is normal for lithium batteries. When the battery level is extremely low, batteries may over-discharge. To maintain battery activity and extend battery use life, it is recommended to discharge the battery to 40% - 65% when it will not be used for 10 days or longer and store it in a dry and cool place (22°C - 28 °C). Check the battery level every three months and then let the battery completely discharge and then recharge it. Pay attention to battery maintenance during daily use.

I had the same problem as Shawn. During 2 months 3 batteries on the 3-battery charger went down to 1% and the battery on the mini 3 pro maintained 30% charge. how do you explain this?

This makes me think that the 3-battery sequential charger over-discharges the batteries and they shouldn't be fully inserted when stored for a long time.

I have a ritual of recharging all of my various DJI drone flight & RCs every 30-60 days.  I have never allowed them to go "months" between recharges as I know the ramifications of that degree of negligence.  Once the batteries have discharged to the storage charge (60-65%), the auto-discharge is done, but the batteries do continue to slowly discharge as the BMS (battery management system) is always drawing a small amount of power & draining the batteries.

The amount of discharge will increase as the batteries age.  My Phantom 2 & Phantom 3 batteries are quite old (8-10 years).  Some will be drained to only a single bar after a couple of months.  One of my P3 batteries actually took a dump.  It will power on but won't charge at all.  

My recommendation is charge them to at least 65% charge once a month.  Don't let them set for 2+ months or you risk losing them completely.

djiuser_lpAQIMbXRZPv Posted at 4-8 08:07
Hi, I have just had the same experience, haven’t used the drone for a few months.

2 batteries in the charger, no leds. However my third battery was in the Mini 3 Pro and has 2 leds.

Hi there. You can check the DJI Support page to see the Battery Routine Maintenance Guide. Here is the link: https://support.dji.com/help/con ... p;re=US&lang=en. Have a nice day.

caixadoricardo Posted at 4-28 10:28
I had the same problem as Shawn. During 2 months 3 batteries on the 3-battery charger went down to 1% and the battery on the mini 3 pro maintained 30% charge. how do you explain this?

This makes me think that the 3-battery sequential charger over-discharges the batteries and they shouldn't be fully inserted when stored for a long time.

I’ve confirmed my suspicions, by leaving fully charged batteries in the charger, then recharging and storing them singly. The multi charger definitely discharges them faster and deeper.

I’ll be keeping a better eye on my batteries from now on, but not stored in the multi charger. I’m spoiled by my old Mavic Pro batteries, they can hold at 50% for months even after all these years since new.

caixadoricardo Posted at 4-28 10:28
I had the same problem as Shawn. During 2 months 3 batteries on the 3-battery charger went down to 1% and the battery on the mini 3 pro maintained 30% charge. how do you explain this?

This makes me think that the 3-battery sequential charger over-discharges the batteries and they shouldn't be fully inserted when stored for a long time.

Hi, caixadoricardo. We currently don't have information as to why it happened but we suggest to try to fully charge the batteries and then store them again (without any interference during storage). If after two months, it's still the same situation, then send the 1% battery back for inspection.