I was watching a video and saw something about intelligent batteries discharging themselves after a certian amount of time. It happens on the M2P. Does this happen to MM batteries?

No, because the batteries for the Mini are Lithium Ion batteries, while the other models use Lithium Polymer batteries. LiOn batteries do not need to be discharged.

Its suggested the mini batteries be discharged if you aren't using them for 10 days or so. I think down to 40 - 60%. I'm sure dji will chime in.

Trevor OV MM Posted at 4-3 16:59
Its suggested the mini batteries be discharged if you aren't using them for 10 days or so. I think down to 40 - 60%. I'm sure dji will chime in.

Yeah, DJI write confusing crap all the time in their manuals. As I said, LiOn batteries do not need to be discharged. Look it up.

Geebax Posted at 4-3 17:39
Yeah, DJI write confusing crap all the time in their manuals. As I said, LiOn batteries do not need to be discharged. Look it up.

Plenty of articles saying that it's better to store Lithium-Ion at 40-60% charge (see example). Maybe they all quote the same incorrect source (won't be the first time), but what makes you say it's not true?

120ccpm Posted at 4-3 21:18
Plenty of articles saying that it's better to store Lithium-Ion at 40-60% charge (see example). Maybe they all quote the same incorrect source (won't be the first time), but what makes you say it's not true?

Because Lithium Ion batteries are selected for use in devices that have to maintain a good charge for standby use at any time, a classic case are flashlights, power tools etc. Applications where you need to be able to pick them up at any time and know they have a good charge in them. If it was critical to their reliability to discharge them when not in use, they would be totally useless for their intended application. LiOn batteries have a definite lifetime, but it is not greatly affected by whatever charge state you keep them in, the greatest limiting factor of LiOn life is simply age.


LiPo batteries are far less tolerant to these types of applications, which is why you don't see them used in common everyday devices.

The numbers on the article I referenced tell a rather different story, with Li-Ion batteries losing 20% capacity in 1 year if stored at 100% charge, vs. 4% loss if stored at 40% charge (at room temperature). That seems a rather significant difference.  With iOS 13, Apple recently introduced an optimized charging option, specifically designed to reduce the time your battery stays at 100% charge. You can read about it here. They clearly state that full charge reduces the battery lifespan.
I personally try to store the MM batteries at 50%, like I do with all my Lipos.

All batteries LOSE capacity over time  if left fully charged or discharged!!!!!!!!!!!!!  Lipo can be damaged in few days while liion takes some more time. If you love your drone and batteries you will store them at 50% ( 40-60% ) when not using in more than few days.

ask that guy saying that mm batteries do not need to be discharged after a year what is his max flight time

I using tons of 18650 and never discharge them. They're all ok. Some of my batteries with 18650 inside (like Sony NP-F) are more than 5-8 years old and still ok.  18650 is best choice for drone, shame that we can't just use 18650 instead of expensive DJI batteries. BTW, Tesla using 18650s too. I'm very tired of LiPo. I'm very tired to trash swollen batteries - from Phantom 2 to Spark... Thanks for 18650, we can even repack it with new banks if something goes wrong.

Hi, Mavic Mini battery doesn't support self-discharge, please manually discharge the battery to 40% ~ 65% if you are not to use it more than10 days. Please put it on the charging hub or power it on the drone to discharge the battery. Thank you.

Due to weather, unfavorable conditions, appointment, work, etc., I don't always know whether I will use the drone in the next 10 days. Someone started to tell something about 40-60% and 10 days and then everyone repeated it. Nobody has or was able to take a long-term test and then compare them. For example, leave 1 battery at 100% for 6 weeks, the second at 50% and the third at 20%. And then after 1 or 2 or 3 years see which battery flies for how long under the same conditions.

I once saw a YouTube video where someone tried to open the battery pack and replace the 18650 cells. In addition to mechanical damage, it was not possible to make the batteries ready for use. The "battery electronics" seems to become "deactivate" or maybe destroyed when changing. Or has someone tried it successfull ?

jonny007 Posted at 4-4 01:46
Due to weather, unfavorable conditions, appointment, work, etc., I don't always know whether I will use the drone in the next 10 days. Someone started to tell something about 40-60% and 10 days and then everyone repeated it. Nobody has or was able to take a long-term test and then compare them. For example, leave 1 battery at 100% for 6 weeks, the second at 50% and the third at 20%. And then after 1 or 2 or 3 years see which battery flies for how long under the same conditions.

I once saw a YouTube video where someone tried to open the battery pack and replace the 18650 cells. In addition to mechanical damage, it was not possible to make the batteries ready for use. The "battery electronics" seems to become "deactivate" or maybe destroyed when changing. Or has someone tried it successfull ?

The Batteries have DJI Circuits, because they get firmware updates

jonny007 Posted at 4-4 01:46
Due to weather, unfavorable conditions, appointment, work, etc., I don't always know whether I will use the drone in the next 10 days. Someone started to tell something about 40-60% and 10 days and then everyone repeated it. Nobody has or was able to take a long-term test and then compare them. For example, leave 1 battery at 100% for 6 weeks, the second at 50% and the third at 20%. And then after 1 or 2 or 3 years see which battery flies for how long under the same conditions.

I once saw a YouTube video where someone tried to open the battery pack and replace the 18650 cells. In addition to mechanical damage, it was not possible to make the batteries ready for use. The "battery electronics" seems to become "deactivate" or maybe destroyed when changing. Or has someone tried it successfull ?

Nobody has or was able to take a long-term test and then compare them

Li-ion is not new technology, many test have been presented, DJI suggestions only meet today's standards. It is not the capacity You are aware of, it is the voltage and discharge characteristics. If You store the battery half-charged and recharge fresh for the flight, the cell keeps the voltage better and longer and the cell is loosing capacity with number of charge cycles slower. That's all...

Pashi Posted at 4-4 00:00
I using tons of 18650 and never discharge them. They're all ok. Some of my batteries with 18650 inside (like Sony NP-F) are more than 5-8 years old and still ok.  18650 is best choice for drone, shame that we can't just use 18650 instead of expensive DJI batteries. BTW, Tesla using 18650s too. I'm very tired of LiPo. I'm very tired to trash swollen batteries - from Phantom 2 to Spark... Thanks for 18650, we can even repack it with new banks if something goes wrong.

This post is wrong on so many levels, I'm not even sure where to begin.
18650's are not as good at current discharge as LiPos, that why they arent used generally for drones.
When a cell fails in a drill, it doesnt fall out of the sky, unlike a drone. If a torch shines a little less brighter, most people are happy to wear that consequence for having it always available and ready to operate, drones becomes a little more complex since the device is essentially fighting gravity to operate.

18650s do lose capacity at an accelerated rate when left fully charged, its right there in Samsung's 25R data sheet.
If you try to re-cell one of DJI's batteries and the BMS loses power entirely, the chip will cease to function and the battery becomes a paperweight. People have tried with higher capacity cells and found out the hard way.

Only reason I can think they dont self-discharge is to cut down on weight and cost, self-discharge requires components (banks of resistors) to absorb the energy. Of course you can always just leave the fully charged, it just means shortened life and you having to go out and buy new batteries sooner than others.

Oh and its not "40%",  its nominal voltage as per spec sheet, approx 3.7v/cell is where you want to be. The percentage figure can vary from manufacturer to manufacturer or vendor to vendor.

Dr0ne_n00b Posted at 4-5 02:03
This post is wrong on so many levels, I'm not even sure where to begin.
18650's are not as good at current discharge as LiPos, that why they arent used generally for drones.
When a cell fails in a drill, it doesnt fall out of the sky, unlike a drone. If a torch shines a little less brighter, most people are happy to wear that consequence for having it always available and ready to operate, drones becomes a little more complex since the device is essentially fighting gravity to operate.

1. LiPos are better in discharge current but crazy bad in a life time. I have many swollen batteries... All 5 batteries of my DJI Phantom 2 been dead in 2 years. Few of them with only 20-30 cycles.
2. There are many MANY examples of repacked Mavic Mini batteries.  
As I mentioned before, I have tons of 18650 in Sony NP-F, in the gimbals, in flashlight and never keep them discharged. So there are many pros and cons as usual.

DJI Thor Posted at 4-4 01:27
Hi, Mavic Mini battery doesn't support self-discharge, please manually discharge the battery to 40% ~ 65% if you are not to use it more than10 days. Please put it on the charging hub or power it on the drone to discharge the battery. Thank you.

You gotta help us here... :-). Why do we need to discharge Li Ion batteries to half (if not using in 10 days)?

It makes no sense.  Seems like another waste of electricity.  I've had my batteries "at rest" for nearly a month with no change in storage levels.  What good is gained by discharging?

Prolonged chemistry stability, thus battery life. Rather than discharge I'd stay not charge.

I keep my batteries at around 60% now and charge them up when I am pretty sure for a next day outing.

Luka_BiH_ Posted at 4-3 22:37
All batteries LOSE capacity over time  if left fully charged or discharged!!!!!!!!!!!!!  Lipo can be damaged in few days while liion takes some more time. If you love your drone and batteries you will store them at 50% ( 40-60% ) when not using in more than few days.

ask that guy saying that mm batteries do not need to be discharged after a year what is his max flight time

Exactly. DJI actually tell you in the battery care to discharge them to 40-60% if they aren't being used for over 10 days. Batteries life depends on how you use them. Like phone batteries. People that just charge their phones every night will have their batteries degrade faster than someone that charges their phone when it gets very low.

deathsquad Posted at 4-5 13:41
Exactly. DJI actually tell you in the battery care to discharge them to 40-60% if they aren't being used for over 10 days. Batteries life depends on how you use them. Like phone batteries. People that just charge their phones every night will have their batteries degrade faster than someone that charges their phone when it gets very low.

How many smartphones can spend day and  stay with charge more than 50%? I think somebody have to prove it. Buy 2 same phones, use them in same regime but charge one only when it been discharged and disconnect straight after it's charged but leave second one at the charger all night and charge it any time. I think it's one of city legends. I believe it is more depends on quality of batteries. My 3 years-old Xiaomi Mi6 still have good battery life and I leave it charging all night while my friend already changed battery in his 3-years old iPhone. "I call it Luck" (С) See no need to discharge Mavic Mini batteries. Will see how they will stay in few years

Pashi Posted at 4-6 06:05
How many smartphones can spend day and  stay with charge more than 50%?  I think somebody have to prove it. Buy 2 same phones, use them in same regime but charge one only when it been discharged and disconnect straight after it's charged but leave second one at the charger all night and charge it any time. I think it's one of city legends. I believe it is more depends on quality of batteries. My 3 years-old Xiaomi Mi6 still have good battery life and I leave it charging all night while my friend already changed battery in his 3-years old iPhone. "I call it Luck" (С) See no need to discharge Mavic Mini batteries. Will see how they will stay in few years

Rechargeable batteries are like this. It's why it's also dangerous to go to 0% on Mavic pro batteries. There are some conditions to keeping battery health good depending on the type.

As to how you store the batteries, even Apple recommend not storing the batteries full or empty but at 50%... "Store it half-charged when you store it long term.
If you want to store your device long term, two key factors will affect the overall health of your battery: the environmental temperature and the percentage of charge on the battery when it’s powered down for storage. Therefore, we recommend the following:

Do not fully charge or fully discharge your device’s battery — charge it to around 50 per cent. If you store a device when its battery is fully discharged, the battery could fall into a deep discharge state, which renders it incapable of holding a charge. Conversely, if you store it fully charged for an extended period of time, the battery may lose some capacity, leading to a shorter battery life.
Power down the device to avoid additional battery use.
Place your device in a cool, moisture-free environment that’s less than 32° C (90° F).
If you plan to store your device for longer than six months, charge it to 50 per cent every six months.
Depending on how long you store your device, it may be in a low-battery state when you remove it from long-term storage. After it’s removed from storage, it may require 20 minutes of charging with the original adapter before you can use it." https://www.apple.com/au/batteries/maximizing-performance/

It wouldn't add any weight to the battery packs or the drone if they built a discharging circuit into the smart charger.  It would add some bulk to it and might require a heat sink to dissipate the wasted heat, but that would have been a nice feature to build into that charger for times when you do anticipate some long-term storage.

Of course the best course of action is to get some use out of the drone as the way to discharge the packs, and then be careful to only recharge to 40-50% when you're done.

So another thoughtful feature that the charger should have is an automatic "charge only to 50%" mode.  You could presumably add that to both the drone and the smart charger with just a firmware update.  New firmware doesn't add any weight.  ;)

If DJI really thinks we should store these packs at 40-50%, it would be very nice for them to give us these features to make it easier to do the right thing.

Sigmo Posted at 4-6 14:15
It wouldn't add any weight to the battery packs or the drone if they built a discharging circuit into the smart charger.  It would add some bulk to it and might require a heat sink to dissipate the wasted heat, but that would have been a nice feature to build into that charger for times when you do anticipate some long-term storage.

Of course the best course of action is to get some use out of the drone as the way to discharge the packs, and then be careful to only recharge to 40-50% when you're done.

Just charge your phone or some other device using the charge hub. I have had to do this with this corona virus lockdown going on. I am unable to fly now for who knows how long...

Sigmo Posted at 4-6 14:15
It wouldn't add any weight to the battery packs or the drone if they built a discharging circuit into the smart charger.  It would add some bulk to it and might require a heat sink to dissipate the wasted heat, but that would have been a nice feature to build into that charger for times when you do anticipate some long-term storage.

Of course the best course of action is to get some use out of the drone as the way to discharge the packs, and then be careful to only recharge to 40-50% when you're done.

"So another thoughtful feature that the charger should have is an automatic "charge only to 50%" mode.  You could presumably add that to both the drone and the smart charger with just a firmware update.  New firmware doesn't add any weight.  ;)"

How does the charger know when it has reached 50% charge? Simple answer, it has no way of knowing that, it can only detect when the battery has reached full charge, not some arbitrary percentage along the way.

The major problem is the concept of the intelligent battery. While it has some very handy features, the main drawback is that the 'intelligent' circuitry is always drawing some current, ir cannot be switched off. Therefore, if you leave a battery lying around for 3 months or more without using it, the intelligence circuit in the battery will reduce the charge in the battery to zero, and at that point you are screwed.

The simplest routine is to fully charge your battery every month or so, whether you are using it or not, then let the automatic discharge circuit drop the charge back down to storage level. Rinse and repeat.

Geebax Posted at 4-6 14:50
"So another thoughtful feature that the charger should have is an automatic "charge only to 50%" mode.  You could presumably add that to both the drone and the smart charger with just a firmware update.  New firmware doesn't add any weight.  ;)"

How does the charger know when it has reached 50% charge? Simple answer, it has no way of knowing that, it can only detect when the battery has reached full charge, not some arbitrary percentage along the way.

I discharged my mini batteries last night to two lights because we are in lockdown pretty much here in Sydney. What you say may be a good idea though. I am worried the battery health will be affected without using them for some time. Perhaps I should charge and discharge every few months?
Also, should we be discharging the remote battery to two lights also i assume? If I turn it on does it just stay on without a connection to the drone? Hmm...

Geebax Posted at 4-6 14:50
"So another thoughtful feature that the charger should have is an automatic "charge only to 50%" mode.  You could presumably add that to both the drone and the smart charger with just a firmware update.  New firmware doesn't add any weight.  ;)"

How does the charger know when it has reached 50% charge? Simple answer, it has no way of knowing that, it can only detect when the battery has reached full charge, not some arbitrary percentage along the way.

Any decent RC charger has a "Storage" function for batteries, where they stop (charging OR discharging) when cells have reached a certain voltage, so it's definitely feasible. As an example, my ISDT charger is preset to stop at 3.7V for LiIon, 3.8V for LiPo.

MM batteries automatically go into hibernation mode when cells go below 3.0V, specifically to prevent over-discharge.
Personally, I see no reason to charge them every month, quite the contrary: store them at 50-60% charge, and don't touch them until you need to use them.

120ccpm Posted at 4-6 16:06
Any decent RC charger has a "Storage" function for batteries, where they stop (charging OR discharging) when cells have reached a certain voltage, so it's definitely feasible. As an example, my ISDT charger is preset to stop at 3.7V for LiIon, 3.8V for LiPo.

MM batteries automatically go into hibernation mode when cells go below 3.0V, specifically to prevent over-discharge.

"Any decent RC charger has a "Storage" function for batteries, where they stop (charging OR discharging) when cells have reached a certain voltage, so it's definitely feasible. As an example, my ISDT charger is preset to stop at 3.7V for LiIon, 3.8V for LiPo."

That is controlling the charge with respect to the battery terminal voltage, not the percentage of charge that was suggested by Sigmo. And if any battery has a processor controlled battery management system on board, it can over-discharge the battery over a lengthy period of time due to the management circuitry consuming power.

Geebax Posted at 4-6 17:47
"Any decent RC charger has a "Storage" function for batteries, where they stop (charging OR discharging) when cells have reached a certain voltage, so it's definitely feasible. As an example, my ISDT charger is preset to stop at 3.7V for LiIon, 3.8V for LiPo."

That is controlling the charge with respect to the battery terminal voltage, not the percentage of charge that was suggested by Sigmo. And if any battery has a processor controlled battery management system on board, it can over-discharge the battery over a lengthy period of time due to the management circuitry consuming power.

That is controlling the charge with respect to the battery terminal voltage, not the percentage of charge that was suggested by Sigmo.

I think Sigmo was generically asking for the hub to be able to charge batteries to storage level. Your reply "it can only detect when the battery has reached full charge" seemed to imply that a partial charge was not possible, so I wanted to clarify that. Moreover, what really matters for storage is not the percentage of charge, but the terminal voltage of the cells. The 40-60% recommendation from DJI is just a simplification to bring the voltage in the right ballpark, as people can quickly check the charge level via status LEDs.

And if any battery has a processor controlled battery management system on board, it can over-discharge the battery over a lengthy period of time due to the management circuitry consuming power.

As mentioned above DJI says that hibernation is specifically intended to prevent over-discharge. I have no way to validate actual drain in that condition, but I bet is negligible. These batteries could potentially remain in their box for months, between production and first use.

120ccpm Posted at 4-6 20:26
That is controlling the charge with respect to the battery terminal voltage, not the percentage of charge that was suggested by Sigmo.

I think Sigmo was generically asking for the hub to be able to charge batteries to storage level. Your reply "it can only detect when the battery has reached full charge" seemed to imply that a partial charge was not possible, so I wanted to clarify that. Moreover, what really matters for storage is not the percentage of charge, but the terminal voltage of the cells. The 40-60% recommendation from DJI is just a simplification to bring the voltage in the right ballpark, as people can quickly check the charge level via status LEDs.

"As mentioned above DJI says that hibernation is specifically intended to prevent over-discharge. I have no way to validate actual drain in that condition, but I bet is negligible. These batteries could potentially remain on the shelves for months, between production and first use."

A dumb battery in this application would not be so much of a risk, but the drain on the battery via the management circuitry, while admittedly low, is enough to fully discharge a multi-cell pack, such as those used in the Phantom and other models, over a period of 3 months or so. And a fully discharged pack may never recover.

If you take a look in the Phantom forum, you will find ample eveidence of people ending up with dead packs over extended periods, and this is the cause. This is why the experienced users recommend that the batteries are fully charged every couple of months, and left to discharge via the automatic function. Leave them for a long time and you have a very much reduced chance of reviving them.

Sigmo Posted at 4-6 14:15
It wouldn't add any weight to the battery packs or the drone if they built a discharging circuit into the smart charger.  It would add some bulk to it and might require a heat sink to dissipate the wasted heat, but that would have been a nice feature to build into that charger for times when you do anticipate some long-term storage.

Of course the best course of action is to get some use out of the drone as the way to discharge the packs, and then be careful to only recharge to 40-50% when you're done.

Smartcharger discharge my batteries at 1-2% per day. I don't know is it a feature or bug, but many users not keeping  batteries in the charger. If this is a bug - it can discharge them to 0% and this will destroy them completely. Please check your charger, it is interesting to compare.

Geebax Posted at 4-6 20:59
"As mentioned above DJI says that hibernation is specifically intended to prevent over-discharge. I have no way to validate actual drain in that condition, but I bet is negligible. These batteries could potentially remain on the shelves for months, between production and first use."

A dumb battery in this application would not be so much of a risk, but the drain on the battery via the management circuitry, while admittedly low, is enough to fully discharge a multi-cell pack, such as those used in the Phantom and other models, over a period of 3 months or so. And a fully discharged pack may never recover.

That is why there's hybernation mode on MM to stop continual discharging from "smart" circuits when battery is not used for longer time.

Sigmo Posted at 4-6 14:15
It wouldn't add any weight to the battery packs or the drone if they built a discharging circuit into the smart charger.  It would add some bulk to it and might require a heat sink to dissipate the wasted heat, but that would have been a nice feature to build into that charger for times when you do anticipate some long-term storage.

Of course the best course of action is to get some use out of the drone as the way to discharge the packs, and then be careful to only recharge to 40-50% when you're done.

Actualy the hub is not a smart charger, hw upgrade would be needed for these inteligent features...

Hey guys - talking about battery, to the one using android... how long your controller will last until the REMOTE CONTROLLER battery is empty? mine last around 1 hour,.. dji support said its normal, because anroid takes a lot of battery from the remote, i should use an iphone o_O Like that I cant even use the 3rd mini battery probally anyone with the same issue?

Also my mini seems to be quite warm... talking about the drone battery it is always around 50 celcius.

The existing hub may not be very "smart", but it purports to tell us the state of charge of each battery, finds the one closest to full, and charges it first when you put a battery into it.

So whether it's truly "smart" or not, the least it could do is have a mode to charge each battery to "two lights" and then stop.

And it would have been nice if it also had a smart discharge system built in, as well.  Obviously that would require additional hardware.

Extra nice would be a charger hub with a storage mode that would discharge all of the batteries as needed, charge any as needed, and intelligently charge them all, as needed, over time to maintain them at a safe long-term level for months or years if you put it in that long-term storage mode and then simply left the batteries in it with it plugged in.

Obviously that's more than a firmware update.  But it would be a nice product.  Where I live, it's windy and/or cold all winter.  Six months of "no fly".

Sigmo Posted at 4-7 09:35
The existing hub may not be very "smart", but it purports to tell us the state of charge of each battery, finds the one closest to full, and charges it first when you put a battery into it.

So whether it's truly "smart" or not, the least it could do is have a mode to charge each battery to "two lights" and then stop.

Agreed, it would be a nice improvement for a v2 version of the hub.

virtual Posted at 4-7 03:31
That is why there's hybernation mode on MM to stop continual discharging from "smart" circuits when battery is not used for longer time.

Yeah, but it does not work over a long time. No matter what you say, the 'smarts' cause battery drain. There are legions of people who have useless batteries because they left them unattended for too long.

Li-ion batteries were designed for Nuclear weapon triggers and designed to be stored long time at charge , but saying that I have found that the MM battteries drop over time but not by a great amount.

In case nobody knows the Phantom 4 DJI Charger has a switch for full or storage charge. I don't know why they dropped this feature.

DeadlyRaptor Posted at 2020-10-29 03:19
Li-ion batteries were designed for Nuclear weapon triggers and designed to be stored long time at charge , but saying that I have found that the MM battteries drop over time but not by a great amount.

I doubt nuke trigger take much power to activate so some degradation would be ok for Li-Ion. I have the same experience with mavic mini batteries. They do drain over time. What DJI put in their manual is simply false. All batteries will self-discharge somewhat over time via its internal chemistry so no external conduction is required. It is even faster if the battery has a BMS onboard because the circuit will drain power slowly.

Geebax Posted at 2020-4-7 14:12
Yeah, but it does not work over a long time. No matter what you say, the 'smarts' cause battery drain. There are legions of people who have useless batteries because they left them unattended for too long.

I had cells charged to 100% 3 months ago and now they show 75%. If this https://www.powerelectronics.com ... ection%20circuitry. is to be believed, then 5% self-discharge on the first day + 3% self-discharge per month and 3% discharge via BMS per month puts us at 23% capacity drop at the after 3 months storage. That is actually fairly close to what my experience is. I am sure DJI is not that stupid and when they say battery goes to hibernation it actually does. My guess is the BMS chip actually shuts down once voltage drops below certain level triggering the "hibernation". But the problem then comes from the 3% per month self-discharge which is just from the chemistry neutralizing itself inside the cell. Hibernation is not gonna make the cell invincible and people will end up with dead cells when they leave it long enough for the voltage to drop to irrecoverable level.
So I think perhaps having the cells at 100% is not as bad as leaving them low for too long. 100% will quickly degrade and the cell will spend a long time in storage charge state range. But if one leaves cell long time on already low charge state, the cell would be damaged beyond recovery for sure. That said I think it is still good to keep the cells away from 100% for storage. 40%-75% and check regularly. If you are lazy like me then full up and let it drop is probably not that bad...
I got some cells stored at 100% for a year now. Will go out and so some hover test to see if battery degraded much.

Not quite a year. Turned out to be only 8 months of storage starting from full charge. No significantly different performance compared to before. I still get a very similar minutes/battery% as before. Li-ion is not invincible though. I had my laptop li-ion died on me and I think it is from constantly charged to 100% via trickle charge but that is so extreme and almost will never happen to drone battery. Having battery stored at half charge is good for long term but just in case you stored it full it is not that detrimental. Just don't keep it in high charge state for too high too long. Never leave the cells too long no matter the charge state.