I'm looking for guide to maintain DJI batteries for MA2 and found this.
https://store.dji.com/guides/battery-care-important-think/

Another thing that I do every month to even further take care of and extend life is called a deep cycle. First, fully charge battery. Then fly it until low battery and bring it back to you. Then when it hits critically low, resist the landing by using throttle and wait until the battery reaches 5%. Then immediately shut it off and wait 30 minutes for the battery to cool down. Then fully charge it. This will give the battery’s cells a reset and lengthen the life of it.

Sparkflier Posted at 5-30 11:55
Another thing that I do every month to even further take care of and extend life is called a deep cycle. First, fully charge battery. Then fly it until low battery and bring it back to you. Then when it hits critically low, resist the landing by using throttle and wait until the battery reaches 5%. Then immediately shut it off and wait 30 minutes for the battery to cool down. Then fully charge it. This will give the battery’s cells a reset and lengthen the life of it.

Great. Thanks for the tips. Added value

DJIMNYD Posted at 5-30 17:24
Great. Thanks for the tips. Added value

I stored my Spark for 2 years and now the batteries do not charge. Green LED flashes a few times and then stop

djiuser_d5qPU5n1Eq93 Posted at 5-30 18:20
I stored my Spark for 2 years and now the batteries do not charge. Green LED flashes a few times and then stop

Hi,
I'm still new with DJI MA2. Recently there is discussion about charging battery for new MA2 just after unboxing it. Batteries wont charge or power on. I do not know whether this relevant to you or not. See the link for self explanatory.
https://forum.dji.com/forum.php? ... &extra=page%3D1

Sparkflier Posted at 5-30 11:55
Another thing that I do every month to even further take care of and extend life is called a deep cycle. First, fully charge battery. Then fly it until low battery and bring it back to you. Then when it hits critically low, resist the landing by using throttle and wait until the battery reaches 5%. Then immediately shut it off and wait 30 minutes for the battery to cool down. Then fully charge it. This will give the battery’s cells a reset and lengthen the life of it.

Forgive the question but this seems to conflict with other battery advice on this forum where several members suggest avoiding deeply discharging your batteries - trying to leave about 30% charge at the end of the flight - as this will prolong the life of the batteries.
I’m a novice but I’m now confused as to the best approach.

Sparkflier Posted at 5-30 11:55
Another thing that I do every month to even further take care of and extend life is called a deep cycle. First, fully charge battery. Then fly it until low battery and bring it back to you. Then when it hits critically low, resist the landing by using throttle and wait until the battery reaches 5%. Then immediately shut it off and wait 30 minutes for the battery to cool down. Then fully charge it. This will give the battery’s cells a reset and lengthen the life of it.

Thanks for the tip

I sort of had to laugh when I saw this subject.  My real job is a technician in a two way radio shop.  We deal with hundreds of batteries for portable radios.  I can tell you that batteries will drive you nuts.  Likely half the users that come into the radio shop with a portable radio not working right - it's the battery.
Yes, you can murder a battery by abusing them, and I have seen people who take good care of their batteries have them last two to three times longer than average.  Different battery chemistries have different requirements.  The deep cycle requirement was a huge requirement for NiCad batteries.  Less so with MiMH, and very little with Lithium.  Even within the Lithium family of batteries, there are different chemical formulations, and some of those have very different requirements.  My general recommendation is to follow whatever recommendation the manufacturer makes for that particular battery.  What works well for one battery may be very bad for another.  The manufacturers have the ability to test hundreds or thousands of batteries to confirm what works.  You likely don't want to go through hundreds of batteries testing them!

K6CCC Posted at 6-4 14:26
I sort of had to laugh when I saw this subject.  My real job is a technician in a two way radio shop.  We deal with hundreds of batteries for portable radios.  I can tell you that batteries will drive you nuts.  Likely half the users that come into the radio shop with a portable radio not working right - it's the battery.
Yes, you can murder a battery by abusing them, and I have seen people who take good care of their batteries have them last two to three times longer than average.  Different battery chemistries have different requirements.  The deep cycle requirement was a huge requirement for NiCad batteries.  Less so with MiMH, and very little with Lithium.  Even within the Lithium family of batteries, there are different chemical formulations, and some of those have very different requirements.  My general recommendation is to follow whatever recommendation the manufacturer makes for that particular battery.  What works well for one battery may be very bad for another.  The manufacturers have the ability to test hundreds or thousands of batteries to confirm what works.  You likely don't want to go through hundreds of batteries testing them!

Hi K6CCC,
Thanks for sharing the information. I agreed about the manufacturer know better about their battery.
Stay safe and have fun.

Smashey1 Posted at 5-31 13:24
Forgive the question but this seems to conflict with other battery advice on this forum where several members suggest avoiding deeply discharging your batteries - trying to leave about 30% charge at the end of the flight - as this will prolong the life of the batteries.
I’m a novice but I’m now confused as to the best approach.

If you read any LiPo battery manufacturers technical literature, you will get the best advice.
The things you will learn from them are:-
The cells are a mix of chemicals that start degrading the moment the cells are assembled, unlike a machine, for example. Use them or don't use them, they are always degrading.
The chemical reactions in the cells have predictable limits. Overcharging and over-discharging will rapidly damage the cell. Overcharging is hard to do with the battery electronics that control the process, but charging while warm or hot will tend to cause swelling from gasses in the cell. The swelling usually allows the cell layers to seperate, leading to localised overheating in the cell or sudden electrical failure. The gas is flamable.
Depending on what level the shut-off is in the cell and that is set by the battery control circuit ,  taking the remaining charge down to zero% risks stopping the battery from recharging, at all. Very low charge states always allows lithium to be deposited on the electrode and this is an irriversable barrier to the chemical process. This will also reduce the power capacity of the cell.
Whilst I wouldn't go below 30%, other users seem to do so and with no reported failures. That isn't contradicting the known chemistry, but more to do with the % of capacity the battery claims. It isn't a real measurement, like 1Km is.
Depending on the model of drone, the battery may be undersized for someone who wants high speed. The MP seems sized about right, in my view, unless you use sports mode predominately in a hot climate. A battery that has to pump out full power most of the time and overheats inside will soon fail.
Do check these facts with a  manufacturer's site.

K6CCC Posted at 6-4 14:26
I sort of had to laugh when I saw this subject.  My real job is a technician in a two way radio shop.  We deal with hundreds of batteries for portable radios.  I can tell you that batteries will drive you nuts.  Likely half the users that come into the radio shop with a portable radio not working right - it's the battery.
Yes, you can murder a battery by abusing them, and I have seen people who take good care of their batteries have them last two to three times longer than average.  Different battery chemistries have different requirements.  The deep cycle requirement was a huge requirement for NiCad batteries.  Less so with MiMH, and very little with Lithium.  Even within the Lithium family of batteries, there are different chemical formulations, and some of those have very different requirements.  My general recommendation is to follow whatever recommendation the manufacturer makes for that particular battery.  What works well for one battery may be very bad for another.  The manufacturers have the ability to test hundreds or thousands of batteries to confirm what works.  You likely don't want to go through hundreds of batteries testing them!

I agree with everything you said.
The other thing the OP should bear in mind, phones, radios and laptops will never fall out of the sky because of a battery failure. A drone always will.

Once the drone is set up and able to fly maintaining the batteries are the most important thing when not flying

以下是维护无人机电池的两个提示：

1.如果您超过10天不使用电池，请将电池放电至其存储容量的40-65％，以延长其使用寿命。
2.电池完全放电后，请勿将其长时间存放，以免电池进入过度放电状态，否则可能损坏电池并使其无法使用。

从Grepow  https://www.grepow.com/