Hi,
Went through a surgery and stop flying my Phantom 4 Pro.
It was almost a year. And- yes - I had no chance to took precautions like discharging the batteries.So is my fault.
I checked my stock of -new batteries out of the box.All dead. Not one light.

I asked support DJI, to answer what to do and how I could recover a total of 16 Phantom 4 Pro batteries,and 6 of my Mavic Pro...

The kindly answered ,giving me instructions on how to waste such batteries...
I understood, and I did it..! My fault and all 22 batteries to trash..

I have -also - One Inspire 1 and One Inspire 2...! Purchased almost same time as my Phatom 4 Pro and my Mavic Pro.
These Drones (Inspire 1 and 2) suffered -also my unattention while my health recovery - for almost a year,same as Phantom 4 Pro.

Nebertheless - the batteries of these 2 drones (Inspire 1 and 2) - are working perfect, as from the beginning...

Some considerations :

- ¿ are the Phantom 4 and Mavic Pro batteries built -with cheaper or lower quality standards -than the batteries for the Inspire Class ?

-  The amount of  “ plastic “ or whatever the material is to waste its...huge..


- No  complains for the money involved in 22 batteries.
  
   But ¿ how comes they worth just - nothing - even if they are “new“ just out of the box ,but dead.?
   Factory will re-use dead batteries ,I guess..


- ¿ what would be the precutions to take - when purchasing a bettery through a dealer- ?
  ¿ How to trust they will sell you a fresh battery...??

-This “dead battery syndrome“  doesnt happen to Yunnec Typhoon H, or Hubsan X4  nor 3DR Solo Drones..   
In same circumstances - these drones brands -doesnt have this dead battery syndrome..


The problem is with Phantom 4 Pro and Mavic Pro Drones..

I hope you didn't put 'em in the trash

Be sure to ask, before buying more batteries ,,,  what the MFG Date is......I would hope no more than 6 months old, New In Box.

Good luck,  and to me,  THAT HURTS......not counting your own recovery.  I hope your health is better now, and continues!!

Randy

rwynant V1 Posted at 2-9 17:20
Be sure to ask, before buying more batteries ,,,  what the MFG Date is......I would hope no more than 6 months old, New In Box.

Good luck,  and to me,  THAT HURTS......not counting your own recovery.  I hope your health is better now, and continues!!

Thanks -so much -for your post Randy ..
It was a heart surgery , but its better now..
Wish I knew " where to look" an expiration date on a battery..! In any case its....my fault..! Iam going into my 80's and not fan of " computing stuff "..! Guess also shouldnt buy too many batteries !

Elwort Posted at 2-9 17:42
Thanks -so much -for your post Randy ..
It was a heart surgery , but its better now..
Wish I knew " where to look" an expiration date on a battery..! In any case its....my fault..! Iam going into my 80's and not fan of " computing stuff "..! Guess also shouldnt buy too many batteries !

Oh MY,   I am so glad you are still with us!!  I'm not all that young....sotospeak.....

Just ask the seller what the MFG Date is.....and then SHOW you before opening package.

Good luck and ALL the BEST!!  Fly as much as you can!!

Randy

I e had my p4pro batteries on charge for a few months in standby mode on the multiple battery charger. Today I took them off to use and they will not turn on or take a charge. Are they completely useless?

If not flying, you should still occasionally check your flight packs for discharge activity, and charge them to atleast 50% voltage.

I would have had someone kindly check on mine, if I knew they would be unused for an extended period of months.

RedHotPoker

Jon Logan Posted at 2-10 12:50
I e had my p4pro batteries on charge for a few months in standby mode on the multiple battery charger. Today I took them off to use and they will not turn on or take a charge. Are they completely useless?

You should never leave batteries on a charger for any reason.


RedHotPoker

22 DJI batteries would be life savings for many. Hahaha

Glad you are better now, and moving forward.


RedHotPoker

Laptop batteries, which are now Lithium Ion, are not the same as the old Nickel Cadmium batteries of past generations.

The old Ni-Cad batteries did have to be discharged periodically to remove the "memory" from the battery.

There is no need to fully discharge the battery before charging it.

Lithium Ion batteries actually last longer if you keep them topped off, as fully discharging them can shorten the life.

Just plug the laptop in when you are near and outlet, and leave it plugged in even if it is fully charged. New laptops automatically shut off the charging voltage to the battery once it senses the battery is fully charged. So there is no risk of overcharging the battery.

Leaving it plugged in will not harm the computer or the battery.