Hello All,

I was hoping to find out if anyone can tell me the best way to store the DJI phantom batteries.  I have a P2, I started doing a bunch of free lance work over the summer and needed to have 6 batteries on hand at all times.  

The season is slowing down now and I wanted to know if I need to discharge the batteries completely or leave a 5-10% charge in them.

Don't discharge them completely! Completely discharging LiPo batteries is a good way to never get them to charge up again. There's a section here on LiPo storage which is pretty useful.

lipos need to be stored between 40 and 55 %

Please check the instructions on the User Manual:

jmtw000@gmail.c Posted at 2014-11-11 03:12
Don't discharge them completely! Completely discharging LiPo batteries is a good way to never get th ...

Thanks for the LiPo link. Excellent information that everyone should read. It should actually be a Must read at the top of this forum.

Thanks for all the info guys!   

DJI-Sophie Posted at 2014-11-11 09:55
Please check the instructions on the User Manual:

I was told never discharge the battery completely at all as it will never get charge again. But based on DJI recommendation to charge and discharge completely once every 20 charge/discharge cycle to optimise battery life spend, I am actually quite confuse between the two theory. Can you kindly explain?

sukiat88@hotmai Posted at 2014-11-11 23:54
I was told never discharge the battery completely at all as it will never get charge again. But ba ...

This applies to standard "dumb" lipos.
Completely discharging a standard lipo..completely discharges it - something you do not want to do.
Discharging the smart battery to "0%" is not really a complete discharge - there's still about 15-20% of a safe reserve you don't see in your battery percentage indicator.

So going down to 0% doesn't physically drain your smart battery to an unrecoverable level.

sukiat88@hotmai Posted at 2014-11-11 23:54
I was told never discharge the battery completely at all as it will never get charge again. But ba ...

The discharge below 8% every 20 charges is not really a battery life enhancer.  It's a re-calibration cycle for the  inteli logic since a LiPo loses some capacity every discharge/charge cycle as well as over time and a lower discharge allows for more accurate measurement of the available capacity during the next charge cycle.
Furthermore the integrated inteli circuit won't allow you to drop the battery to dangerous discharge levels (or at least it's not supposed to if it works correctly) and will shut off the battery before that.
  

swomilan Posted at 2014-11-12 00:48
The discharge below 8% every 20 charges is not really a battery life enhancer.  It's a re-calibrat ...

Excellent explanation. Thanks swomlan.

Thanks to all for the advice.

skyhighdiver Posted at 2014-11-11 07:51
lipos need to be stored between 40 and 55 %

That depends what the 40-55% is based on.  The generally mentioned starting long term storage cell voltage for a LiPo is around 3.7- 3.85V per cell  (total 11.1-11.55V for a 3S like the P2 Battery).  At this charge level the over time aging process of the LiPo is minimized with room for self discharge during long storage times.  For short term storage (couple of days or a couple of weeks)  you won't need that large room for self discharge and cell voltages can be lower.  

With the new battery firmware v2.6.0.0, the auto-discharge function will activate itself after 10 days receiving no operation. The battery will automatically discharge to a safe level (50%-60%) and then go into storage mode. Try to store your battery in a mild environment with near room temperature. Avoid store it under high temperature. High temperature is the killing factor storing lithium polymer batteries.