Drone batteries to be stored at 40%?

softdown
softdown Solar Expert Posts: 3,812 ✭✭✭✭
Sounds nuts considering that only gives a few minutes of flight time considering that you should dock when approaching 20% battery life. Perhaps drone batteries are much different? Perhaps they seek to sell more batteries that are needed when stored batteries are almost unusable until charged up?

These little batteries cost at least $100 - shocking considering their popularity and small size. Referring to Mavic Mini batteries - the Mavic Mini is a very, very popular and affordable drone at $400.

Hoping somebody knows the real story on this. Attempts to gain a couple meager months of viability? A rock solid effort to double longevity? Or an effort to sell more high margin batteries?

Right now I plan to store mine at a higher charge than 40%. I don't want to lose once in a lifetime opportunities because I was coddling batteries for another few percentage points of longevity. I may be wrong - perhaps drone batteries really are unicorns deserving of very, very special treatment.
First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    For any flying machine, weight is a critical factor. Your machine's batteries maybe closer to Unicorns (or winged horse family like Pegasus) than the average battery.

    Probably not storing over 80% State of Charge will be a good cross between longer life and still having a battery pack ready for use at a moments notice.

    Keeping batteries cool/cold helps too (not stored on a car's dashboard under the hot sun). The old "for every 10C/18F rise in temperature, life is cut by 1/2--For every 10C drop in storage temperature, a 2x longer life).

    Many decades ago, my father tried to keep (alkaline) batteries in the refrigerator for longer life... As I remember, we probably ended up with just more cold/dead batteries... So, I am not sure I would suggest storage in the fridge (humidity, a bit of thermal cycling and such--Usually not good for batteries/electronics).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    With lithium batteries it is recommended to not store at a fully charged state but rather a lesser %, around 40%  sounds right, chemistry dependent, self discharge is very low, keeping them cooler may reducethe self discharge to some degree. Just don't use them until the temperature has stabilized to something like room temperature.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    I have 36 18650 3.7 volt lithium bought in 2016 and stored cool. Showing 3.8 volts. I'm thinking that is close to ideal storage voltage. Was going to charge up some then changed mind with 3.8 volt reading.
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    You need to confirm the chemistry and or the mfg specifications.

    Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset