Battery Shelf Life

[ADOC]

Hehe very true.
Dont forget the Outbreak of "Droners Thumb"

 

[herein2021]

Basically I have reached the conclusion that surpassing current battery technology is very difficult. Each "breakthrough" seems to come with a lot of caveats such as they can't produce it at scale, it will burn your house down if it gets too hot/cold, it will be unrealistically expensive, etc. It would be great to see something make it to market but I definitely would not hold my breath.

Hehe very true.
Dont forget the Outbreak of "Droners Thumb"

That would definitely become a real thing. I also don't think the people wanting 2-3hr flight times really realize how exhausting that would become. Constantly watching the screen, on the lookout for hazards, watching all of the indicators to ensure nothing is going wrong while it is airborne; its rare that my EVO is in the air more than 10min; and lets not forgot the YT morons who would post videos taking off and landing in a different city while crossing 10 different flight restricted areas.

 

[ADOC]

My background to RC is Thermal Glider and Slope Soarers, we never had regrets over hrs of flight. But it was of course completely different, gently soaring, sometimes doing a XC flight, chasing our craft via car or walking along coastlines. Limited flight times and screen dependent operation, VLOS or Not, is so new to me. I find the biggest hurdle with drones right now, as I learn, is Flight Time management, so if batteries could last 1hr, I'd be very happy indeed, because at the moment I waste a lot of flight time setting up my "mission", and the inability on current software to fly Waypoints and save more flight time, annoyes me a lot.

 

[uas_gian]

Just out of curiosity, when I top up a resting Autel drone battery, let's assume from about 45% to 75% only to be placed back on the shelf, does this count as a loading cycle for the internal battery management?

Furthermore now almost a year later, I can confirm those resting batteries, after being topped-up once every 3 months, still seem totally OK. No bulging cells and perfect peak charge. Some of them will pass the 3 year age mark this summer. I guess we will see or know what happens next.

 

[herein2021]

Just out of curiosity, when I top up a resting Autel drone battery, let's assume from about 45% to 75% only to be placed back on the shelf, does this count as a loading cycle for the internal battery management?

Furthermore now almost a year later, I can confirm those resting batteries, after being topped-up once every 3 months, still seem totally OK. No bulging cells and perfect peak charge. Some of them will pass the 3 year age mark this summer. I guess we will see or know what happens next.

I would not do that because the discharge circuit is just going to discharge it back down to 50% within 6 days. If anything you would only want to top up to around 60% if your previous flight discharged the battery to below 50%, anything more than that and the discharge circuit will just bring it back down to 50% anyway.

I have never topped up mine and I am past the 3yr mark now with no problems.

 

[uas_gian]

I would not do that because the discharge circuit is just going to discharge it back down to 50% within 6 days. If anything you would only want to top up to around 60% if your previous flight discharged the battery to below 50%, anything more than that and the discharge circuit will just bring it back down to 50% anyway.

I have never topped up mine and I am past the 3yr mark now with no problems.

As far as I have understood, the discharge process of the internal battery management, discharges the battery down to 60% (not 50%). This process starts after 6 or 10 days when the battery is not being used, the number of days is depending on the settings. If the battery sits on the shelf for 3 months its charge gradually goes down below 50%. A value below 50% means only two lights light up and the second light is blinking. If the charge is above 50% three lights show up and the third light is blinking. If the charge is exactly 50% no lights are blinking, in that case just 2 of 4 light up, and the battery is safe. So My approach is to check once every month and top up for a few minutes when the charge gets below 50%. This then leaves a battery charged at something between 60-70% for 6 - 10 days. I feel comfortable with this, making sure those batteries are taken care of when not being used for flights.

 

[herein2021]

As far as I have understood, the discharge process of the internal battery management, discharges the battery down to 60% (not 50%). This process starts after 6 or 10 days when the battery is not being used, the number of days is depending on the settings. If the battery sits on the shelf for 3 months its charge gradually goes down below 50%. A value below 50% means only two lights light up and the second light is blinking. If the charge is above 50% three lights show up and the third light is blinking. If the charge is exactly 50% no lights are blinking, in that case just 2 of 4 light up, and the battery is safe. So My approach is to check once every month and top up for a few minutes when the charge gets below 50%. This then leaves a battery charged at something between 60-70% for 6 - 10 days. I feel comfortable with this, making sure those batteries are taken care of when not being used for flights.

I have never seen it documented that clearly anywhere, my personal experience is when it does discharge it does so within 6 days and stops around the 50% mark, your battery FW may act differently. Autel's own official documentation does not list the actual level anywhere and just states it discharges to a "safe level"; for LiPo's that optimal level is between 40% and 60% with most vendors opting for 50% to provide room for error. I also have at least one battery that doesn't seem to discharge at all and will sit at the level it was last left at.

Also, as per their documentation, they recommend once a month fully charging the battery which includes a balancing cycle vs just recharging to 60%. I am almost at the 3.5yr mark with my batteries and they all show around 31min of flight time remaining before takeoff, when they were brand new they showed around 33min of flight time remaining so losing 2min in 3yrs is pretty acceptable to me. I have never topped them off if they drop below 50% but I also rarely deeply discharge them or discharge them below 50% since my flights typically do not last very long.