Sudden battery power-drop in-flight

Tufargon · May 8, 2018

I usually do it within like 24 hours and this time was about 2 days since the charge. Autel has got back to me to get them more information but it seems as though the one big drop may be a problem. Need to recharge them and take a couple screenshots for them.
I have flown many times with a 4-5 day old charge with no problems though and never had this happen.

yrless · May 8, 2018

ovrszd said:
I have four batteries, three of which have displayed this issue. The chances that all three of those batteries went "bad" at the same time is extremely small.

I think this is a firmware problem. I'm going to try draining my batteries and recharging. If that doesn't work then I guess I'll do what you did and try for new batteries. Gonna be a PITA to go thru all that three times....

Just use caution with your definition of "draining." Lipo's pulled below 3.2 volts per cell under load are instant paper weights.

HiloHawaiian · May 8, 2018

ovrszd said:
Are you guys "fresh" charging your batteries just before flight? Reason I ask is I've heard it said that eliminates this problem..... My last few flights I've done this with no problems. Not pimping it as a solution. Just asking??

Yes, I think you’re right. I started doing that, AND deep cycling them around 18-20 cycles religiously and it hasn’t happened since......fingers crossed.

HiloHawaiian · May 8, 2018

yrless said:
Just use caution with your definition of "draining." Lipo's pulled below 3.2 volts per cell under load are instant paper weights.

Yup...You need to do it exactly as Autel dictates in the battery flyer in the box...

Cori · May 8, 2018

Hi Hilo. It's good to hear that you are far from the volcano action in Hawaii. Do you feel any earthquakes in your area?

I've worked with Lithium batteries since their inception. Insomuch, I would strongly recommend that you not use any device (other than the discharge electronics in the drone battery) to discharge your battery with. Mr. yrless (above) is right on. Each and every Lithium battery is designed around certain, and very specific parameters (needed/operating current draw, desired charging time, and discharge rates). Modifying any of those parameters can not only result in battery failure, but, with Lithium batteries, it can result in an explosion or a flame-up. I'm not saying that will happen. But, the risk that it will happen is greatly increased. With Ni-Cad and NickelMetalHydride batteries, there was much more flexibility. One might ask, why then, are Lithium batteries so popular now? The answer is that they (lithium) deliver more current, more evenly, for a longer period of time. Also, as lithium battery current is consumed, voltage does not decrease, which is very preferential to the electronics it is powering. I personally, would recommend against trying to second-guess the operation and capabilities of the discharge electronics and firmware in your drone battery.
Keep the beautiful Hawaii pictures coming. Not only are you in a beautiful place, but you are fortunate to have a drone that helps you share such a place with others!

HiloHawaiian · May 9, 2018

Cori said:
Hi Hilo. It's good to hear that you are far from the volcano action in Hawaii. Do you feel any earthquakes in your area?

I've worked with Lithium batteries since their inception. Insomuch, I would strongly recommend that you not use any device (other than the discharge electronics in the drone battery) to discharge your battery with. Mr. yrless (above) is right on. Each and every Lithium battery is designed around certain, and very specific parameters (needed/operating current draw, desired charging time, and discharge rates). Modifying any of those parameters can not only result in battery failure, but, with Lithium batteries, it can result in an explosion or a flame-up. I'm not saying that will happen. But, the risk that it will happen is greatly increased. With Ni-Cad and NickelMetalHydride batteries, there was much more flexibility. One might ask, why then, are Lithium batteries so popular now? The answer is that they (lithium) deliver more current, more evenly, for a longer period of time. Also, as lithium battery current is consumed, voltage does not decrease, which is very preferential to the electronics it is powering. I personally, would recommend against trying to second-guess the operation and capabilities of the discharge electronics and firmware in your drone battery.
Keep the beautiful Hawaii pictures coming. Not only are you in a beautiful place, but you are fortunate to have a drone that helps you share such a place with others!

Yes, you can feel the big 6.9 quakes, but volcanic quakes tend to be more localized and less severe than fault-based quakes of the same R scale strength. I dunno why, but a 6.9 in the SF Bay Area would do some damage. This one really didn't...

Jagerbomb52 · May 9, 2018

Talking to Jacob Autel Customer Support today these batteries do not have a set C rating marked on them because you can change the days to discharge in the app, there isn't a set discharge rate. The default setting in the battery is 6 days, but you can change it to anywhere from 2 to 10, depending on how fast you'd like them to discharge. Also for discharge you can use the Xstar battery to charge your RC controller and is a recommended alternative from Autel for the deep discharge cycle instead of flying it down to 7%.
When I asked about balancing the battery and when it occurs he told me it was all good! The chip inside the smart battery keeps all of the cells balanced while charging as well as discharging, so you don't have to worry about that. When you're pulling power from the battery to charge the controller, that chip in the battery keeps them all balanced as well during that process. He said the batteries have a battery back charge system allowing it to charge your RC controller. So if you follow basic Lipo safety and discharge at a low setting so you are not over stressing the battery I would say these after market dischargers are safe but that is totally up to you to go this route. One thing that Cori and I agree on is lipo safety and there are many good sites to learn the basics.
Here is a good place to start for the basics
A Guide to Understanding LiPo Batteries

If you really want to learn more there is a lot of good info here
Basic to Advanced Battery Information from Battery University

I do think not charging to early is the key. Also look at your cells under load. I have one battery with a bad cell and under load it drops more then the others which can cause this.

HiloHawaiian · May 9, 2018

Agustine said:
Talking to Jacob Autel Customer Support today these batteries do not have a set C rating marked on them because you can change the days to discharge in the app, there isn't a set discharge rate. The default setting in the battery is 6 days, but you can change it to anywhere from 2 to 10, depending on how fast you'd like them to discharge. Also for discharge you can use the Xstar battery to charge your RC controller and is a recommended alternative from Autel for the deep discharge cycle instead of flying it down to 7%.
When I asked about balancing the battery and when it occurs he told me it was all good! The chip inside the smart battery keeps all of the cells balanced while charging as well as discharging, so you don't have to worry about that. When you're pulling power from the battery to charge the controller, that chip in the battery keeps them all balanced as well during that process. He said the batteries have a battery back charge system allowing it to charge your RC controller. So if you follow basic Lipo safety and discharge at a low setting so you are not over stressing the battery I would say these after market dischargers are safe but that is totally up to you to go this route. One thing that Cori and I agree on is lipo safety and there are many good sites to learn the basics.
Here is a good place to start for the basics
A Guide to Understanding LiPo Batteries

If you really want to learn more there is a lot of good info here
Basic to Advanced Battery Information from Battery University

I do think not charging to early is the key. Also look at your cells under load. I have one battery with a bad cell and under load it drops more then the others which can cause this.

Great info, thanks!

yrless · May 9, 2018

Just wondering if it's possible to see lipo cells puffing up inside these plastic enclosed battery packs...I have a bunch of packs I use for 250 racers that have obviously swelled so I've sidelined them but do these sealed packs puff out in such an obvious manner? Anyone have experience like this with Autel or DJI Batts?

Jagerbomb52 · May 9, 2018

Yes they do. The little black circles will puff out. And if you lay the flat part on a table they will start to rock if you push on one end. Hard to tell sometimes but they do.

Jagerbomb52 · May 9, 2018

ovrszd · May 10, 2018

I've had two swell so much they wouldn't fit in the drone.

yrless · May 10, 2018

ovrszd said:
I've had two swell so much they wouldn't fit in the drone.

Wow...maybe that was all for the best...who knows what that pack might have done in the air under high current draw

Jagerbomb52 · May 10, 2018

Just remember if you get a replacement battery for any reason, that new batteries warranty starts on the day you receive it. 1 Year or 200 charges from the time of replacement.

0ldwrangler · May 14, 2018

I did the upgrade recently, don't know if that made any difference. Anyway I flew two days ago. Linked up the controller to the drone and that voice told me the battery was too cold and told me to hover about 4 feet until the battery warmed up. I did so and the screen said, safe to fly. This was in 70 degree weather with a fully charged battery. I took off and went up about 200 feet over the lake in front of my place and I get a low battery warning, landing now. No control response, it is now sleeping with the fishes. Anyone interested in a controller, charger, and case?

Jagerbomb52 · May 14, 2018

Have you talked to Autel? They might work with you if it is under warranty. Even if its not I have seen them replace quads because of this issue.

0ldwrangler · May 14, 2018

Agustine said:
Have you talked to Autel? They might work with you if it is under warranty. Even if its not I have seen them replace quads because of this issue.

I am in the process with Autel now. I reviewed my last flight, at one minute and 45 seconds I had 11minutes of flight time left and 80% battery, at one minute and 46 seconds I had one minute of flight time and 8% battery. splash..............

Jagerbomb52 · May 14, 2018

Hope it all works out in a good way for you

Tufargon · May 15, 2018

Well during the process of trying to find out what happened Autel confirmed I had a bad battery. That was not the whole reason of the drop though. The main reason was It was not fully charged when I took off. That's why both batteries did it and one way worse than the other (because the battery was bad). So long story short they are sending me a new battery even though I did not have a receipt and it was purchased in December 2016. I guess they replaced it because it only had 14 charges. Goes to show Autel is a very stand up company when it comes to CS.