Hello and thank you for reading about my problem.

I haven’t used my Mavic Pro for a couple of months over the winter and now that the nice weather is here, I am trying to get it into the air.

I wanted to see what the current firmware was on the controller and aircraft and I tried to start it up but the controller was at 4% and would not connect. Each of my three aircraft batteries appeared to have some power, they all had two lights when the aircraft started. But since I had to charge the controller, I put all three batteries into their charger as well. I am using only DJI equipment that came with the “Fly More” kit.

Once one battery completed its charge, I removed it from the charger and placed it into the aircraft. I connected with the controller and after the initial startup I received a “Battery Err” on the controller and in the DJI Go App (screenshot below).

By this time the second battery completed charging. I tried the second battery and had the same problem. Wondering if the charging process somehow damaged the batteries I quickly removed the third battery from the charger before the charging process was complete. It does not report an error but is not fully charged.

I used the working battery to check the firmware and it updated to v 01.04.0300 for both the aircraft and the controller. I know that the batteries also have firmware but I am not sure what it is and the error may prevent the aircraft from updating the battery.

I am posting this before I have tried any other troubleshooting efforts to ask what process I should follow to determine the problem/solution. Maybe DJI has a help video somewhere that discusses this issue?

Thank you very much in advance for any help that may help me correct this situation.

Screen 03

Screen 02

Screen 01

Hello Again

So while I was waiting to see if someone could help me, I placed the battery with the error in the Mavic Pro and let it run until the battery showed just one light flashing. I removed it from the Mavic Pro and placed it in the charger. I have read that one suggestion is to cycle the battery (discharge/recharge). When finished charging, there was just the top light flashing two times, I imagine it was warning of an error.

I placed it in the Mavic Pro and again it is showing a "Battery Err". It is fully charged and I have attached the new screenshots;

01

If someone could suggest something else I could try, I would really appreciate it. Thanks.

R_Adams Posted at 2018-4-23 11:17
Hello Again

So while I was waiting to see if someone could help me, I placed the battery with the error in the Mavic Pro and let it run until the battery showed just one light flashing. I removed it from the Mavic Pro and placed it in the charger. I have read that one suggestion is to cycle the battery (discharge/recharge). When finished charging, there was just the top light flashing two times, I imagine it was warning of an error.

Hi.

The cells in your battery are not even charged. The difference between the eats cells must not exceed 0.1 volts. You must charge your batteries up to 100% to equalize the cells. Remember to charge the batteries to 100% both before and after you are flying.

Regards Leif.

Landbo Posted at 2018-4-23 11:35
Hi.

The cells in your battery are not even charged. The difference between the eats cells must not exceed 0.1 volts. You must charge your batteries up to 100% to equalize the cells. Remember to charge the batteries to 100% both before and after you are flying.

Thank you very much for your suggestion. I put both batteries back in the charger again to see if they would charge to 100% as you have suggested. After about two minutes both batteries stopped charging and have their second light flashing twice. I'll assume that the batteries are still having an issue.

May I ask how do I charge the batteries to 100%?

Thank you very much.

Hello Again

In an effort to determine if the battery firmware version could be the issue I have also done this;

I attached the drone directly to my Mac laptop via mini USB and started DJI Assistant 2 version 1.2.3. Upon recognition of the aircraft, I selected refresh firmware v 01.04.0300 that is currently installed. Upon the refresh completion, I shut down the aircraft and replaced the battery. I repeated the firmware refresh for each of the three batteries I own, hoping that the battery's firmware would be updated in the process. I have also refreshed the firmware on the controller in the same manner.

I have attempted to charge the batteries as Landbo suggested and I have two batteries flashing their second light twice in repetition. They still show as "Battery Err" in the controller and DJI Go app.

I am so despondent. Last year's flying was marred by a faulty cable (the thin flat one that connected to the lightning port on the iPhone). Once that was discovered as the culprit, there was no time left to fly. That's why I am disappointed with this battery issue. You will see that this battery has only been recharged 13 times and the other failed battery, 11. I have them numbered and I cycle the batteries evenly.

R_Adams Posted at 2018-4-23 13:05
Thank you very much for your suggestion. I put both batteries back in the charger again to see if they would charge to 100% as you have suggested. After about two minutes both batteries stopped charging and have their second light flashing twice. I'll assume that the batteries are still having an issue.

May I ask how do I charge the batteries to 100%?

Hmm, it's not quite easy. If LED2 flashes twice, it means there is a cell in the battery that has overvoltage.

I have the feeling that your problems have something to do with that is not the right firmware on the batteries. Try and refresh the firmware for each battery in DJI Assistant 2.

100% is when the battery has 4 LEDs that light up.

I would try to take the hub of the charger and try to fill each battery separately. Try discharging the batteries to 20% before filling them again.

Remember, you have 180 days warranty on your batteries from DJI.

I can not think of more solutions right now. Hope you find a solution.

Regards Leif.

R_Adams Posted at 2018-4-23 11:17
Hello Again

So while I was waiting to see if someone could help me, I placed the battery with the error in the Mavic Pro and let it run until the battery showed just one light flashing. I removed it from the Mavic Pro and placed it in the charger. I have read that one suggestion is to cycle the battery (discharge/recharge). When finished charging, there was just the top light flashing two times, I imagine it was warning of an error.

Adams, if you flash the firmware of the battery and have the same error message, please contact our support and start a case: http://www.dji.com/support Thanks for your support.

DJI Elektra Posted at 2018-4-28 20:24
Adams, if you flash the firmware of the battery and have the same error message, please contact our support and start a case: http://www.dji.com/support Thanks for your support.

Thank you for your suggestion. How do I flash the firmware of the battery? I have refreshed the firmware of the aircraft with each of the failing batteries instaled; I don't know how to do anything specifically to the batteries alone. Would there be a video on how to accomplish this task?

Landbo Posted at 2018-4-23 13:57
Hmm, it's not quite easy. If LED2 flashes twice, it means there is a cell in the battery that has overvoltage.

I have the feeling that your problems have something to do with that is not the right firmware on the batteries. Try and refresh the firmware for each battery in DJI Assistant 2.

Thank you for your suggestions.

When I place the batteries in the charger, it charges until it stops. Once the charging is complete the LEDs flash an error code mentioned above. If I remove the battery and then place it back into the charger, no more charging takes place and the error code persists. I don't know how to get each cell to charge to 100% evenly.

I have tried leaving each battery rest for 24 hours after discharging to see if the cells will equalise prior to charging but so far that has not changed the outcome after charging; I still get the errors.

Thank you for your suggestions. I have had so little time in the air, I am getting really despondent over this aircraft.

It’s dead, Jim.

R_Adams Posted at 2018-4-29 05:22
Thank you for your suggestion. How do I flash the firmware of the battery? I have refreshed the firmware of the aircraft with each of the failing batteries instaled; I don't know how to do anything specifically to the batteries alone. Would there be a video on how to accomplish this task?

First, you are to be commended for your comprehensive documentation/description of the problem, and your detailed steps trying to resolve them.  Oh so often, on this forum, a poster simply whines that 'his battery is crap' and wants DJI to replace the aircraft and the box it came in !!! Thanks for the details.

That said :-) .... Follow DJI Electra's advice and start a case.  
The two times I've had issues I received satisfactory resolution.  Because you have had many reasonable attempts to resolve on your own, I think you should start with a live "CHAT" session.  In preparation I would type up a brief summary, short sentences, maybe bullet points.  When you open the Chat, start by saying you have batteries with approx 15 charges that give a two-LED err code.  Wait for their reply, and on your second response, insert the whole summary.  Be prepared to wait as it is likely that the respondent will have to check around.  If she/he doesn't have an answer, you'll be send a CASE number.  

FWIW, I would always file for a Case Number if, after a few attempts to analyze on my own a problem wasn't resolved.  Saves time and may get you directly to the point.

R_Adams Posted at 2018-4-29 05:34
Thank you for your suggestions.

When I place the batteries in the charger, it charges until it stops. Once the charging is complete the LEDs flash an error code mentioned above. If I remove the battery and then place it back into the charger, no more charging takes place and the error code persists. I don't know how to get each cell to charge to 100% evenly.

Thank you, I also see your batteries as a warranty case.

Regards Leif.

WebParrot Posted at 2018-4-29 06:19
First, you are to be commended for your comprehensive documentation/description of the problem, and your detailed steps trying to resolve them.  Oh so often, on this forum, a poster simply whines that 'his battery is crap' and wants DJI to replace the aircraft and the box it came in !!! Thanks for the details.

That said :-) .... Follow DJI Electra's advice and start a case.  

Thank you very much for your reply.

I recognise that with sophisticated systems, the devil is in the details. While DJI tries to make products that the consumer can use easily, it is a different approach that is required when trying to solve issues that come up. I have read many similar battery issues posted in this forum and tried solutions presented to others to see if they were applicable to my situation. I chose to post when I continued to have a problem after trying multiple actions. By documenting these in my post, I was hoping to drill down on other possible solutions. I was actually hoping that a DJI representative would have one more suggestion after I eliminated most of the standard responses. DJI Electra has yet to respond with a description on how I flash the batteries themselves.
I thank you for your suggestion on how to approach DJI. I will be starting a case file with support. As you suggested, I am documenting all of my efforts to date and organizing my screenshots for each malfunctioning battery and adding a thorough timeline describing my efforts to rectify the errors.

Knowing that this aircraft can cause considerable damage or injury if it should malfunction in flight, I have purchased two new batteries to continue flying while I work with DJI on the malfunctioning batteries. It is interesting that the new batteries were received with little to no energy stored in the cells. I wanted to document the new batteries prior to the first charge to have a record of how they were received brand new. It is interesting the one battery had 2% energy and just enough to allow me to capture some screenshots, while the aircraft would not start with the other brand new battery.

I have read that we are never to allow our batteries to get that low and others have recommended taking the batteries to 2%  before charging. I am confused because my failing batteries were stored after being charged to 100% and the expectation was they would auto drain to 50% after 10 days. They certainly had more energy than the new batteries that were purchased and I am worried about how to store batteries for an extended period so that I will not have this issue again.

Lastly, I hope that anyone reading this post will have a better chance of restoring failed batteries because many of the techniques have been described here. Should anyone wish to add another suggestion, I am all ears.

Have a great day, Rick.

one or more cell dammage ...same at mine ...noone solve the problem from DJI...

Battery Issue Update

I have filed a support request with DJI and they have responded. While they are sorry I have had an unsatisfactory experience, they will not help me because my failed batteries are out of warranty. Here is the response from DJI;

“Jhenirose (Support)
May 3, 07:38 CST

Hi Richard,

Good day.

Thank you for reaching DJI Technical Support.

We are very sorry for the experience that caused you on this. This is not the right experience that we want to provide to our customers. We will do our best to assist you.

We do appreciate your effort in having the troubleshooting steps conducted in your battery however we do apologize for the inconvenience; the information provided indicates that the batteries are outside of the warranty period (6 months).

Because of the structure of battery, it cannot be repaired. If it is out of warranty and indeed dead, we will just replace it with a new one by charging you as the price of a new battery. If so, we don't suggest you send them back. You can buy a new battery from an authorized DJI dealer or the DJI Online Store.

Thank you for your kind understanding.

You will receive an email survey two days after this email if not responded.
If you happen to be away and won’t be able to answer this email timely, please disregard the survey and reply to us directly.

Best regards,
Jhenirose”

I will affirm that I understood that the batteries were purchased beyond the six-month warranty period, but they were used for less than four months before stored for the winter. I have demonstrated that they have only been cycled 10 and 13 times and therefore I had hoped that DJI would wonder why their product failed after so little use. This is not the case and they have reinforced their warranty limitations.

So what did I do wrong? The manual that ships with new batteries states;

“Usage – Visit http://www.dji.com to learn more about how to use this product.”

I have been to this site and there is very little information about Mavic Pro batteries beyond how to place them into the charging hub or charger. There is a video on “Safety tips-Intelligent Battery Use and Maintenance”, however it fails as evidenced by this screenshot;

Screenshot

I am probably not the only person that does not fly their UAS in the winter and have batteries that are stored for four or more months. I checked the FAQ-Frequently Asked Questions for answers on long-term storage of Mavic Pro batteries and there are none.

So what have I learned from this experience?

1. Do not own more batteries than you need to fly between charging opportunities.

2. Fly warrantied batteries before batteries out of warranty.

3. The next time I charge a battery that has been stored for a long time; I will try charging it incrementally. By this I mean, I will charge the battery in stages, unplugging/resting it after the second and third light, before fully charging to the fourth light. This is based on the anecdotal evidence that the two failed batteries were left in the gang charger until complete and my remaining, functioning battery was charged incrementally.

4. To answer my original question, I don’t believe that I did anything wrong. Certainly based on the available information on the DJI website.

Thank you to everyone that tried to help me with this issue, I appreciate the time taken to respond with ideas and suggestions.

R_Adams Posted at 2018-5-3 05:50
Battery Issue Update

I have filed a support request with DJI and they have responded. While they are sorry I have had an unsatisfactory experience, they will not help me because my failed batteries are out of warranty. Here is the response from DJI;

Thank you for your update. It's annoying but I do not think it's the way you've charged the last battery that made the difference. If you have fully charged the batteries before you put them in storage, they should be able to survive 4 months of inactivity and seems almost as new. Will say they have been half defective before you put them away for the winter.

I have two batteries for each of my drones. When I have flown all four, I have become tired and have to rest at least 4 battery charge time before, if and so on.   

Regards Leif.

I recently received an email from DJI with the subject; How would you rate the support you received?
I will post my reply here as part of my experience during this battery failure.

"I purchased my Mavic Pro based on the recommendations of friends. They felt it was well designed and flying would be relatively easy and trouble-free.

I would only agree if all the components worked as designed, however, that has not been my experience. Within months of purchase, the RC cable that connects the iPhone to the RC would intermittently fail during flight rendering me “blind” without video feed from the aircraft.

I lost valuable flight time trying to track the cause of the problem. Once rectified, winter had arrived in Canada. Knowing the batteries would be subjected to less than 5°C, their lower limits, I put my aircraft away until conditions improved.

This contact with your support department came as the result of my relatively unused batteries failing after being charged and after exhausting unsuccessful searches of your site for information on how to correct this problem.

I purchased DJI Care and it was still in effect when I contacted your support department. My expectation was that these failed batteries should have been covered under that plan. It was not clear to me that DJI Care would only cover some things for one year and others for only six months. Humorously, I recently received an email from DJI suggesting I extend my DJI Care plan. Since this plan will not cover all the aircraft systems entirely, I will not be extending my coverage and I regret that I purchased it in the first place.

Am I happy with the response that I received from your support department? I think you can see that I am not! Failure to apply my DJI Care to this issue is a choice you made as a company and in the future, I will make better-informed choices as a consumer."