Hello everybody!
I'm not a forum guy, so I was just watching here what other people say, until now. Recently I've checked batteries from my Mavic Air which I bought less than 2 years ago, at July of 2019, and found out that one of three batteries from my fly more combo is dead. At first, I thought that it will charge, but it didn't. I did my research and found out that those batteries can lock themselves to protect user from a faulty battery during the flight, which is good, BUT. Here goes the main thing: that battery was used and charged only TWICE. And it was taken care of, I was checking it from time to time and charging it according to the User Manual. Now there is no "magic" about those batteries, they all are simple LiPo cells and use Texas Instruments chips to control their parameters. And those chips were programmed to lock batteries under certain circumstances. Like (in my case) when voltage of the cells goes below given minimums. Which is also alright, sometimes LiPo batteries stop working after they've been discharged too low. And here is another BUT. I understand that what DJI guys are trying to do here is done for our protection (and to protect other people from UAV’s that's falling from the sky), but still, I don't get one thing. DJI customer service told me that I can do one of two things: either buy new battery from them, OR send my existing battery for a paid repair. Why there isn't third option (given its age and this whole situation)? By that third option I mean remote unlock. Those batteries are unlockable with special tools, like EV2300 programmer (or development board if you will). And there are actually some guys online who sell special software which is intended for people who repair batteries (not only UAV batteries but also ones from notebooks, phones, etc.) which can unlock those batteries. You can check YouTube and see that it’s actually possible.
There is a thing called PF or Permanent Failure and it's just a "flag" at IC of the battery that locks it. To turn it off you just connect your battery to PC through EV2300 (or other board that can communicate with battery) and push a few buttons. Done. Battery is working again.
Now what I'm trying to say here is that our UAV is a same programmer for our battery, it can communicate with it and it can, for instance, upgrade its firmware. More than that, PF won't activate while UAV is still in the air to prevent it from falling from the sky. It will kill the battery in a certain scenario but won't just turn off, unless there is a hardware failure. There is also a problem – those chips have a passphrase and you can’t just take any adapter connect and mess with their parameters, which is also good since that protects us from the batteries with wrong manufacturing date or wiped charge counters. DJI can’t give us a passphrase by the same reason, but I have an idea what they actually can do for us and it is a remote unlock. I understand that they can’t unlock ANY battery, in case it has some other issues, but they can run remote diagnosis using our UAV which can be connected to PC as programmer and some kind of service software, which don’t have to be in a public access, but can be sent to those who has same problem as me and activated for a small period of time while DJI specialists could disable that lock. Even if they will do it on a paid basis it will be easier, cheaper and more effective then sending our batteries to them every time that little lock thing works by itself. At the same time User Manual states that battery should prevent itself from such discharge and enter hibernation mode, not permanent lock, so that’s not exactly our fault which makes all that situation even more important. More than that while battery will be transported to DJI it will discharge even further as time goes, so at the moment it will arrive to a service facility cells can be completely dead. Which leads us to another problem which is environmental since those cells need to be recycled. So, my point is that DJI actually can take that idea into consideration since I actually can repair my battery myself, it will take some time and it won’t be easy but I have some knowledge and tools how to do that, but for those who can’t do that this situation is much more unpleasant. I will be grateful if DJI guys (or anybody else with more knowledge than me) will correct me if (and where) I might be wrong, but that’s my thoughts and my point of view on that problem, which already exists for a while. Thanks for your time. |