Hi.

I have an Inspire 1 with four batteries (two TB-47 and two TB-48).  The manual for the drone says clearly that a feature of the Inteligent Flight Batteries is "Over charge Protection: Charging automatically stops when the battery is fully charged."

It turns out that they do NOT have effective overcharge protection.  I left all four batteries on the hub and they self-destructed.  I would not normally leave simple LiPos on a dumb charger, but (i) the charging logic is inside the batteries and is supposed to be sopisticated and (ii) I was called out of town unexpectedly and just forgot about the batteries, to be honest.

After several back and forth exchanges with DJI support, they think they known what happened and they tell me I am out of luck.  That's $700 of batteries that are destroyed.  They don't turn on at all (no lights come on).  I have read about people taking batteries apart and reviving them but I don't feel I should have to do that and I also don't want to be accused of voiding the warranty (even though they won't honor it).

The root cause seems to be a design flaw / bug in the firmware of the batteries' charging logic.  The normal behavior is, indeed, to stop charging when full.  But, if still plugged in (perhaps this is Hub-only behavior-- not sure), then the auto-discharge feature on the batteries ends up restarting the charge cycle.  This somehow leads to a death spiral.  I note that the "death" of the battery is at the electronic level, not the chemical/actual battery level.  It is NOT that the batteries won't hold a charge or that the exploded (although one of the TB-48s is swollen).  Instead the electronic logic board is fried and/or hung/unresponsive.

A more sensible approach, which I assume they will implement in the future, would be to tweak the logic such that: "If my button has not been pressed since the last time I completed a charge, do not start another charge cycle."  This would seemingly allow for fully safe and predictable behavior.

These batteries are expensive and sophisticated devices with on-board processors and charging circuitry.  It is 2015.  Any suggestion that self-destruction is normal/intended bahavior after leaving device plugged-in is outrageous.  Especially when the root cause is poorly written software that fails to address a fairly foreseeable use case (customer leaves device plugged in for a long time).

DJI support says it is the "best practice" to not leave things plugged in.  Sorry, but failure to observe best practices should not be an excuse to fry $700 worth of gear---ESPECIALLY when the manual claims that batteries are "intelligent" and feature "over charge protection."

Any advice as to what I should do here?

Small claims court. Bring all DJI documentation stating that there is overcharge protection. I bet you win.

remltr Posted at 2015-12-9 17:18
Small claims court. Bring all DJI documentation stating that there is overcharge protection. I bet y ...

Im sure he will win but the lawyer going to charge a grand. Thats why these companies dont care about small claims like this.

You dont really need a lawyer for small claims, that is why its called small claims.

cnicholson, did you use a DJI charger or a 3rd party charger?

If you  did use a DJI Charger, I would PM one of the representatives here and ask for their help. DJI-Tim or Tahoe_Ed, DJI-Malcovich  etc.

If there lies no help, then you can take legal action or any action you choose in doing so.

@teamnest1: I used DJI power adapter and charging hub.  All DJI stuff.  

Thanks for point to DJI reps.  I will PM them.

Ugh.  So how do I PM people?  Sorry to be a noob on forum functionality.

Hi cnicholson!Sorry for your experience!  I would like to  help you out with this case!
Few questions here: For how long did you leave your batteries on a charge?
What the firmware version are you using on your hub?
Could you please leave us your contacts so we can solve this together
Thank you!

DJI-Tim Posted at 2015-12-10 07:25
Hi cnicholson!Sorry for your experience!  I would like to  help you out with this case!
Few question ...

Hi  Tim   Ive just purchased a DJI charging hub and a 180w charger,  Are there any limits to its use I should consider so I can avoid this problem!!!

I take it is the FW version of the batteries your talking about not the FW version of the hub itself?

drone vision Posted at 2015-12-10 16:35
Hi  Tim   Ive just purchased a DJI charging hub and a 180w charger,  Are there any limits to its u ...

I'm talking about the hub itself

drone vision Posted at 2015-12-10 16:35
Hi  Tim   Ive just purchased a DJI charging hub and a 180w charger,  Are there any limits to its u ...

Don't leave your batteries on a charge for too long, after they are fully charged

DJI-Tim Posted at 2015-12-10 09:24
I'm talking about the hub itself

How do I check the Hub FW version?

teamnest1 Posted at 2015-12-9 21:24
You dont really need a lawyer for small claims, that is why its called small claims.

cnicholson, di ...

Try going to small claims court without a lawyer, the big company lawyers will be, let me know how you make out, lol!!!!

Note to self ...
Buy a "timer" for the wall outlet where I charge my DJI batteries ... to avoid this!

DJI-Tim Posted at 2015-12-9 23:25
Hi cnicholson!Sorry for your experience!  I would like to  help you out with this case!
Few question ...

It must have been a couple of weeks on the charger--- long enough for the auto discharge to kick in, which I think was the root cause / software bug that made things go bad.

I do not know the firmware version of the Hub (I bought it very soon after release).  Firmware on batteries would have been current.  I am out of town now, but will try to figure out early next week.

you can reach me at cnicholson (at sign) iname.com

I think this is a classic case of a failure of quality control at the system integration level.  Each component was designed/tested and 100% functional in isolation, but the interaction among the components (as deployed in the filed) caused a failure.  The battery is where the brains are, so the battery would be smart enough to guard against this scenario.  Neither the charger nor the hub can "force" a charge--- the battery has to initiate it.

And a simple logic tweak (I offered to fix the source code for free) would eliminate the issue ("Do not initiate another charge session if button has NOT been pressed since starting an auto-discharge cycle." ).  You could get fancy and have a special blink pattern to alert the human that the charge is NOT starting, but the intuitive and natural thing would be for the human to be curious, press the button (overriding this safety) and then see the charge start.

Thank you.

Richardrambone Posted at 2015-12-10 05:10
Try going to small claims court without a lawyer, the big company lawyers will be, let me know how ...

I'm actually a lawyer, so I feel pretty comfortable about going to small claims court and winning-- even though it will cost me MUCH more than $700 in lost time and expenses.  Still would be worth it to me on a cosmic level.

I just hope I don't need to go that far.  I bought some of this stuff via Amazon and on credit cards with strong consumer protections.  So I have some other options.

I'm sure I'll prevail eventually....just trying to do so with minimum hassle and also maintaining civility.
Frankly, I was hoping to resolve this provately with DJI support, but failed at that after several email excahnges, which I can post at some point if necessary.  


Anyway, DJI-Tim has reached out (see above), so hopefully he will help me resolve this.

At least it sounds like tha ball is rolling on this. I hope it all works out in the end! Keep us updated.

Richardrambone,
yes, even if they have a lawyer, doesn't mean you will lose or that the judge will not hear your case. I've been in that situation and most of the time, you come up with an agreement before you see the judge. Whether you going up against a small company or Walmart, you always need to stand up for yourself.

I had an identical experience with the same setup (I had 3 TB48s and 1 TB47).  Support originally indiciated they would replace everything, but after 2 weeks came back and said they will not honor the warranty: "Because these damages were incurred due to improper, unsafe charging practices, we would not be able to replace these batteries for you under the warranty. This would require for you to purchase replacements on your own. We appreciate your understanding."

What's the point of overpriced, intelligent batteries and and overpriced, intelligent multicharger if the solution isn't actually intelligent?

Ticket #217138, should anyone affiliate with DJI wish to investigate further.

-jd

Lawyers acting as lawyers are not allowed in small claims court. It is just the litigants and the judge. Like you might see on Judge Judy, but hopefully with a little more decorum.

Richardrambone Posted at 2015-12-10 08:43
Im sure he will win but the lawyer going to charge a grand. Thats why these companies dont care ab ...

You don't need a lawyer in small claims court. Not here in our state.

Not sure but the problem MAY be due to charging 2 different battery types in the same time, different Amp capacity on a single charger. I had a similar problem some long time ago charging 2 Li-Po of different voltage and Amp capacity on the same charger and both went to battery heaven....

DJI admitted this was a bug in their firmware update to the charging hub.  I just saw it and sent you a private email.    The link below will take you to the update page - click on the .zip file for the charging hub update - and inside the .zip file is a PDF that tells you that the update fixes your exact issue.    They def need to replace your batteries.   They also need to make a Mac version of their updater app!

DJI Inspire 1 Update Page

Ryan Gordon Posted at 2015-12-21 14:13
DJI admitted this was a bug in their firmware update to the charging hub.  I just saw it and sent yo ...

Thanks.  I agree that this is an admission that they had an undetected bug that cause my problem (and presumably others).

Unfortunately, neither DJI Tim nor anyone else at DJI has followed up with me.  I'm not in the mood to go to war during the holidays, but it will be a New Year's resolution to get this resolved.

I've already been forced to buy two new batteries just to be able to fly while this waits unresolved, so I'll now expect a return/refund for those as part of the ultimate settlement, as I can't use six batteries.....

Yea good luck!! I think the issue is now pretty much solved.   The hard part to understand is that the update was released back in Sept - so all these replies from folks at DJI acting like they dont know what is going on is pretty unfortunate.

From a user standpoint, when you buy a DJI product - I think there should be some sort of registration involved....like, the hub for instance.   Its unreasonable for a customer to constantly check the DJI website for updates, and when major bugs are found (IE: yours) a mass email should go out.  Very similar to how they do safety recalls with cars.

At the end of the day, a bug in the charging system of the drone - which would result in a fairly heavy inspire falling from the sky and hitting someone's property, or worse yet, a person - all over a programming bug....is a major lawsuit in the making.  I'm sure you'd agree, being a lawyer.  It has negligence written all over it.  

The more I learn about this $6k investment I just made - the more I wish I was still in my return policy to get my money back.

So this was a problem with a firmware update on the hub.......everything I own is completely up to date, but I have not updated my hubs........maybe I should not them then.
I also have to echo that a lot of us out here use these products for video and photography........and a lot of us use Macs, so it is very upseting that firmware updates seem to be random from Mac and PC......... you really need to service both camps DJI........ you have such a great product DJI.......please dont stuff it up by bad support in these ways...ie Hub, Lightbridge etc etc....

I asked DJI support to reconsider my warranty rejection based on this thread and the firmware issues, I received this variation on 'pound sand':

"Thank you for your response. Even with the latest firmware update, leaving the batteries on the Charging Hub for a month is still an unsafe charging practice that voids the warranty of the batteries. Unfortunately, we are still unable to replace the batteries within warranty. We apologize for the inconvenience, but appreciate your understanding in this matter."

Formerly-proud owner of a DJI Inspire 1, DJI Phantom 3 Professional, and 4 dead TB48s.  Boo on you, DJI.

-jd

     I'm sorry I disagree, I would not expect DJI to cover my batteries if I left just  one  of them on a  standard charger for a month  and you had 4 of them on a Hub Charger For 2 weeks to a month.  That in itself is just dangerous.   You know these batteries cycle  and leaving them un-attended was just dangerous no matter what.  I am sorry for the loss. I wish once    someone would say once ," Wow, lesson learned wont do that again and  a  head's up to you other pilots, dont let this happen to you ". ( Which You partly did by posting the thread, this part was good )      I dont understand why it has to be , I am never buying this product ever  again , I am going to litigate etc.  A company can not stay in business if every unhappy customer  got there way.  It sucks you lost your packs but come on, common sense says not to leave batteries un-attended , they are supposed to be monitored while charging.  I do find it humorous to think of Judge Judy getting this case though......And I am truly sorry for the loss of the Battery packs.  And I do think DJI should have some type of Special Discount  Prices when customers have this type of damage, like 5% over cost or something to that effect.  That way they dont lose money and maybe keep the customer  somewhat happy.  

donnie

I guess the problem here was the fact that the batteries claimed to stop themselves, and there's no mention of time frame as to how long they will be capable of controlling themselves while plugged in?  But ya, leaving something charging for a month straight is a bit reckless. I'd be in two minds as to who is wrong in this case.

DJI-Tim Posted at 2015-12-10 17:25
Don't leave your batteries on a charge for too long, after they are fully charged

Thanks for that advice, DJI-Tim. When will DJI publish a Mac version of the charging hub FW update? The Win version was published 09/09/2015. That's a long time to wait.