TB48 - disaster time

ChrisRL · Nov 12, 2016

The Editor said:
And you would trust the chemistry in a pack who's cells had been dragged down below LVC plateau to hold up and be reliable in keeping a 3kg machine airborne while drawing 5C in climb-outs?
Don't fly anywhere near me with those batteries installed!

Editor, it would depend on if I knew how the batteries dropped below LVC. Most of them just aren't being exercised or have already sat in a factory, etc., but those would still be in warranty. However, if one did buy a 47 or 48 or two, fly a couple charges off it, then forget to charge it, then that would be a case for giving it a go and seeing if it might work properly again. Agreed, mishandled or fried batteries aren't worth it, but as I mentioned in my notes above, I'd be testing them awhile (at least through two or three charge cycles) before I put them in anything that flew.
Best
Chris

The Editor · Nov 12, 2016

ChrisRL said:
Editor, it would depend on if I knew how the batteries dropped below LVC. Most of them just aren't being exercised or have already sat in a factory, etc., but those would still be in warranty. However, if one did buy a 47 or 48 or two, fly a couple charges off it, then forget to charge it, then that would be a case for giving it a go and seeing if it might work properly again. Agreed, mishandled or fried batteries aren't worth it, but as I mentioned in my notes above, I'd be testing them awhile (at least through two or three charge cycles) before I put them in anything that flew.
Best
Chris

Fair enough.
(I still don't want you flying over the top of me though )

ajohnsonlaird · Nov 12, 2016

Rich Sugden MD said:
You remove the white top by wedging a screwdrive in each end, dislodging the 'tabs', while pulling out on the sides, as there are clips there too ... Then disconnect the small plug w. wires going to each cell bank ... small black wires .. slide the connector out sideways carefully ... it DOES NOT pull straight up ... pull it out sideways. Leave it unplugged an hour, plug it back in and see if it charges. If there was sufficient charge remaining in the battery it will charge .. but if you discharge LiPo's below a certain threshold they are destroyed.

Tried this on my three bricked batteries due to DJI design that drains them to destruction during storage and no luck.

None of the four DJI-Paperweights responded to this technique, I'm afraid. The "Intelligent" battery controller firmware is smart enough to discharge the cells to zero volts.

Andy.

William Gaddy · Nov 13, 2016

That has to be the funniest thing I've read o

Mad_angler1 said:
I know I struggle to comprehend this part

So the Op bought used Batteries with completely unknown history then complains that DJI don't supply parts for something that's a massive fire hazard and requires specialist tools and training to repair.

Sorry but wow.

Now where do I complain that I can't buy individual pixels for my TV ?

I'm sorry, but that has to be the snarkiest and funniest response I've read all week. Gold Star, sir.

Cheers

Mad_angler1 · Nov 13, 2016

William Gaddy said:
That has to be the funniest thing I've read o

I'm sorry, but that has to be the snarkiest and funniest response I've read all week. Gold Star, sir.

Cheers

Thanks [emoji3]

Yea sorry OP was not in a good mood when I posted that, I don't tend to let the Mad part of Angler out much.

Batteryman1952 · Dec 1, 2016

jaymiejame said:
high chris i work down to component level as well, repaired 2 batteries of my own another two ive got coming in the post this week, to source the cells i'll take them from a battery that has a faulty circuit board and the cell are fine as you can see from the images i have tb47's and tb 48's cells its no great sweat changing the cells. if you disconnect the cell voltage reading connector the wide white one then charge the battery with a balance charger, start off at a low voltage about 14v and build up to 22v. then reconnect the cell voltage reading connector and charge normally with dji charger. once its full up put it in the inspire and press the battery voltage indicator it'll tell you which cells are faulty i swap the pair out.some people think there's magic involved in mass producing stuff in factories, they use the same cells, soldering irons and pair of hands etc ,that i can provide myself and i'm sure you can also. it can be done i've done it so have others.i'd rather pay £25 quid for a tb48 than £189 and do an hours work, if it fails it fails. the circuit board will test the battery and tell you if the cells are faulty, thats it's job. good luck. and if you can source the new cells please send me a link.

Gentleman
I realize that technically you can replace cells in your battery but this is dangerous. Please watch a couple videos on my website to see how these cells may explode. Remember that even if the cells don't flame, the vapors are flammable AND poisonous. See www.Planegard.com

emtea · Dec 6, 2016

Batteryman1952 said:
Gentleman
I realize that technically you can replace cells in your battery but this is dangerous. Please watch a couple videos on my website to see how these cells may explode. Remember that even if the cells don't flame, the vapors are flammable AND poisonous. See www.Planegard.com

I'll echo Batteryman's comment. I also feel the pain of how DJI did the batteries but, from a liability point of view, they are smart in saying you need to replace the whole thing. The way I see it, I consider the batteries as an entirely consumable part of the drone, including the board, etc...if my cells go bad, you can be sure I am recycling the entire thing and just buying a new one. For $150 or so, I can get a fresh new warrantied battery. I know there are cells you can replace into the battery and they are fairly cheap but, once I factor in the time, the effort, the pain, and the risk of blowing up my face, the $150 seems like a good deal to me.

jaymiejame · Dec 10, 2016

ChrisRL said:
Will do, Andy, and thanks!
Yeah, if we can source properly and get maybe the OEM people to supply us, I'll be trying for a group buy if the prices are right and dji doesn't cut the prices to ridiculous levels.
I'm going to do the same thing - i.e. I have a battery with bulged cells and good board, and another with what appear to be good cells and definitely a bad board, so that's the first place I'm going to go, like you.
All the best and let's keep each other in the loop, especially after the 15th. I'm very interested to see what dji comes up with!
Chris

well from what i've figure out today, the cells are all charged together right, so if one pair is slightly higher than the rest, the circuit shoves out an error,ok so lets calibrate..nono. when you discharge the cells they still discharge at the same rate so one pair is still higher, so recharge you'd think it's a balance charger circuit...no it isnt when you recharge it charges at the same rate so one pair is still higher.so it still spits out an error. what i thought was a balance circuit just monitors the voltage it doesn't balance,so to get around it i fully charge each cell,individually, now its balanced.it'll now charge and discharge equally. thats why they have so many duds, if the cell is different to the rest,its spits out an error and discharges down to zero, thats why they have so many duds.

TB48 - disaster time

Similar threads

Privacy & Transparency

Privacy & Transparency