DJI TB47S Battery Cell Deviation

One of the cells in the TB47S battery is showing slightly lower voltage than the other 5 cells. Aircraft refused to take off.
Any advice on best way to deep cycle?

I have a Smart Powercharge that does this but have done it by hovering about a foot of the ground on the I1, both useless to you I know but I’m sure you can buy a lead with a bulb for the I1 for this purpose, are the connections the same on the I2?

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They don’t have any though, perhaps you could make something.

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Smart Powercharge, that sounds perfect, could do with one of those.
I thought about a bulb and making a discharge lead, but at 22.4v and 4500mAh I presume I would need to use a 24v bulb and it would take quite a while to run battery down.
Might start looking to invest in a Smart charger that can deep cycle the batteries.
Appreciate you taking the time to help out

I seem to recall that a 120watt 12/24volt Halogen bulb was used on the early Phantom 2’s as a discharge method?.
Come on brain!, where have I seen it !.

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are not most lorry bulbs 24 volt?.

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Thanks Chris, yes I think a lot of commercial vehicles use 24v bulbs, just not sure how long it will take to discharge down to 5% from almost full. I was trying to think of something that would work quicker than a bulb :bulb:

A bank of 5 x 20 watt wire wound load resistors?.
But, you would need some sort of control circuit?

Bloody hell Chris, you’ve lost me now.
I think I will buy the largest 24v bulb and 2 bits of wire, keep it simple ha ha

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“Well Cuntstable, I was walkin’ down this street in Halifax, and there was a Bright Light, a flash and a Bang, and this bloke came through the windows arse over tit !!” !:laughing::laughing::laughing:


Wouldn’t be the first time!

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Get 2 x 12volt Halogen Bulbs, will do the same, but ,quicker ! (wired in series)

Yeah, I could manage that, will try it in the morning.
Thanks Chris

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OK, thanks for all the advice.
Managed to use a 70w 24v bulb and connected it direct to battery with the low cell, discharged until battery turned itself off.
Put the battery back on charge and cell is now showing no deviation from others, fingers crossed it doesn’t reappear over time.

Appreciate the help.


great news Mick !

Appreciate your help Chris.
Advice from DJI Support was buy a new battery :battery:.

Yeah, they would !

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