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How Is The Capacity For A TB4x Battery Calculated?

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Bought a Used Battery
I fully Discharge the Battery til it Shuts Off
I fully ReCharge the Battery til Charger Shuts Off

When I use the LED's to Check Capacity
All four light up

When I use the Go App, the Fresh Capacity is roughly half of the Capacity. Ex: TB47 2567 / 4500. 57%

How, do the battery Internals Calculate that Number?

It appears it is based on the total of the cells voltage compared to the max voltage it can attain.
 
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Bought a Used Battery
I fully Discharge the Battery til it Shuts Off
I fully ReCharge the Battery til Charger Shuts Off

When I use the LED's to Check Capacity
All four light up

When I use the Go App, the Fresh Capacity is roughly half of the Capacity. Ex: TB47 2567 / 4500. 57%

How, do the battery Internals Calculate that Number?
You only have 2567mah out of the original 4500mah left to fly your drone. If you want to use that battery Inwould test fly it very close to the ground. Low capacity batteries have a tendency to cut out entirely when close to 30% capacity. The drone will drop from the sky.
 
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You only have 2567mah out of the original 4500mah left to fly your drone. If you want to use that battery Inwould test fly it very close to the ground. Low capacity batteries have a tendency to cut out entirely when close to 30% capacity. The drone will drop from the sky.
Thanks for your help.

What I am looking for, is -how- the 'Capacity' of that battery is -calculated-. It has to be based on Battery Voltage and other factors. Why do all the 4 Leds glow green, when half the capacity is left? These two are the only indicators as to how much power is left. ALso, the indicator(s) on the Main Panel. That's my question.
 
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damoncooper said:
I had 5700 when new! Now down to 5136! That's 564 missing mah!

Where is my mah??

View attachment 5908
All lipos will loose their capacity over time. As the pack ages its internal resistance increases and its ability to convert chemical reaction to power diminishes. What the DJI calibration procedure does is to take into account the aging of the cells and calculates how over time the pack capacity reduces.
They have written the algorithms to take into account not only times, charged/recharged but also to what level of depletion the pack has been drawn down to and generally how it has been treated.
Having said that, their algorithms do seem a little 'over zealous' in how they go about calculating loss of capacity!
Of course, this would have absolutely nothing to do with wanting to sell more batteries. :rolleyes:
I found this post on this forum. Does it help?
Best
 
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All lipos will loose their capacity over time. As the pack ages its internal resistance increases and its ability to convert chemical reaction to power diminishes. What the DJI calibration procedure does is to take into account the aging of the cells and calculates how over time the pack capacity reduces.
They have written the algorithms to take into account not only times, charged/recharged but also to what level of depletion the pack has been drawn down to and generally how it has been treated.
Having said that, their algorithms do seem a little 'over zealous' in how they go about calculating loss of capacity!
Of course, this would have absolutely nothing to do with wanting to sell more batteries. :rolleyes:
I found this post on this forum. Does it help?
Best
Thank you!

Thats about what I thought. There has to be several factors. How many times it has been charged is on eindication but, most are probably just topping off charges. Then cell voltage is another indicator. One thing I have not seen is total time in hours/minutes the battery has been in flight.

To me, the true Capacity is how long at a steday current draw will the battery provide enough power (volts and amps) to power the drone. Or, as my wife says, 'My Toy Helicopter'.

I am surprised how a battery 5-6 years old and dormant can still be useful. I do not think NiCads could do that. Now Lithium Ion.

Thank you ...
 
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Thank you!

Thats about what I thought. There has to be several factors. How many times it has been charged is on eindication but, most are probably just topping off charges. Then cell voltage is another indicator. One thing I have not seen is total time in hours/minutes the battery has been in flight.

To me, the true Capacity is how long at a steday current draw will the battery provide enough power (volts and amps) to power the drone. Or, as my wife says, 'My Toy Helicopter'.

I am surprised how a battery 5-6 years old and dormant can still be useful. I do not think NiCads could do that. Now Lithium Ion.

Thank you ...
In case you are looking to refresh your I1 batteries I recently ordered fresh lithium from these guys: 73.87US $ 11% OFF|Top Brand 100% New 4800~6000mAh Battery for DJI Inspire 1 TB48 TB47 Intelligent Flight Batteries + free tools|Drone Batterys| - AliExpress

It hasn't arrived yet but I've heard success stories and Im really looking forward to having a truly new battery once its swapped, might be worth a shot if your comfortable soldering, other wise there is always the boys at heliengadin: REGENERATED TB48 battery for DJI Inspire 1

I'm spreading this info around cause I don't want to see the I1 platform fall by the wayside as its such a capable aircraft and the more people buy aftermarket the longer they'll produce the stuff, in theory anyway XD.
 

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