Battery Re-Calibration

[Quadpilot]

All this for 1 minute of flight time! Seems like a true waste of time and effort. Just change batteries and move on.

This re-calibration is a one-time action following update to FW 1.3.0.00. This update provided for a different battery calibration algorithm that would allow for the batteries to be reset to factory specs for a full charge (i.e., 4500mAH for TB 47 and 5700 mAH for TB 48). If not accomplished, your batteries will most likely show less than those values after charge to 100%.

But it's your choice.

 

[Adamastor]

This re-calibration is a one-time action following update to FW 1.3.0.00. This update provided for a different battery calibration algorithm that would allow for the batteries to be reset to factory specs for a full charge (i.e., 4500mAH for TB 47 and 5700 mAH for TB 48). If not accomplished, your batteries will most likely show less than those values after charge to 100%.

But it's your choice.

Ditto

 

[Ward Paterson]

I fly to 10% and land, then make sure my controllers need a charge, and use the Lipo to Controller lead and charge the controllers until the batteries will no longer turn on ... So far so good using this method. Seems to completely drain the TB batteries

 

[The Phantom Menace]

I fly to 10% and land, then make sure my controllers need a charge, and use the Lipo to Controller lead and charge the controllers until the batteries will no longer turn on ... So far so good using this method. Seems to completely drain the TB batteries

WP...I like your method. This worked for me with both of my batteries.
Thanks.

 

[Ibflyen]

From what I (thought) I knew about lipos is that if they are getting that hot and cells are being damaged in the process then it means they are being discharged too far.

 

[Ward Paterson]

From what I (thought) I knew about lipos is that if they are getting that hot and cells are being damaged in the process then it means they are being discharged too far.

The Inspire batteries are unlike any standard lipo you would buy from Hobbyking, or elsewhere.. They are like mobile phone batteries. They drain to a set lowest voltage then power off preserving themselves. They have very sophisticated protection mechanisms and they self power off when at the lowest safe voltage..

 

[Ibflyen]

The Inspire batteries are unlike any standard lipo you would buy from Hobbyking, or elsewhere.. They are like mobile phone batteries. They drain to a set lowest voltage then power off preserving themselves. They have very sophisticated protection mechanisms and they self power off when at the lowest safe voltage..

Maybe that "set lowest voltage" is too low if everyone is seeing very hot batteries and a loss in overall battery life after doing this recalibration procedure. I realise this would mean DJI has it set wrong so please forgive my ignorance of these smart batteries.

 

[m00se]

The battery will get very hot. A couple of mine reached 56 deg C, which is higher than DJI specifies for battery operating temp, but it didn't seem to harm them. Cooling them with A/C will help. The measure of whether it worked is that after a full charge the capacity should reflect the full rated value, as posted above by @Scotflieger.

Ive had one hit over 70c....... flying with a 700g additional payload in approx 45 - 50c ambient temp.......
Needless to say I havent done that again, and after some advice from others, I precool the batteries with the cars AC to try and help them stay cool a little longer, I also now land at around 40% to try and not cook them..... I would rather fly less time but get more flights before a cell goes bad than push each flight and have a bad cell in a short amount of flights.

 

[m00se]

Maybe that "set lowest voltage" is too low if everyone is seeing very hot batteries and a loss in overall battery life after doing this recalibration procedure. I realise this would mean DJI has it set wrong so please forgive my ignorance of these smart batteries.

Normally a hot battery is a sign of it being discharged at close to or more than its max C discharge rating.
There is a tradeoff in battery chemistry between capacity and discharge ability, if you get the threshold right then you can get longer flight times, i suspect they have tried to get it right.
Also their cells charge up to 4.4v per cell, not 4.2, suggesting there is a difference there.
And within the pack, there are metal plates which help draw the heat to the outside of the pack, so it would be fair to assume that the outside feels hotter than on a normal pack due to this.

 

[Scotflieger]

Ive had one hit over 70c....... flying with a 700g additional payload in approx 45 - 50c ambient temp.......

M00se, please tell where do you live (no survive) to have such obscene temperatures? And they say there is no global warning....

 

[LockMD]

I fly to 10% and land, then make sure my controllers need a charge, and use the Lipo to Controller lead and charge the controllers until the batteries will no longer turn on ... So far so good using this method. Seems to completely drain the TB batteries

WP...I like your method. This worked for me with both of my batteries.
Thanks.

I like this method too, BUT I thought for it to recalibrate the batts it has to be a continuous drain ???

 

[Scotflieger]

I like this method too, BUT I thought for it to recalibrate the batts it has to be a continuous drain ???

Correct. The CONTINUOUS discharge 100%-5% is required this once but not for 10-20 charge deep cycle.

 

[LockMD]

Correct. The CONTINUOUS discharge 100%-5% is required this once but not for 10-20 charge deep cycle.

Gotcha, thank you.

 

[Pronevitch]

There seems to be a lot of confusion about re-calibrating batteries with the release notes of FW 1.3.0 stating to take batteries down to 5% then fully charging back to 100% to bring batteries back up to full capacity (4500mAH for a TB47). In my experience, 5% does not work, since after doing 5 TB47s that way with FW 1.3.0 I saw anywhere from 4100-4400 mAH capacity after charging them back to full.

So I did some research and found a post by @mixmaven on RCGroups Inspire thread here who stated that he found out from a DJI battery expert that the trick is to get the lowest cell voltage down to 3.30V, which in my case meant bringing the batteries to 0% (This has been confirmed by RCGroups DJI Forum Support @blade strike). Even then, once my motors stopped, lowest voltage climbed to around 3.40-3.45V before the voltage drained to 3.30V.

Easiest way I found to do this: Fly a fully charged battery down to around 20% (turn your battery warnings down to 15% and 10% respectively), then hover just above ground with LG down and wait for the RTH message, cancel it, and when you get the critical battery warning at 10% and the craft wants to land, just hold the throttle up to hover until it shows 3.3V (probably lower than 5% showing) and let it land. Once the motors stop, the cells will probably increase about .10V, so just leave it powered on until you see 3.30V on the lowest cell. Be mindful of battery temp while doing this, it did climb pretty high in this procedure. If in the field and once the motors stop, take off the props and put Inspire in front of the A/C vents in your vehicle. The trick, once again, is to discharge in one cycle down to the desired voltage, leaving the battery on the whole time.

That worked for me. Upon recharge to full, all my batteries showed a full 4500 mAH capacity. As mentioned elsewhere, battery life will probably drop a couple percentage points from previous value after the calibration. Since calibration, my impression is that I've gained about a minute or so in flight time on my batteries.

Don't forget to reset your battery warning levels once you go fly again!

I discharged my inspire 1 battery down to 1 % I then soaked in ice water to cool it now it doesn't work at all? Thanks for the bad advice!!!

 

[Kilrah]

LOL.

 

[Ward Paterson]

I discharged my inspire 1 battery down to 1 % I then soaked in ice water to cool it now it doesn't work at all? Thanks for the bad advice!!!

Hmmmm.. Soaking in ice water is not really the right thing to do......

 

[Ward Paterson]

The DJI Manual states for these battery cals, to drain the battery until the battery does not power on.
I still maintain fly till 10%, then just charge your hand controller until the battery turns off, then fully charge again to complete the cal

 

[Yardman]

Don't know if it has been said already, but I have also noticed that the recharge counter is reset to 1 after discharging below 5%.

 

[AMCR]

I was getting a warning stating that my batteries needed to be discharged to 5% then recharged. I flew until 10%, landed and left the copter on until 3%, powered down and recharged and still have the same warning. I have done this 2x per battery now and still getting the warning ??? any advice on this. Thanks in advance

 

[The Editor]

I was getting a warning stating that my batteries needed to be discharged to 5% then recharged. I flew until 10%, landed and left the copter on until 3%, powered down and recharged and still have the same warning. I have done this 2x per battery now and still getting the warning ??? any advice on this. Thanks in advance

This has been covered a few times already - you need to take your batteries down to 3.3v per cell which can be below 5 or even 3% depending on how they are calibrated currently.
Basically, run them down until they turn off and cannot be turned on.
Then allow the packs to cool, then fully recharge them.