Wifi Extender out of batteries - motors stopped!

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It happened on the kitchen table, without props on. I wanted to drain both Wifi extender and Phantom batteries, so I left both on. After Wifi extender died without any power left, the motors stopped, And there was still 15% more in the Phantom battery. I turned them back on and after 2 seconds they stop again. Is this normal? How come you can not fly the bird without Wifi extender on? I dont remember reading about it in the manual..
 
Why are you draining your batteries ? I don't even worry about. Never had any problems with these lipos.
 
DBS said:
because it says to do so in the owners manual... and is good practice for any lipo to drain it down to 3v per cell under light load to keep the bottom end fresh and healthy... just normal stuff

Total BS, LiPo batteries do not need to be drained occasionally to stay healthy. It is actually more healthy for LiPo batteries not being drained below nominal Voltage. The DJI recommended low capacity percentage drain after 20 charge cycle is there so that the smart board in the P2 battery can relearn/calculate the available capacity since a LiPo will lose capacity with each charge cycle and with age. Same thing is done with Smartbus LiPo batteries in Laptops.
 
That is good information to know, other should test that out and confirm. When you do good to state your version of software, just start documenting. THis is my first post. Thanks!

jt_Ohio
 
Just because your statement stands ... doesn't make it accurate...

Quote from your linked website...

Charge and discharge characteristics of Li-polymer are identical to other Li-ion systems and do not require a special charger.

comments from your linked "reliable source" website...

On December 22, 2010 at 6:32pm
Lachlan wrote:
Do we have to wait until 2005 for a Li-polymer battery?
Perhaps this web page needs updating.

On January 6, 2011 at 9:44am
Ike wrote:
Lachlan, agree with you. Li-Po batteries come nowadays as standard in various products, such as new Nokia E Series phones… so it’s hardly “experimental” tech any more

I'll go ahead and get my info from THIS year thanks... :roll:
 
guess you are not used to sites where comments are listed from oldest to newest, guess what there are also comments there from 2014 ;)

And yes the charge characteristics are the same just the cell voltages differ between LiPo and LiIo
 
Panamon Creel said:
guess you are not used to sites where comments are listed from oldest to newest, guess what there are also comments there from 2014 ;)

And yes the charge characteristics are the same just the cell voltages differ between LiPo and LiIo


wow... seriously?

There are comments from 2014 because that old *** website is STILL there... I quoted some of the old comments on purpose to show that people have been disagreeing with the outdated infromation for years now...

anyway ... we know who NOT to listen to now...

And it is always good practice to follow the owners manual from the guys who make the product we are referring to... look at what they say about discharging the battery and they do mention why.
 
So tell me where does it state in the manual that "it is good practice for any lipo to drain it down to 3v per cell under light load to keep the bottom end fresh and healthy"? I looked in my P2V+ manual and even the latest and greatest PDF one and couldn't find this so please be so kind and point me to the direction of your source on that information.
 
Per the DJI wiki/ It’s recommended to charge and discharge the battery thoroughly once every 20 charge/discharge cycles.Users should discharge the battery until there is less than 8% power left or until the battery can no longer be turned on

http://wiki.dji.com/en/index.php/Phanto ... ht_Battery

Also my hitec lipo charger for RC everything is a discharger and charger and has settings to cycle lipo batteries always drops to 3.0 v/cell
 

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The lowest my RC chargers go is 3.18V per cell on LiPo for discharge and for good reason because the drop off is very steep once nominal cell voltage is reached (3.7V) and under load it can quickly drop into the cell damage above and beyond normal danger zone (below 3V). From my tests the P2 batteries seem to cut off around 9.6V which would be 3.2V/cell but I have doubts that the smart board looks at the individual cell voltages and IMO it could allow individual cells drop into cell damage Voltage if the cells are out of balance by a large amount.
 
Panamon Creel said:
Total BS,

You may disagree with a comment, but saying this is quite inflammatory. How about "I don't think this is correct"

No offence would then be taken

My 10p
 
Can someone check this and report here? Drain the WiFi extender batteries and leave the motors running to see if they'll stop.
 
chagalj said:
It happened on the kitchen table, without props on. I wanted to drain both Wifi extender and Phantom batteries, so I left both on. After Wifi extender died without any power left, the motors stopped, And there was still 15% more in the Phantom battery. I turned them back on and after 2 seconds they stop again. Is this normal? How come you can not fly the bird without Wifi extender on? I dont remember reading about it in the manual..
Back on subject after the hijack. The motors turning off and the extender charge were just a coincidence. The motors turning off is because your phantom battery was at 15%. That is a feature. You can run your motors without the extender. These are unrelated.
 
chagalj said:
Can someone check this and report here? Drain the WiFi extender batteries and leave the motors running to see if they'll stop.

I have ran out of repeater battery mid flight and it didn't shut off never sitting on the table though
 
I agree. Coincidence. It was a critical battery stage. It was not descending so it shut off. We don't know DJIs exactly logic but makes sense.
 

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