TB47 Batteries

[DigitalDrone]

Hi Everyone,

I have two batteries that are acting strange and hopefully someone here can answer what the problem is.

I don't have much knowledge on how these batteries work.


All these batteries were fully charged at 100%

1st battery: As I lifted off I noticed the voltage went from 4.2v to 3.6v almost instantly and on the menu 1 cell (the first one) went to Yellow while the others stayed green. The battery was at around 80% ish. I recently deep cycled this battery as it has around 20 cycles on it.

2nd battery: As I lifted off it went from 4.2v to 3.6v instantly and then down to 3.5 shortly after when at 77%. When at 3.5v all battery cells went yellow. This battery has 18 cycles on it.

I heard that if the voltage goes down to 3.6 the drone should be landed asap.

FYI, these batteries were stored at 50% for a couple of weeks and then topped off before flying.

What is going on and what should I do? Are these batteries finished??

 

[fofun]

I've noticed something like this before with my phantom batteries in the past. I learned years ago that lipo batteries like to be slow charged as opposed to quick charge. I charge all my batteries at about 1.5 to 2 amps. It takes a while to charge them but it's worth it to me.
The chargers today charge at a higher amperage and the batteries don't last as long as they should. I have 3 old phantom 2 batteries that are still in great shape and hold a charge very well.

I would try to discharge one of your batteries all the way down, then slow charge it, and see what happens. You won't be out anything by trying it. It might revive your battery.

 

[giumick]

I learned years ago that lipo batteries like to be slow charged as opposed to quick charge.

Cheap batteries that is. I have always charged double capacity on my hobby lipos (overlander etc) and nailed them with 3d aerobatics. Years later only one has started to loose its punch but my inspire batteries less than a year old are asking for a deep cycle already....not good. Alot of lipos take 4-5 times capacity these days but you are pushing them then and will experience a noticeable loss of life.

They should take heavy charge cycles in the field and recover with a nice slow balance charge at home to settle them down.

They sound like they need a discharge though a fofun said

 

[DigitalDrone]

I've noticed something like this before with my phantom batteries in the past. I learned years ago that lipo batteries like to be slow charged as opposed to quick charge. I charge all my batteries at about 1.5 to 2 amps. It takes a while to charge them but it's worth it to me.
The chargers today charge at a higher amperage and the batteries don't last as long as they should. I have 3 old phantom 2 batteries that are still in great shape and hold a charge very well.

I would try to discharge one of your batteries all the way down, then slow charge it, and see what happens. You won't be out anything by trying it. It might revive your battery.

To what percentage would you discharge?

How often should I deep cycle the batteries?

I had these batteries sitting at 50% for a couple of weeks while waiting for a repair and then just topped them off yesterday before flying. Do you think this played a part in the problem?

 

[fofun]

To what percentage would you discharge?

How often should I deep cycle the batteries?

I had these batteries sitting at 50% for a couple of weeks while waiting for a repair and then just topped them off yesterday before flying. Do you think this played a part in the problem?

 

[fofun]

I would run the inspire off the ground about 3 feet and run the battery until it lands itself. Let the battery cool down completely before fully recharging it.

DJI recommended every 20 charges to cycle the batteries.

I think it is just a coincidental thing as to how it happened. A lot of times if the battery isn't charged completely or often, it messes with the circuitry some what.

As I have said it happened to me in the past and I have done these steps, and my batteries are fine. That are also 3 years old and have many flights on them. Hope this helps.

 

[CCDD]

I deep cycle after every 15-20 uses. I still only see 11-12 minutes of flight time on TB47 and perhaps 14 min on TB48 with X3 camera and very conservative flying

 

[Bob Stekeur]

sounds like a bad cell