Typhoon H - Strange Battery Behaviour

[kayakmtb]

I thought I had a dead battery yesterday. It was the original that came with the H and every time I plugged it into the A10 charger it showed a cell error. The cell voltages looked like this:


Note: on the basic charger it just cycled between green and blue. Using a multimeter on the contacts the voltages were similarly unbalanced.

However, today, after leaving it a day I plugged it in for 1 last go, and it appears to be charging fine!

Anyone else had anything like this and knows why?
Or is it just these temperamental LiPo's?
Or is the A10 charger playing up?

Thoughts anyone?

 

[gwhuntoon]

Sometimes a single cell in a pack can have it's voltage drop below or vary enough from the other cells to a point where a charger can't deal with it. Occasionally letting the battery sit on a balancer can actually bring the cells low voltage up to the point where it can either be recharged or is more in line with the other cells so the charger can deal with it. Sometimes this works, some time it doesn't.

 

[CraigCam]

I thought I had a dead battery yesterday. It was the original that came with the H and every time I plugged it into the A10 charger it showed a cell error. The cell voltages looked like this:


Note: on the basic charger it just cycled between green and blue. Using a multimeter on the contacts the voltages were similarly unbalanced.

However, today, after leaving it a day I plugged it in for 1 last go, and it appears to be charging fine!

Anyone else had anything like this and knows why?
Or is it just these temperamental LiPo's?
Or is the A10 charger playing up?

Thoughts anyone?

Did the voltmeter back up the rebalance? I have had similar readings but they are from the balancing pins not making proper contact on the charging cable. Try connecting to the charger and wiggle the connection. See if that makes those reading happen again.
Also, did you check resistance with your charger? If there is a suspect cell, it will be way off the others. It’s weird cause it’s usually an inner cell that gets funky first. The OEM batteries after awhile show readings in the teens typically and a bad cell will read 3x over the average of the ohms of those good cells. The cell with the high number can charge normally but discharge rapidly and it really needs to be under load of the motor amp draw to show it’s true behavior. For this reason, once I loose faith in a battery like that, it becomes set up only. I put bright paint on it and use it for calibrations and satellite collecting.

I’ve bought Yuneec batteries that came out of the box out of balance and out of line in resistance values. The usual cause is heating up during shipping unfortunately and there is some old never used batteries still out there. You can bring them into better values with some flying and balance charge cycles. The key is to never fly into any voltage warning level and your batteries last a long time. That’s of course impossible sometimes so all your batteries take those hits and they die a little. Never leaving them in your hot car is a must also. I recently puffed up two that way.

 

[rdonson]

As @CraigCam says, I've experienced this several times and its been dirty contacts. A shot from this on the battery and on the charger has always cleared things up for me.

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[kayakmtb]

@CraigCam @rdonson. Thanks guys. I have found that if a battery hasn’t quite reached ambient temperature (nothing scientific , just by feel) I am more likely to have a problem. Also sometimes a voltmeter check is normal. I suspect as you say some of this is dirty contacts. As for battery voltages in flight the lowest I land with is 14.7.

Thanks for the advice guys!