lipo question

[kloner]

Andy, i have a 4s i got from HP and ever since i've had it, the individual cell readings have been strange. cell 1 will go from 4.2 to zero, and cell 2 goes from 4.2 to 8.4, they just go up and down, up then down, but at the end of the charge, the voltage is 16.8. If i didn't plug in the ballance cord, you'd never know it was happening. runs and charges normal.

Am i begging for a fire or do you think the ballance lead is just malfunctioning? It's not swelled what so ever, never been hot, ideas?

[yadac123]

well it's normal for the voltage to jump up and down be during balance charging the charger will try to do this. It's like filling the container to 100% full. When the container is 95% full you have to slow down the water flow and slowly fill it up. which charger are you using?

Andy

[kloner]

Thunder t6 from you

I'll take a video and see what you think. It seems like something is malfunctioning. I can not believe that one of those cells is at 8.4 volts to make up the 4s pack, but thats what the charger says. I only have one charger and one 4s battery so i have nothing to compare it to. The 3s does not do this.

[yadac123]

ok show me a video or a picture and I'll take a look at it.

Andy

[kloner]

I tried the video but it's really hard to see. This is a photo of what it looks like at it's worse, then cell 1 will go up to 3.76 and so will cell 2 that you see pictured at 7.52, exactly double.

I've used the battery a few times, never got it hot, never over discharged. Battery has acted like that since it got here. I Fly it on a mustang foamie that is too fast for my house to land so it doesn't go up much.

I've got 14 3s batteries from you that all run at least once daily and none of them do this

[yadac123]

ok try this for me. I want you to use the discharge function to discharge the battery to 12.0V then use the balance function and bring the battery to full. Let me know. It could be the battery that's having issue or charger.

Andy

[kloner]

OK, i got it discharged, it did the same thing all the way down to 12.6  with the voltage going to 0 then back up to match then the charger crashed and said incorrect volume cell count, so i reset it without the balance leads and hit discharge again, it went to 12 volts in about 20 seconds and finished. Hooked the balance lead back up hit balance charge, no go. Incorrect volume error. Unplugged the balance lead and charged at 1 amp for 2 hours, and the charger timed out. I then plugged the balance lead up to the charger, hit .2 amp balance and the voltage is still going back and forth, but not as low. Lowest i could get on the camera was 2.16 on cell one with the remaining voltage showing in cell2. The battery is not hot, no puffing, no shorting. Weird

I plan getting some 4s batteries from you in the near future and i need to get this ironed out before this happens to em all.

Is there anything i can diagnose on the balance plug adapter that the battery plugs to? It seems like an electronic switch malfunctioning.

The battery now sits at 16.5 volts and i just put 1999 mah in it, after all that work. It is a 2200 25c4s green lipo

When you gonna get me some bigger gear? I need some 6s battery, would love to see some higher end full size heli grade servos , gyros and motors too. Nitro type gear

[yadac123]

ok then I think your battery has problem because once you discharged completely, the charge should not read error when you are trying to recharge it again.

Look at the battery you have, do you see any cell puffing up?

Andy

[kloner]

here are some pictures

[kloner]

more

I don't see anything standing out that says hey, that one looks different than anything else i have. Got it from you a month or so ago

[yadac123]

ok I'll have you send the battery back and I'll take a look at it. what's your order number?

Andy

[kloner]

Thanks

order yhst-62196343123315-8184

[yadac123]

ok rma issued.

Andy

[yadac123]

ok buddy,

I got your battery back and it has no problem. This is what I did. I completely discharge the battery down to 12V and then recharge it back to FULL and all 4 cells are functional and no problem at all.

What type of charger do you have? most charger's balance function, at the end, flucturate the current to slowly balance the battery.

I'll send the battery back to you.

Andy

[kloner]

That is the same thing i did and i sent you what it really did. The charger is also from you. It is a thunder t6, a couple weeks older than the battery. This week i had a balance wire break off a 3s i crashed. When i put it on the charger, cell #1 & #2 did the same thing that one did to me. So i'm guessing it has a broken balance lead.

Go ahead and send it back, i'll just throw it out with this 3s i've got broken, i run these too hard for them to not be getting balanced right and to risk killing any more models