Gens Ace 3s w/ a single higher Vdc cell

[druz]

I got a Gens Ace 3s LiPo when I got my Yeti.

All was (is) well, however I noticed that when charging it, the charger (Onyx 245) eventually times out. Didn't think much of it at first, but then it started to set off a tiny red light in my mind. After RTFM, I cycled through the Data options and noticed cell #2 is running 4+ Vdc while the others are clocking in around 3.6 - 3.8Vdc.

Taking a SWAG at this, I assume that the charger is trying to balance out all the cells, but with one running "hot", that is causing the charger to not give me a proper "Complete" cycle?

I do not have the same issue with the Venom 3s I have.

Doesn't seem to be an issue, as the battery has performed well every time I use it.

Any thoughts?

TIA "thumbsup"

 

[Ninomaniac]

That is very strange. Not that the cells are off but that it performs well as you say, and that the charger can't balance it (balancing is exactly the process of getting rid of voltage differences). I'd be wary of using that charger and/or battery. How does it do with other lipo packs?
Going by the voltages, only one cell is full while the other 2 are below storage voltage. You would NOT get a lot of runtime this way.

 

[druz]

All other Lipos are fine (venom 3s, dynamite 2s, bunch of small 1 and 2s for drones / plabe).

This is what is making me thinking is just the battery. I will slap it back on the charger when I get home and check the cell Vdc readings.

 

[druz]

Just put it back on the charger. Readings as follows:

cell #1 : 3.8vDC
cell #2 : 4.1vDC
cell #3 : 3.9vDC

reading a steady 12vDC when cycling through the Data button readings.

Like I said before, seems to work just fine. Guess I will just keep an eye out on it and go from there.

 

[Jboucher]

I always been told that once the cells are uneven, it's bad battery and it can be dangerous.

Sent from my Nexus 6 using Tapatalk

 

[Ninomaniac]

Won't last long, looks like 2 of the cells are in really bad shape

 

[Hydrocarbon92]

Just put it back on the charger. Readings as follows:

cell #1 : 3.8vDC
cell #2 : 4.1vDC
cell #3 : 3.9vDC

reading a steady 12vDC when cycling through the Data button readings.

I have a feeling something is wrong with the charger. They use different chips for reading overall voltage & individual cell voltage, and 3.8+4.1+3.9 does NOT equal a steady 12v.

If those are the correct readings, something really went nuclear in that battery for 2 cells to die. Usually a puffy cell will be 0.1v or maybe 0.2v off, but the chances two to be 0.2-0.3v low is like having a grand piano dropping on your crawler.

I am curious what voltage you normally see on your fully discharged batteries. Anything below 3.5v will damage cells over time.

 

[HumboldtEF]

I've noticed that my low voltage meter seems to have totally different reading than my charger which has always bugged me. I just put a 3S lipo through a storage charge and my charger shows 3.90, 3.90, 3.90, but my voltage meter reads 3.86, 3.90, 3.80 right afterwards.

I'm not sure which readout to trust, I hope its the charger as its dead on. maybe I should hook up a mutlimeter to see what it shows.

Any thoughts?

EDIT: I hooked up a multimeter and I guess I need to do a bit of math as only the black and yellow wires show a single cell, black and blue shows 2 cells together and black and red all 3, so in the same order I got 3.87, 7.76, 11.63 which if my math is right looks to be 3.87, 3.89, 3.87 (storage charge LIHV), this battery has only been used once BTW

 

[druz]

I've noticed that my low voltage meter seems to have totally different reading than my charger which has always bugged me. I just put a 3S lipo through a storage charge and my charger shows 3.90, 3.90, 3.90, but my voltage meter reads 3.86, 3.90, 3.80 right afterwards.

I'm not sure which readout to trust, I hope its the charger as its dead on. maybe I should hook up a mutlimeter to see what it shows.

Any thoughts?

EDIT: I hooked up a multimeter and I guess I need to do a bit of math as only the black and yellow wires show a single cell, black and blue shows 2 cells together and black and red all 3, so in the same order I got 3.87, 7.76, 11.63 which if my math is right looks to be 3.87, 3.89, 3.87, this battery has only been used once BTW

I did the same thing last night and it almost matched my charger perfectly. I tried to charge at a lower amperage per Gens Ace tech support and got the two "low" cells to come up. I will keep an eye on things and report back...

 

[HumboldtEF]

so your charger reading matched your low voltage meter? maybe I need to get a different one or just ignore the cell readings

 

[Ninomaniac]

Those little beepy low voltage alarms are crap for measuring voltage. Good only for ESCs without cutoff so you don't ruin your battery, but for any serious measurement you need a voltmeter or a good charger.

You can measure individual cells directly between two adjacent wires (yellow-blue, blue-red).

 

[HumboldtEF]

Thanks Ninomaniac, very good to know.

EDIT: I just checked the cells again with my multimeter after a charge and its perfectly balanced and my charger is accurate which is great to know.