Charging LiIon Cells - What's Up?

[aLyr]

Hello all,
yesterday I had an unusual experience.

I own 2 mods which take 2 16350 cells each.
Those are a vaporesso Tarot Pro and a vaporesso Revenger.

Of course, I use them with matched pairs of LiIon cells.
I have three of those pairs for two mods, namely
2x Samsung 35E
2x Samsung 30Q
2x Sony VTC6
Please do not complain, as all of these cells are perfect for my style of vaping!

But back to yesterday.

First, my Vaporesso Revenger showed a "low battery" message.
It had 2 Samsung 30Qs installed at that time.

Thus, I had to replace those cells with a pair of Samsung 35Es I had.
So far, so good.

Now it came to charging the depleted 30Qs.
This has been quite amazing. Before charging, the cells had resting voltages of about 20 mV apart.
My Nitecore SC4 charger, however, stopped charging at the same point in time for both cells!

Shortly thereafter, the Tarot Pro also complained about a low battery status.
Thus, that cell pair had to be replaced also.
The mod got the freshly charged 30Qs.
But it had a depleted pair of Sony VTC6s inside, which I recharged, of course.

Clearly, these VTC6 cells had to be newly charged.
But anyway, while charging, these cells showed the same behaviour as the 30Qs.

Again, for both of the VTC6s the Nitecore SC4 charger stopped at the same moment for both cells.


Regards,
aLyr

 

[Mr. Relentless]

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[mimöschen]

Not necessarily. If both cells show 4.2V after charging, there shouldn't be a problem, and a difference of 20mV at the start of the charging cycle isn't that much of a deal anyway. Up to a certain voltage, the charger charges with the max selected amp, then cuts down drastically and brings the battery very slowly up to the full 4.2V. The lower battery will still be charged a bit slower, but not noticeably so.

 

[sonicbomb]

I own 2 mods which take 2 16350 cells each.

Did you mean 18650?
I don't understand what the problem is you are trying to describe.

 

[DaveP]

20mv is a .02v difference. One volt is 1000mv. That's normal operation. All cells aren't created equal and your mod may draw minutely different current loads from each cell during operation due to contact resistance during discharge and cell manufacturing variances. What you are seeing is within the design parameters of the cell.

Contact resistance also plays into the issue. Sometimes, I see slight voltage variations on my charger display while it's charging. When I use my thumb to rotate the cell, the voltage reading jumps and matches the other cell(s).

 

[stols001]

Some mods will stop use if the difference in batteries becomes more than a certain percent (at whatever voltage is left). IDK though, that appears to be a much less difference than most mods would register so IDK. Could there be something faulty going on with your mods electronics? It's possible it's the charger, but I don't think it's likely.

I have a few mods that get unhappy if the batteries aren't discharging evenly, but really, it hasn't h happened to me much.

You could get a different charger and see if it "solves" the issue, although I'm not convinced it is a HUGE issue to begin with, and it's a bit hard to understand what is going on with the information you are giving. Etc.

Best of luck ,but if you can offer up further info as it were, I think your answers may be a bit less speculative. Etc.

Anna

 

[Mr. Relentless]

My bad I read it wrong.