[kennybobby]

i hope those are real cells and not fakes, that added label is kinda flaky and there appears to be no marking as "Panasonic". It is hard to find info on whether or not these cells are internally protected or not--there are numerous websites advertising them, some say yes others say no...

Panasonic datasheet indicates rated capacity at 3200 mAh, but it varies so much with both temperature and discharge rate that almost any value could be quoted.

i wonder if the datasheet has transposed the digits of the weight, then your measurement matches exactly.

 

[kennybobby]

Can you carefully measure the overall length (without shorting the ends)?

 

[kennybobby]

...

Being in parallel, the stronger cells will supply more current proportionally while the weaker supplies less, and thus the weaker cell cannot get over-discharged. Their voltage will always remain equal. If the current is cut, and the five cells separated, the five in parallel will have same voltage. One weak cell cannot disproportionally reduce the voltage when in parallel.

But your BMS is not monitoring current, so how will you know when the weak cell has been depleted? How will you not over-charge the weak cell? Do you have test data or experience that indicates your statements hold true?

"Cells in a parallel group cannot be individually monitored for voltage or SOC, or protected against over discharge, so need to be well matched."