Lets agree to disagree.
As the Scotch tape is elastic, the movement will take place there where there is the least resistance.
In this situation, not the top where the terminals are located, but at the bottom.
The 3 parallel cells will expand a little to the side, but have space to do so.
The 4 strings on the long edge.... 0 to almost 0 expand/contract movement, = no stress.
My cells are build-up at +/- 85% full charge stage (3.30625v) and will not be charged over 3.4v
3.65 is dangerous maximal voltage that is better not to reach.
It's a known fact that lithium cells live longer when they are not top charged.
Charge difference is about 2% from 3.4v to 3.65v. Only 2%... unless you really, really need it... better stay in the lower range.
My cells are already at high capacity and will be little more to 3.4 when my BMS arrives.
As I made them during the "full charge" they will almost nothing more expand.
During discharge they might contract, there is room for movement.
now on the concrete floor, later on wooden plank.
unless there is a earthquake, I don't have to be afraid for any vibrations in my home / installation.
Yes, Scotch tape is not always the best solution in all installations.
Installations with much vibrations like RV or electric scooter Duct-tape can be better, or metal clamping strips, or....
there are many different options all with their own good use in their own environment.
For me, not moving home, one time placement location.
Packing the cells for parallel as set of 3 with Scotch tape is the most convenient solution for placing.
They don't need any tape or any additional support as there is no movement.
For the individual cells expand/contract... if you place them in expanded stage (full charged), there is no expand force!
Contract movement is not a problem, having a few tenth of a millimeter, or maybe a millimeter space gap between the cells is good air ventilation
better cooling during charging
I might change the S for the 2 x 3 cells to connect.
I'm aware that it is better to make 8 shape but i don't have enough bus-bars to do so
With E shape, there are 3 bus-bars stacked, with one that need washers to stay flat.
This S shape reduces this.
I measured the voltages all ways, any direction and I could not measure difference.
I can understand that with the S shape resistance is not totally equal for each individual cell.
I could not measure the difference, my multimeter is not sensitive enough.
At 200 ohm it gives 00.1 resistance when I connect the measurement probes to each other, and it stays like this on every location between terminals.
That is start and end of the S, or any place in between, or the long line of 6 cells begin and end.
all 00.1 ohm.
I'll probably make bus-bar with 3 holes to make a nice 8 shape from some flatten copper pipe in the near future.
At the moment still waiting for the BMS to arrive...
in between time...
is there a real reason not to use S shape but change to E shape??