looking for recommendations for BMS upgrade

A follow up question, if I may :?

I'm looking at the design of my build and it would work better if I stacked the battery cells like this:



I realize/understand that the board on the top:



is there to facilitate the connections of the battery leads. I'm sure that I could fabricate a new mount board out of prototyping board or fiberglass sheet and a box so that the cells are properly supported.

Is this possible and what problems should I look out for?

Thanks!

Unless you pack the cells like they already are, as a "brick", you can't apply even compression across their faces (without building something with individual cell compression plates and edge-mounting hardware).

Without even compression, they're going to swell/unswell, even if it's just minutely (and possibly up to what's often called "puffing", which means gas between the layers, which means those areas of the cell are effectively "dead"--can't conduct thru them anymore. Increases the resistance of the cell, and the load on the still-flat areas, which can cause more gassing, which kills larger areas, etc. Once this happens even a little bit to a cell, it's never going to be like it was. (even if you can somehow get the gas out)

That's the one big problem with any kind of pouch cell, is that they require even compression across their faces. Some, like the EIG cells I have, are less susceptible to the problem, but it still happens under higher charge or discharge rates even with those, especially as it gets closer to the empty or full end of charge.

So in short, no. OK, so I'll rework my design.

Thanks amberwolf!