Battery Pack Series Connection Layout Help

[Eruck]

I'm building a 20s10p pack and am wondering if there would be any difference in the packs performance given the way the series connections are made (see Connection options pic.) I'd like to keep all connections on top so I could have 4 groups of 10p connected together in the grid style cell holders for pack strength. Along with having all my balance leads on one side of the battery.


My question is, Would some cells be pushed harder than others because of the flow of current through the series connections?


notes: the cells will be in 2x5 grid packs. 4 packs wide x 5 tall.

 

[amberwolf]

Depends on the resistance of your interconnects both serial and parallel. If they're able to handle more than the actual currents to be used, so there isn't a (measurable) voltage drop across them under worst-case loads, then there wont' be a voltage difference across the parallel group's cells, and the current will be flowing as needed from every cell.

Practically, having a series connection on every cell in a group to the next cell in the next group is the most ideal, as it makes a complete grid of them.

Maybe I'm just too tired or unimaginitive, but I can't picture a way you could keep all connections on one side (top) of a 20s pack, even as 4s modules. A 3s (as shown in your connection options image) can do that, but past that you end up with connections on the bottom to the next series group(s).

 

[Eruck]

Depends on the resistance of your interconnects both serial and parallel. If they're able to handle more than the actual currents to be used, so there isn't a (measurable) voltage drop across them under worst-case loads, then there wont' be a voltage difference across the parallel group's cells, and the current will be flowing as needed from every cell.

Practically, having a series connection on every cell in a group to the next cell in the next group is the most ideal, as it makes a complete grid of them.

Maybe I'm just too tired or unimaginitive, but I can't picture a way you could keep all connections on one side (top) of a 20s pack, even as 4s modules. A 3s (as shown in your connection options image) can do that, but past that you end up with connections on the bottom to the next series group(s).

Okay so as long as the connection points can handle the current the cells will share the load evenly correct?

And yes you are definitely correct on not being able to have all the connections on one side, I'm not thinking straight either. The top and bottom of layout will have contacts to the next row of cells along with the main + & -.