It’s been a while since I’ve made a post, so I’ll try to do my best .
This is a brief walkthrough on assembling the custom 12S-3P pack module, this system is use in parallel on a 9P or 12P configuration.
PCB
I’ve made this in order to save time wiring, low profile, proper separation of cells and a few more reasons…
Cell configuration
The cells are configure into 2 identical 6S-3P stacks as in this picture
The series connectors plates help with alignment and the balance tabs connect to the pcb, also the balance tabs are oriented to match the solder pads on the pcb.
Pack A, negative side.
Pack A, oposite side.
Pack B, positive side
Pack B opposite side.
Packs positioning side by side, Pack A in front.
Attaching packs to PCB
For this the balance tabs are aligned with the corresponding solder pad and spot welded into place.
Then a separator goes in between the packs with the help of 300LSE tape.
Next is pack B
The series connection from pack A to B is made by using a 3 layer nickel strip.
Now add isolators side pads
BMS 30A and balance connector.
Next shrink wrapping.
The individual enclosure for this packs are made from aluminum and powder coated with a notch for the discharge wires.
The trays can be aligned side by side.
I use fiberglass tape for rigidity and cover with flashing tape to seal it, this configuration provides the best flexibility and proper water resistance.
The packs fit tight into the tray and we use silicone to glue the packs to the tray.
Now you can assemble this into a 12S-12P, or 12S-9P.
Next is the parallel connection.
Since each pack can discharge up to 30A the total output will be from 90A to 120A, but in real world situation I’ve never pulled more than 60A from a battery pack.
This are the main discharge tabs.
A 12AWG wire is solder directly to the tabs and to the output and charge port.
For the 12P
For a 4x4 set up the discharge wire con be extended to both ends.
To seal all up a double layer of 300LSE tape and a plastic cover.
That is all for now