ideas on setting up 4s20p pouch cell battery bank

Hi All, i have around 80 lipo pouch cells.actually 80x2 as while harvesting them from old laptops they were already 2xparellel and i found it easier to take them out in pairs. however for simplicity lets refer to them as 1 cell.

They have been sitting with we for a while as i didn't know how to handle them. there is lot of info on this forum and other places on using the 18650 form factor, there is hardly any on pouch cells. However recently due to the covid situation i have some spare time and i decide to work on them. I have started soldering wires on the positive and negative terminals as you can see in the second pic.

my plan is to have 4s20p. i am struggling on how to do the wiring, should i use nickel or a bare copper cable and solder the other end of wire from the battery? if so how do i insulate it. or should i use a terminal connector strip and screw the wires each. also any ideas around what kind of case i can use or create.

i want to have a 12v 80ah battery pack with some 4s bms that i have not researched on yet. Also i am not sure how i will be using this battery. most likely i will pair it with an inverter an use as a backup power.I am taking it step by step and the first thing i am trying to figure out is how to create this 4s20p battery.

Thanks for your help in advance,
Mike

Moved to Battery Pack Design, Planning, and Building

Hi Korishan, apologies, thanks for moving it to the correct group.

I know what you mean about 'not as much info' - I'm 18650 myself.

One key thing about pouch is they need to be 'contained' (flattened) in a firm container or between firm plates holding them flat.
You don't have to 'squeeze them' - just some kind of physical way to not let them expand. Typically you can lay them against each other - like a stack of pancakes - with a firming plate on each end, perhaps held with threaded rod or stuff them into some kind of rigid container. This is because even under 'regular use' they can start poofing/bulging up and this will start causing early battery failure (loss of power etc) as the internal medium separates.

As far as connecting them, I've noted that people do eyelets/drill (for bolts) or solder or any way that's good for you to connect to the tabs. I wouldn't worry about how you do it so much as basic battery issues - e.g. make sure the wire/connection (bus) is adequate for the current you plan to run. Maybe create a 'base battery' with a specific number of pouches in a physical constraint design with a circuit breaker and then hook them in parallel.

A couple of youtubes I've seen on connecting tabs:
@jehugarcia (lighter approach) - at 5:29 you can see his approach - Build SPIM08hp LiPo into 7s 24v packs with BMS @DavidPoz (heavy duty approach) - LG 6kwh Powerwall, Part 1, Joining Cell Tabs Together -