asking for advice

Hi everyone,

I bought some 16s packs from an BEV and have them connected in parallel to an inverter.

I was wondering how others would have done this...

Specifically,if you have 2x 16s1p assembled packs would you:

1 -connect them both to a busbar (via fuse)and then busbar to your inverter? (this is what I currently have)
2 - connect each pack together at the balance leads with fuses? i.e. make it 16s2p
3 - some other way?

I ask this question mainly because now that I am thinking of adding a BMS, it's not really economical to put a batrium longmon on each individual cell.

So any advice?

Thanks!

Options 1 and 2 are fine. Option 2 is a bit better as it helps keep 2 cells in balance with each other. So, you could do a combination of 1 and 2. Connect the main power leads to a busbar (or heavier gauge wire) and connect all the balance leads together.
Then you can connect 1 bms to both packs. You could do this for a large number of packs, 80 or more in parallel, and not have any issues.
To help with the balancing portion, you could connect all balance leads to a strip of 12swg wire that runs along the packs connecting all the balance leads. Ohh, and yeah, I'd use a fuse at that point for each balance lead as now current can pass from one pack to the other.

Battery pack -> Fuse -> Busbar -> Fuse -> Inverter

Fuse everything.... less damage when thigns go wrong..

Depends on the cells and accesibility to the cell contacts for a BMS.

One approach I am looking at is to connect packs together for balancing via 1A to 3A glass fuses via a 0.27 Ohm 3W resistor (my ceell voltage is a little different) .
Each cell(s) would then be : Cell(s) connection -> Glass fuse -> 0R27 Resistor -> Common BMS bus

For your setup you could probably just wire all the cells together into a single larger pack or a larger pack size without the fuse and resistors...

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The cell to cell imbalance flow will depend on your overall power draw and the series cell imbalance. Typically if you have 3A flow through each pack the flow between interconnected packs would be small <500mA unless you then have a cell failure within one of the series packs and then you could end up with around 2A flowing. Scale this up and your wires have to get bigger or just add fuses as Korishan noted.