Disassembling a Prismatic Pack

[1ufvlsi6x]

What I want to know is how to remove welded bars and put new ones properly. Theoretically there could be a new series using the old bars and saving the hassle, but maybe we want to make pairs of them first for a 2p16s.

 

[bushytails]

Use an annular cutter to remove the old busbars, drill your new busbars to the ID of the cutter, then laser or TIG weld them to the cells. Or some other procedure that's probably more work than it's worth unless doing large quantities with jigs...

 

[1ufvlsi6x]

Drilling sounds dangerous unless it's precision equipment and on perfect cell spec which is unclear.
It seems smarter to unweld nothing and keep the series as-is and put a new BMS only.
But it's lame because I wanted to make 2ps first before the 16s (32 small 100Ah cells).

 

[bushytails]

Bolt wires to the busbars to parallel the cells. That's what I plan on doing, at least.

 

[1ufvlsi6x]

Bolt wires to the busbars to parallel the cells. That's what I plan on doing, at least.

Yeah I got that's you meant, first cut the bars in half and then drill in them instead of endangering the cells themselves.

But that's not perfectly clean so if I'm going to waste the equalizers and buy a BMS I want it to be well done at least.

 

[davros]

is there enough meat let on the tabs when halved to bend “ears” upward, easier bolting
If the tabs are welded OK I would not mistrust them inuse

 

[bushytails]

For paralleling cells between two modules, these modules already have threaded (brass insert) holes on every busbar, which I plan to use. For making a pack out of the two cells off the back of each one, there's enough length you can bend them upwards and bolt, or I might try TIG. If I bend them, my plan is to clamp a piece of metal on top of the busbar, so I can bend upwards without bending up on the cell connection.