Copper spacer between diy battery packs

[Rasmusm88]

Hi all

I have a question regarding size of a copper spacer between the positive and negative terminals on my 14S200P battery packs.

Reason for asking is I have access to copper 15x15mm or in inches its 0.59"x0.59" in what ever length and can make it my self (cnc worker) planning to make em 2cm wide / 0.78" and a 10mm/0.39" hole through it, since my cable lugs are 50mm2 lugs with 10mm hole in it. I could probably go 8mm/0.31" center hole aswell.

But question is, is that too flimsy for 100a load from battery, will rarely see that much is my guess, but better safe than sorry?

Here is a picture of what I'm thinking -

What do you think?

 

[Rasmusm88]

So according to my own calculation, 15x15mm=225mm2 minus the center hole r2*r2 x Pi so 5x5 * 3.14 = 78.5mm2 minus 225mm2 = 146.5mm2 copper from that block is this wrong ? And I guess 50mm2 is enough to carry 100a @ 48v. So my copper spacer is a succes hehe

 

[OffGridInTheCity]

Not picturing what you're doing... but if it helps, I use these lugs (dimensions below) bolted to my 14s100p batteries to carry up to 400a thru 4/0 wire. I routinely run 200a with 300a peaks for a few hours a day in summer - with no heat.

https://www.amazon.com/gp/product/B073CLMLHZ/ref=ppx_yo_dt_b_search_asin_title

 

[Rasmusm88]

They go inbetween these, just to make some space between the packs

Oh and I see the picture is gone will edit it

 

[OffGridInTheCity]

They go inbetween these, just to make some space between the packs

Oh and I see the picture is gone will edit it

Thanks for the clarification/pic. How many amps do you expect?
Perhaps saw off 1/4" copper pipe sections as 'spacers' (or use a stack of washers) and fasten inbetween with bolt/nut - the bolt will carry current as well.

 

[floydR]

On a separate Note is the bar the battery pack is on metal? Perhaps add some insulation at the bottom of the connections. Looks like a short could happen quite easily.
Later floyd

 

[Rasmusm88]

True about the bolt will carry current aswell, didn't think about that hehe ..... do you think my calculations are correct for that copper spacer? My multiplus II 48/5000 will do 4000w continuous, so at nominel 51.8v it's 77Amps. But can peak at 9kw for seconds

Hi Floyd, great point but picture is temporary location for storing it still in progress of finishing up my shed. And permissions for the installation.