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Bending Copper Bus Bars

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guidecca

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What is the best way to connect the battery positive and battery negative terminals (BC0 and BC8) on the cells to the BMS and the + bus bar? I want to bend the copper bus bars to 90 degrees, run a 3/8" stainless bolt through the wooden compression wall for the bus bars for battery positive and battery negative, connect 1/0 awg wire to each and run both wires out a hole in the battery box. From there to the fuse, bus bar, or fuse and BMS. Is there a good way to bend the copper? Can it be heated and bent?
 
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guidecca said:
What is the best way to connect the + and - terminals (BC0 and BC8) on the cells to the BMS and the + bus bar? I want to bend the copper bus bars to 90 degrees, run a 3/8" stainless steel bolt through the wooden compression wall & through the + and - 90 degree bus bar, and connect my 1/0 awg or 3/0 awg wire there and run it out a hole in the battery box. Is there a good way to bend the copper? Can it be heated and bent?
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comment deleted…J.
 
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Worked with copper in my blacksmith shop to make ornamental items and even after a short period of hammering on copper would go back to the fire and heat it and then cool in water to soften it so as not to have it crack or split when shaping it.
 
Opposite. Copper goes soft with quenching and you slow cool or work it to harden.
 
What are the LiFePO4 battery terminals made of? The 3/8" stainless steel bolts hold the 1/0 awg lug down onto a copper bus bar. How much resistance is present? The only equivalent copper bolts were for sale on E-Bay. The big box stores have copper split bolts.
 
guidecca said:
What are the LiFePO4 battery terminals made of? The 3/8" stainless steel bolts hold the 1/0 awg lug down onto a copper bus bar. How much resistance is present? The only equivalent copper bolts were for sale on E-Bay. The big box stores have copper split bolts.
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I was thinking the bent bus was on the inside and the wire lug was on the outside. You don't want a copper bolt, it will stretch. Holding a lug to a bar doesn't need any conductivity (it's all about surface area/tension).
 
I heat copper pipes in the woodstove, flatten/shape them with a hammer and then drill. They soften/anneal quite a bit even before glowing hot, but glowing is ok too. Quench or slow cool is OK.

They will work harden as you hammer and bend them and you can reheat if further work is needed. The copper surfaces will mate better after annealing also. It's a great way to make beefy buss bars. I made 1000 Amp bus bars from 1 1/4" pipe to connect a bunch of MPPTs, inverters and batteries together with little or no voltage drop.
 
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The bolt conductivity is negligible. The contact between the lug and the bus bar is what carries current. If you need to pass it through a bulkhead they make a fitting for that. Something like this, they make many types and sizes. Nickle plated copper

www.westmarine.com

5/16

Check out our 5/16
www.westmarine.com www.westmarine.com
 
I bought some 1/8" x 1" copper bar stock, held it in a vise, and bent to 90° with a hammer. Not sure of the alloy but it was made to be used as a buss bar. It bent easily cold with no cracking. I use stainless steel bolts to attach it to the battery terminals and to attach cables. Stays cool at max load.

Edit: 110 Copper is 99.9% pure copper with an electrical conductivity rating of 100+ % IACS.
 
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Others can answer but I am pretty sure you want smooth curves rather than sharp corners....

This is from lots of reading and memory so look it up.

I think there is a spec for minimum turn radius. A sharp hammered corner can/will result in a hot spot due to fractures in the structure of the metal.

You might get away with it by redoing the annealing but heating red hot and slow cooling it.
 
Found a few references for it, thay say minimum radius is equal to the thickness of the bar so 1/8 for you and all is right and happy in the world and dogs and cats can sleep together
 
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