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How does one prep Copper Bus bars?

3064 Views 5 Replies 4 Participants Last post by  madderscience
I am not the best a chemistry,

but I've been read that with copper bus bars for batteries, that you need to prep them to avoided Copper Oxide from forming and increasing ohmic resistance and causing heat to build up leading to cell failure. and also to prevent galvanic corrosion of contacts terminals. ( I am using 82 Ah Nissan leaf batteries)

I've heard of nickle plating the bus bars and a few other ways. but just want a more technical explanation of how to go about connecting up the cells without damaging the batteries or causing any galvanic corrosion
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I've got some bare copper bus bars I made when the cells I have didn't come with enough factory ones.

My prep method is to sand the contact surfaces with a fine grit sandpaper enough to get a bright shine. then, rub a VERY THIN layer of a conductive antioxidant compound like noalox onto the contact surfaces and assemble. So far, no issues. (36000 ev miles and 4 years)

Assuming your cell modules are reasonably protected from weather you should not have too much trouble with oxidization or galvanic corrosion. Oxidized gunky bus bars were much more trouble with old liquid electrolyte batteries like flooded lead and flooded nicads.
Been in Telecom for 40 plus years and have had so many copper buses I cannot count. You are on the right track, just need some tweaking. Really pretty easy.

1. Get some Green 3M Scotch Brite. buff mating surfaces off. No need to do the whole bar, just where terminals will terminate. Buff just enough to get a bright shinny surface.

2. The absolute best antioxidant hands down is San Chem No-Ox-Id A Special. It is the only thing electric utilities, telephone, Cellular, Water Departments will allow to be used. There are battery plants on the coast with salt air in service for 40 years using this stuff. The only trick is to use a very light coating.

3. So prep the bar, be sure to buff the connector lightly, and apply a light coat of No-Ox-Id.

4. When you stip the wires for the compression terminals apply a light coat of No-Ix-Id on the wire skinner, and the inside of the compression barrel. A trick I learned a long time ago by Installer is they use a hot plate with a tin cup full of No-Ox-Id, and heat it up. They dip their wire skinners , and shake excess off. They also use a small paint brush to paint surfaces with a light coat and then wipe off excess with a clean rad.

Here are some places you can buy N0-Ox-Id in small quantities. Even a 1-ox paper cup will last you a lifetime. All you need is about $5 worth in the little paper cup you see in the link.
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Thanks guys, what about Nickle plating the copper busbars? is that worth looking in to also? of is the Noalox and NO-OX-ID better options? which is best? No-Ox-ID or Nickle plating? are there pros and cons?
I'm sure you can buy nickel plated bus bar if you really want to, but as long as your battery connections are reasonably well prepped and protected from the elements it isn't likely necessary. Obviously different people have different opinions on the best antioxidant compound, but again unless you are doing an extreme build intended to run in extreme environments it probably won't make much difference. The prep and proper application thereof is going to be more important than the brand.
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