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darryl
03-22-2011, 03:04 AM
I need to build a battery box to hold 8 c cells. I'm thinking to possibly break from tradition and try using stainless steel sheet material to make the contacts from. I know it's not the easiest to make a soldered connection to, but I could always lay out a dozen or so contact strips and melt a dot of silver solder to each one. Then I should be able to solder to them easily after that. Hmm- might even lay a dot of silver solder on the contact side as well. I wonder how much better of a connection that would make to a cell terminal- if any better.

The stainless should give a more solid and long lasting contact pressure against the cells- this is what I'm thinking anyway. I usually just use brass strip, but it doesn't really hold up well in that regard. Enough jostling and some of the spring pressure will have been lost.

Stainless seems a better match to the cell terminal metal anyway, in terms of dissimilar metals- though I could be wrong. Any thoughts welcomed.

Paul Alciatore
03-22-2011, 03:45 AM
SS was the first thing I thought of when I saw your title. I imagine it is a good choice. The first thing to avoid in an electrical contact is corrosion and SS should excel there.

As for soldering, you could just use a screw connection.

Evan
03-22-2011, 05:40 AM
Stainless steel has very high electrical resistance. I wouldn't use it for contacts as the electrical resistance is 43 times higher than copper. You are much better off to used tinned spring steel instead. That is what is normally used for contacts. Iron has only 5 times the resistance of copper. Even better is to copper plate the steel and then tin it.

GKman
03-22-2011, 07:54 AM
I got tired of shaking an old flashlight every time I used it and coated the contacts and battery terminals with solder. Works great now. Vibration and wear just exposes more clean solder.

wierdscience
03-22-2011, 08:52 AM
Phosphor Bronze E52100 strip,uses include springs and electrical contacts.

ikdor
03-22-2011, 08:59 AM
The electronics shop sell loose battery contacts to integrate into your own housing. They're too cheap to muck about yourself.

I get mine at Farnell, but state side it's probably Digikey or Mouser

Igor

Evan
03-22-2011, 09:28 AM
As a point of interest, the leads on most components are made from tinned steel.

Peter N
03-22-2011, 03:03 PM
We made literally 100's of 1000's of automotive electrical/electronic connectors - injection moulding over a set of pressed contacts - and 99% of the contacts were made from 1/2 hard Nickel Silver.

This might be a bit exotic or pricey to try and get hold of a sample, but I have some 1/2 hard, 0.5mm/0.020" thick Phosphor Bronze strip. If you're stuck for material (other than stainless) I could cut you off a strip and post it over, providing you don't need a huge amount :D

I should probably also mention that we used to have ALL of the contacts we made plated prior to over-moulding them. Usually gold-plated to reduce oxidation/sulphidation I think. I don't have any of this stuff btw.....

RKW
03-22-2011, 03:45 PM
I have used Keystone before. They have a wide selection.

http://www.keyelco.com/products/sprod01.asp?CategoryID=2