Originally Posted by John Stranahan

Thought this might be a good thread to report these tests. I tested the voltage drop accross a battery bar while the 6 cell pack was being discharged at 20 amps. The more the voltage drops, the less voltage gets to your motor. Bars are pretty good these days so we are not talking big losses, but as part of a resistance lowering effort for stock motor racing in the entire car, every little bit helps.

Deans Bars 2% Silver Solder (the rest lead tin alloy) - 2.5 mV per bar

Deans Bars Deans Silver Solder (3% silver, I believe) - 1.7 mV per bar
This solder worked great for bars. I use flux like bigdogracing, but a tiny drop of clear liquid flux (HCl,ZnCl2) only on battery bars. Residue washes off easily with alcohol. a 900F -1000 F tip is the key to a good fast soldering job on these heavy conductors. I found that this solder has too much built in flux for lead wires. you tend to stiffen about 1/2 inch of lead wire under the insulation. This eventually causes a hidden failure of the wire. Use the Novak solder instead.

Promatch Bars (these are a little wider than Deans, but a little thinner. Slightly more crosssectional area than Deans. They fit better through the JRXS) 4% Silver solder (the rest lead tin alloy). 1.2 mV, About a 50 % improvement over 2% silver solder and Deans Bars. I don't have a national supplier for this solder, but its from the far east.

I never had a Deans bar loose its plating. I do sand the batteries. I get very reproducible voltage drops from one bar to the next without trying to make the Deans bars flat, although solder is not as good a conductor as the bar so the thinner the solder layer the better.

NiMH, I believe use an alkiline electrolyte solution. It is already wet inside. No need to worry about condensation. LiPo's have an organic solvent inside instead;no water inside. No way for condesation to occur either.

Plating type is just Hype. I like the zinc plating on Deans bars, because it has never failed me by peeling off. Should be stuck to the bar as good as solder if it is plated correctly.

If an object (like a ball or a wire) is charged by static electricity (an excess of charge) the charge tends to repel itself and collects on the surface. This does not carry over to conduction in a wire where there is a relatively slow flow of electrons and no exess charge is built up. This sea of electrons is in the entire conductor not just on the surface.