Originally Posted by: RobSm... Why wouldn't copper foil be used there as well? Is it a cost consideration?
Wouldn't two different metals in contact produce some sort of potential difference? If so is it neglible?

I just can't see why the copper foil wouldn't be used everywhere.

Any suggestions?

[font=trebuchet ms]Placing copper and aluminum in contact with each other creates a small battery. This galvanic condition will cause corrosion at the junction. Replace the aluminum with copper foil (since it's the easier change to make).[/font]