The conditions for copper corrosion were investigated with regard to its use as the negative grid material in high performance lead-acid batteries with gelled electrolyte. The experiments on copper sheets show that only under very extreme conditions, when there is a thin electrolyte film on the surface and no lead coating over a distance of more than about 3 mm, copper dissolution can occur. In this case, substantial potential shifts in the thin electrolyte film, resulting in a much more positive potential at that part of the electrode, were measured. With a properly lead-coated copper grid there will be virtually no copper corrosion even under starved electrolyte conditions. In additional experiments on lugs of conventional negative lead-calcium grids, similar potential shifts in the positive direction, although much more moderate, were found when there was a thin electrolyte film only on the surface. This result makes a contribution to the better understanding of the mechanism of the corrosion attack at the negative lug/group strap area of valve-regulated lead-acid batteries, which has been observed occasionally.