Variable-Thickness Press Roll for Uniform Electrode Sheet Stretching

The press roll is designed with non-uniform rubber layer thickness where the thickness varies along the width direction. Specifically, the rubber layer is thinner at the center portion and thicker at the side portions, creating localized differential pressing forces that compensate for the natural non-uniform stretchability of the current collector, thereby achieving uniform stretching without compromising manufacturing simplicity

The physical parameter of the press roll (rubber layer thickness) is intentionally varied along its width to change the pressing characteristics. By adjusting the rubber layer thickness distribution, the press roll delivers different pressing forces at different locations, transforming a simple uniform structure into one that produces controlled non-uniform effects to achieve uniform current collector stretching

The press roll incorporates a rubber layer with spatially varying thickness to provide localized pressing characteristics. This non-uniform thickness distribution ensures that the current collector stretches uniformly across its width, creating proper conditions for subsequent application of the electrode active material layer and protective layer, thereby improving electrode sheet quality without significantly increasing device complexity

The press roll with non-uniform rubber thickness performs preliminary stretching of the current collector before the electrode active material layer and protective layer are applied. This preliminary action ensures the substrate is properly prepared with uniform dimensions and surface characteristics, preventing defects in the final electrode sheet structure