Jelly Roll Battery Cell Tab Layout to Prevent Pseudo Soldering

The patent segments the tabs into two distinct groups: first tabs that extend beyond the winding portion and second tabs that are positioned within the winding portion. This segmentation allows different welding approaches for different tab types, ensuring reliable welding for both while maintaining high capacity. The first tabs can be welded using conventional ultrasonic welding, while the second tabs are designed to prevent pseudo soldering by being positioned where they don't interfere with the welding process of other tabs.

The patent utilizes the spatial dimension by positioning second tabs within the winding portion at specific radial distances from the center of the battery cell. This dimensional arrangement ensures that tabs are distributed in a way that allows ultrasonic vibration energy to penetrate effectively while maintaining adequate flow area. The radial positioning creates a three-dimensional tab arrangement that resolves the contradiction between quantity and welding quality.

The patent applies local quality by differentiating the treatment and positioning of first tabs versus second tabs. First tabs extend beyond the winding portion and are welded in one manner, while second tabs are positioned within the winding portion at specific radial distances and welded differently. This localized differentiation simplifies the overall design by creating clear zones with specific functions, reducing the complexity that would arise from treating all tabs uniformly.

The patent employs partial action by not requiring all tabs to extend beyond the winding portion. Instead, only the first tabs extend beyond, while the second tabs are positioned within the winding portion. This partial approach optimizes the balance between flow area (achieved by first tabs) and welding reliability (achieved by second tabs positioned within the winding), avoiding the excessive complexity that would result from all tabs extending beyond the winding.