Porous polymer separator layer having a non-uniform cross-sectional thickness for use in a secondary liquid-electrolyte battery

摘要

A porous polymer separator layer that exhibits a non-uniform cross-sectional thickness and a method of making the same are disclosed. The porous polymer separator layer may be made by a process that involves forming a film having a non-uniform cross-sectional thickness similar to that sought to be imparted to the resultant separator layer and deriving the porous polymer separator layer from the film. An electrochemical battery cell for a secondary liquid-electrolyte battery may incorporate the disclosed porous polymer separator layer between a negative electrode and a positive electrode in a way that helps maintain a more evenly distributed current density within the cell.