Celgard Inc.

Barry J Summey

Kristoffer K Stokes

Xiaomin Zhang

Kang Karen Xiao

Changqing Wang Adams

Daniel R Alexander

Brian R Stepp

Shante P Williams

William John Mason

Robert Moran

Jeffrey Gordon Poley

Andrew Edward Voss

Douglas George Robertson

Novel or improved microporous single or multilayer battery separator membranes, separators, batteries including such membranes or separators, methods of making such membranes, separators, and/or batteries, and/or methods of using such membranes, separators and/or batteries are provided. In accordance with at least certain embodiments, a multilayer dry process polyethylene/polypropylene/polyethylene microporous separator which is manufactured using the inventive process which includes machine direction stretching followed by transverse direction stretching and a subsequent calendering step as a means to reduce the thickness of the multilayer microporous membrane, to reduce the percent porosity of the multilayer microporous membrane in a controlled manner and/or to improve transverse direction tensile strength. In a very particular embodiment, the inventive process produces a thin multilayer microporous membrane that is easily coated with polymeric-ceramic coatings, has excellent mechanical strength properties due to its polypropylene layer or layers and a thermal shutdown function due to its polyethylene layer or layers. The ratio of the thickness of the polypropylene and polyethylene layers in the inventive multilayer microporous membrane can be tailored to balance mechanical strength and thermal shutdown properties.

Membranes, calendered microporous membranes, battery separators, and related methods

Growing community of inventors

Lake Wylie, SC, United States of America

Barry J Summey