Fundamental understanding of the interrelationship of battery separator structures and properties with their electrical and physical performance

Despite the relatively long history of the development and production battery separators, there are still significant opportunities for further investigation towards optimizing separator performance.  For instance, it has been a challenging question to the battery separator industry on how to attain both low electrical resistance and high oxidation resistance simultaneously.  Significant efforts have been made over the years to find the answer.  In reality, these endeavours have only been partially successful in that one property was improved to the detriment of the other.  Microporous have investigated the above problem by using fundamental knowledge of the interrelationship of composite structure to properties of the separators.  Because the separators are composites of multiple constituents such as ultra-high molecular weight polyethylene, silica, oil, rubber, etc., their properties are not a linear function governed by a single factor, but rather by a multi-variable question affected by many factors, e.g., pore characteristics, polymer rheology and surface chemistry. Through a systematic approach, it was found that the chemical, electrical and mechanical properties of separators are largely affected by their microstructures.  The variables include the composition of the constituents, processing conditions, etc.  This presentation introduces a new separator product — CellForce® HT — of which the microstructure of the separator is engineered to accomplish low electrical resistance as well as enhanced oxidation resistance.  This product is the most recent outcome of  continuous efforts toward innovative battery separators, which are designed to exceed the market requirements of automotive EFB applications.


Dr Sunho Choi Technical Manager, Microporous, United States

Sunho Choi is a technical manager within the R&D department of Microporous LLC, and is in charge of imparting fundamental materials engineering and membrane process expertise to stage gate product and process development during the design and implementation phase of new projects. Before he joined Microporous LLC, he previously worked at Northeastern University as Assistant Professor, after doing his Ph.D. at the University of Minnesota and the postdoc at Georgia Tech. He is currently enhancing and developing further Microporous’ portfolio of technical separator products using his fundamental understanding of membrane technology and 17 years of R&D experience,