2013 R&D 100 Winner
SYMMETRIX HPX-F Polymer-Ceramic Composite SeparatorLithium-ion battery separators prevent the anode and cathode layers from contacting each other, allowing cell potential to be maintained and safe operation of the battery. The SYMMETRIX HPX-F polymer-ceramic composite separator, developed by Porous Power Technologies and Oak Ridge National Laboratory, achieves this functionality while improving safety over conventional polyolefin membranes. It utilizes three materials to form a novel microstructure—a non-woven polyethylene terephthalate (PET) polymer-fiber backbone, a nanodispersed ceramic filler and a polyvinylidene fluoride (PVDF) polymer binder—to separate the anode and cathode layers. During cell assembly, it is filled with a lithium-ion-conducting electrolyte that consists of low-molecular-weight organic carbonate solvents and a lithium salt. The separator is a passive, mesoporous component that must stay intact to maintain cell voltage and prevent electrical shorting. It's performance advantages include: excellent retention of mechanical strength when subjected to compression fatigue; improved resistance to internal short circuiting when exposed to external force; a doubling of time to thermal runaway during accelerated rate calorimeter and a microstructure that improves long-term cell cycling performance by 7 to 8%.

Polymer-ceramic composite separator

Porous Power Technologies
Oak Ridge National Laboratory

Development Team

Oak Ridge National Laboratory's SYMMETRIX HPX-F polymer-ceramic composite separator development team. Back row (l-r): Jianlin Li, Amit Shyam, Harry Meyer III, Ralph Dinwiddie, Wally Porter, Cristian Contescu, Edgar Lara-Curzio, Hsin Wang. Front row (l-r): L. Curt Maxey, Claus Daniel, David Wood III, Beth Armstrong.


Porous Power Technologies' SYMMETRIX HPX-F polymer-ceramic composite separator development team. Back row (l-r): Yeong Kim, David Frank, Michael Pender, Shawn Zhao, Bernard Perry, John Shelburne. Middle row (l-r): Kevin McClellan, Jamie Owens, Ann Edwards, Kirby Beard, Trevor Beard. Front row (l-r): Jay Forlino, Gebrehiwot Zewdea, Calahan Kirkner, Eric Qin.


The SYMMETRIX HPX-F polymer-ceramic composite separator Development Team
Kirby Beard, Principal Developer, Porous Power Technologies
David Wood III, Principal Developer, Oak Ridge National Laboratory
Beth Armstrong, Oak Ridge National Laboratory
Cristian Contescu, Oak Ridge National Laboratory
Claus Daniel, Oak Ridge National Laboratory
Ralph Dinwiddie, Oak Ridge National Laboratory
Ann Edwards, Porous Power Technologies
Jane Howe, Oak Ridge National Laboratory
Edgar Lara-Curzio, Oak Ridge National Laboratory
Jianlin Li, Oak Ridge National Laboratory
L. Curt Maxey, Oak Ridge National Laboratory
Harry Meyer III, Oak Ridge National Laboratory
Wallace Porter, Oak Ridge National Laboratory
Amit Shyam, Oak Ridge National Laboratory
Rosa Trejo, Oak Ridge National Laboratory
Hsin Wang, Oak Ridge National Laboratory