Porous Power launches Symmetrix NC2020; new ceramic separator enhances safety, cycle life and performance of lithium-ion batteries
Porous Power Technologies, LLC (PPT) launched Symmetrix NC2020, a new ceramic battery separator designed to improve significantly thermal stability and safety of large-format lithium-ion batteries. Applications include batteries for electric vehicles, flat-cell consumer electronics, utility-grade energy storage, and other high-power or high-energy applications.
The battery separator is a vital component in the safety/cycle life/performance equation of batteries; Symmetrix NC2020, developed by PPT in partnership with Ahlstrom, delivers sizable improvements in all three areas, particularly safety, the company said. Ahlstrom took a 49.5% stake in Porous Power Technologies in 2011.
Use of ceramics in separators is not new. However, most manufacturers apply a ceramic coating on conventional polyolefin separators. A coating can impede ion flow through the separator, reducing battery cycle life and performance.—John Shelburne, PPT’s Director of Research and Development
Further, it can crack or flake off, potentially contaminating the cell.
In contrast, Symmetrix NC2020’s ceramic particles are blended with PVDF—a higher grade polymer intended to last for many years—to form a flexible, ceramic-rich microporous membrane. Ions flow freely though the open pore structure, enabling cells with good power over broad temperature ranges.
The sponge-like membrane conforms to the electrode surface to prevent dead spots and ensure reliable performance, even as electrodes expand and contract over many cycles.
Other benefits of Symmetrix NC2020 lithium-ion battery separators include:
Superior thermal and chemical stability with less long-term cell degradation.
Reduced internal resistance enables freer ion flow and minimizes heat generation.
Oxidation resistance and compatibility with high-voltage chemistries.
Fast and thorough electrolyte wicking; more absorbent than traditional separators.
Eliminates dry spots, optimizing cell capacity and battery life.
The ability to laminate securely to electrodes, which simplifies manufacturing and boosts production yields.
Superior conformability eliminates voids and lowers interfacial impedance.