Featuring improved thermal stability and lower shutdown temperature for a higher safety margin, the developmental grades add to the company’s battery separator film portfolio that includes the V-series separator films introduced in 2007.

Based on the same advanced co-extrusion technology platform and proprietary wet bi-orientation manufacturing process as V-series separator films, the developmental grades can help prevent thermal runaway in batteries while providing LIB designers more flexibility in selecting electrode systems and formats in battery designs to improve power and capacity density.

Each of the new developmental grades offers safety-margin enhancements. Developmental grade 1 extends thermal stability with an improvement in transverse direction shrinkage to 8%, at 130 ºC for 30 minutes, from 35.5% in previous-generation separator films.

Developmental grade 2 has a significantly improved shutdown temperature of 128 °C, compared to 134 °C for a standard V series grade, and maintains a longer insulation period with higher meltdown functionality.

ExxonMobil Chemical currently manufactures battery separator films in Nasu, Japan, and is building a manufacturing facility in Gumi, Korea, to accommodate additional demand and serve global customers reliably and efficiently. The new manufacturing plant will be completed in 2010.