Even though we know where ExxonMobil's priorities lie that doesn't mean they want to get left out of the lithium ion battery land rush. Tonen Chemical is part of ExxonMobil Chemical and they've now started commercial production of microporous films that are used as separators between the electrodes of lithium batteries. They've developed a new manufacturing process for making the polymer films that have higher melting temperatures improving the thermal safety of the batteries. Of course,even when working on battery components, ExxonMobil still gets to use petroleum to produce the polyolefin films.
[Source: ExxonMobil Chemicals]