Nanofilled polymers for energy: Li ion batteries

Janna K. Maranas, Pennsylvania State Univ University Park, DMR 0907128

Laptop computers, cell phones, and electric vehicles or plug in hybrids rely on Li ion batteries as a portable power source. These devices have liquid components, but safety, end of life disposal and batteries that run longer or deliver more power would benefit from replacement of these components with polymers. Li ion batteries require movement of Li ions through the device, and such movement is slower in solids like polymers than in liquids. It is thus important to find ways to increase Li ion movement [conductivity] in polymers. One way to do this [and the subject of our DMR-Polymers program research] is to add fillers with nanoscale dimensions.

A highlight from 2012 is our finding that mixtures of Li salts with the polymer PEO have a “sweet spot” in composition. At this special composition [called the eutectic] not only is the effect of the nanofiller maximized, the chemistry of the surface doesn’t matter. This is important because some possible explanations for this observation could lead to significant gains when the shape of the nanofiller is changed.

Top: uses of Li batteries for portable power. Bottom: The increase in Li mobility by adding nanoparticles is largest and most general at the “sweet” composition [eutectic].

Both graduate and undergraduate programs in science and engineering have only a small focus on training for communicating scientific results. However, future jobs in industry or academia require these skills; estimates from recent PSU graduates in Chemical Engineering center around 70% of work time spent communicating.

For the past several years, have focused on providing this training for our students. Highlights from the past year include a writing workshop offered to first year graduate students, and training undergraduates in speaking through honors options to CHE courses. Both emphasized communicating to non-scientists.

Communicating effectively in science

Janna K. Maranas, Pennsylvania State Univ University Park, DMR 0907128

Penn State graduate students participating in the 2012 summer writing workshop.