Purdue University Graduate School
Thesis_Carter.pdf (1.12 MB)

Development of Modified Separator using Vermiculite for Safer Lithium-ion Batteries

Download (1.12 MB)
posted on 2020-11-22, 13:48 authored by Maria N CarterMaria N Carter

Lithium-ion batteries (LIBs) are being used in a variety of applications due to their desirable energy storage characteristics required for modern electronic devices. However, LIBs are prone to thermal runaway due to flammable liquid electrolyte, decomposition of solid electrolyte interphase from anode surfaces, and melting of polypropylene (PP) separators. The separator provides a pathway for Li+ transfer and divides electrodes from electrical contact, avoiding a short circuit, a potentially catastrophic event. A separator that can endure higher temperatures may restrict a cell from causing thermal runaway. This paper demonstrates that vermiculite, a mineral stable over 1,000 °C, could act as a separator lining in LIBs with a lithium ion phosphate (LFP) cathode and lithium anode. Though the standard PP separator shrinks or melts above 130 °C, the vermiculite and binder will continue to provide electronic isolation, allowing the battery to delay a thermal runaway scenario. The vermiculite modified separator demonstrated less exothermic energy release during the thermal runaway, indicating enhanced safety in examined LIBs.


Office of Naval Research: Grant Nos. N00014-18-2397 and N00014-18-1-2397


Degree Type

  • Master of Science in Aeronautics and Astronautics


  • Aeronautics and Astronautics

Campus location

  • West Lafayette

Advisor/Supervisor/Committee Chair

Vikas Tomar

Advisor/Supervisor/Committee co-chair

Vilas G. Pol

Additional Committee Member 2

J. Eric Dietz