Physics Based Modeling Tools for Next-Generation Lithium Ion Battery Performance and Lifetime

The MDA is developing satellite based systems that could benefit from ongoing developments in advanced materials for lithium ion batteries. Unfortunately, the driving applications for much of the new materials research have less abusive operational cycles than the frequent cycling, and sporadic pulse loads to deep discharge, of MDA satellite applications. Physics based models of battery performance and degradation with these promising material chemistries are desired to help screen candidates that can meet calendar and active life requirements under abusive orbital mission profiles, and to support and improve accelerated life testing. In this STTR program, CFDRC and our partner Washington University at Saint Louis will develop and validate fast, predictive electrochemical models to aid in screening next-generation materials for improved lithium ion battery performance in these applications. The models will include variable lithium diffusivity in the active material particles, improving predictive capabilities for a number of promising materials that undergo solid phase transformations during lithium insertion and removal, and will also incorporate detailed treatment of interfacial film formation and other side reactions that reduce battery capacity and/or discharge rate. During Phase II, we will incorporate additional degradation mechanisms and model parameters will be extracted from and validated against laboratory cycling data.