Search NASA⌕ Search

Engineering topics

Pesaran, Ahmad A

Publications and source records attributed to Pesaran, Ahmad A.

Overview of Battery R&D Activities

Five minute PowerPoint presentation giving an overview of Battery R&D activities at NREL for an audience of attended at the 2019 NAATBatt International Annual Meeting & Conference in Litchfield Park, Arizona.

30 DIRECT ENERGY CONVERSION↗

Determining Electrode Tortuosity and Rate Limitations from Experiments and Modeling

CAE models efficiently address 3D large battery performance and safety design. Further work is needed to increase electrochemical model fidelity, reduce expense of parameter ID, and integrate degradation mechanisms, enabling optimization of designs for lifetime. Microstructure models provide deeper insight into predict effective properties of macro-homogeneous models and heterogeneous utilization of electrode degradation. Enabling 10-minute fast charge of BEV200+ requires electrolytes with enhanced transport and low electrode tortuosity.

30 DIRECT ENERGY CONVERSION↗

Efficient Simulation and Abuse Modeling of Mechanical-Electrochemical-Thermal Phenomena in Lithium-Ion Batteries

NREL's Energy Storage team is exploring the effect of mechanical crush of lithium ion cells on their thermal and electrical safety. PHEV cells, fresh as well as ones aged over 8 months under different temperatures, voltage windows, and charging rates, were subjected to destructive physical analysis. Constitutive relationship and failure criteria were developed for the electrodes, separator as well as packaging material. The mechanical models capture well, the various modes of failure across different cell components. Cell level validation is being conducted by Sandia National Laboratories.

25 ENERGY STORAGE↗

Microstructure Characterization and Modeling for Improved Electrode Design

This presentation describes research work led by NREL with team members from Argonne National Laboratory and Texas A&M University in microstructure analysis, modeling and validation under DOE's Computer-Aided Engineering of Batteries (CAEBAT) program. The goal of the project is to close the gaps between CAEBAT models and materials research by creating predictive models that can be used for electrode design.

33 ADVANCED PROPULSION SYSTEMS↗