Microstructure Applications for Battery Design

NREL's Computer-Aided Engineering for Electric Drive Vehicle Batteries (CAEBAT) work includes simulating physics at the electrode microstructure level and created a virtual design tool for battery electrodes and microstructure.
Computer-simulated image of three cubes that show materials of an electrode at the microstructure level. The image shows that the composite electrode at 50  m is made up of active material and inert material, which includes carbon black and PVDF binder at 200 nm.

Simulation of constituent materials that make up a composite electrode at the microstructure level. Image from Texas A&M University

CAEBAT microstructure efforts focus on:

  • Developing microstructure modeling tools to improve computer-aided design of battery electrodes
  • Formulating models that are predictive and thereby reduce the need to build and evaluate prototype electrodes for battery design
  • Improving the knowledge of battery performance and degradation physics, both of which rely on electrode recipe, material selection, and other key battery design decisions
  • Validating models for electrodes that vary in thickness, chemistry, and manufacturing conditions.
A computer-generated image of a particle at the electrode microstructure level, showing the distribution of lithium in an active particle during electrochemical discharge.

Distribution of lithium in an active material particle during electrochemical discharge.

Researchers at NREL and Texas A&M University have prototyped software for computer-aided engineering of next-generation battery electrodes, including NREL's finite-element code to simulate battery electrochemistry on microstructure geometry. The models are being validated by electrode samples, electrochemical measurements, and mapping microstructure 3-D geometry provided by Argonne National Laboratory's Advanced Photon Source.

In addition to tomographic measurements of microstructure geometry, Texas A&M developed a computer-aided tool that can generate realistic microstructure geometries. This allows designers to develop simulated predictions of a battery's performance without building an electrode and mapping its geometry beforehand.

NREL scientists carry out computationally complex simulations using NREL's high-performance computer, Peregrine. Yet for even faster simulation, which can be carried out on an everyday laptop, the NREL and Texas A&M team are developing mesoscale models that capture the effects of electrode composition on battery electrochemical transportation properties, such as conductivity and diffusivity. The mesoscale simulations support the design of battery cells, modules, and packs using other CAEBAT project tools.


Kandler Smith