Research at Stanford University has created a mathematical model for the design of new materials for storing energy that could lead to increased performance of high-powered electrical storage devices, such as car batteries, according to a report on the school’s website.
This research models new materials for energy storage. (Wikimedia Commons)
Stanford professor Daniel Tartakovsky believes that his model can save time for other scientists, who rely on the trial-and-error method for testing, to create materials for capacitors and batteries that are smaller but last longer.
The article explained, “Tartakovsky hopes the new materials developed through this model will improve supercapacitors, a type of next-generation energy storage that could replace rechargeable batteries in high-tech devices like cellphones and electric vehicles.
“Supercapacitors combine the best of what is currently available for energy storage – batteries, which hold a lot of energy but charge slowly, and capacitors, which charge quickly but hold little energy. The materials must be able to withstand both high power and high energy to avoid breaking, exploding or catching fire.”
The key is developing better nanoporous materials, which had previously been done by a painstaking process that required extensive planning, labor, and experimentation with no guarantee of success. This new model could take some of the guesswork out of the process and speed up developments in this area.
The research was recently published in Applied Physics Letters. The abstract explained:
“Unique macroscopic properties of nanoporous metamaterials stem from their microscopic structure. Optimal design of such materials is facilitated by mapping a material's pore-network topology onto its macroscopic characteristics.
“This is in contrast to both trial-and-error experimental design and design based on empirical relations between macroscopic properties, such as the often-used Bruggeman formula that relates a material's effective diffusion coefficient to its porosity. We use homogenization to construct such a map in the context of materials design that maximizes energy/power density performance in electrochemical devices.
“For example, effective diffusion coefficients and specific surface area, key macroscopic characteristics of ion transport in a hierarchical nanoporous material, are expressed in terms of the material's pore structure and, equally important, ion concentrations in the electrolyte and externally applied electric potential.
“Using these microscopic characteristics as decision variables, we optimize the macroscopic properties for two two-dimensional material-assembly templates and several operating conditions. The latter affect the material's performance through formation of an electrical double layer at the fluid-solid interfaces, which restricts the pore space available for ion transport.”