Research at Stanford University
I worked with Prof. William Chueh on making lithium-ion batteries last longer and charge faster. My work aimed to combine bottom-up and top-down experiments to study degradation in carbon anodes.
My primary projects included:
- Characterizing the growth of the solid-electrolyte interphase (SEI). SEI growth is a major degradation mode in lithium-ion batteries. This process is similar to iron oxidation (i.e. rusting); a surface layer forms that both consumes material (lithium or iron) and also prevents further growth (termed self-passivation). We characterized SEI growth via electrochemical and microscopic techniques. Notably, we discovered that the growth of this layer occurs much faster during battery charging than battery discharging.
- Optimizating fast-charging protocols for commercial batteries. Fast charging is important for widespread adaptation of electric vehicles, but it generally reduces battery lifetime. Multistep charging protocols can achieve both low charging time and high lifetime, but this optimization problem is expensive due to the long testing time and large number of experiments required. In our work, we first developed machine learning models to predict the final lifetime (1000s of cycles) using data from the first 100 cycles. Then, we used optimal experimental design to efficiently find the highest-lifetime charging protocols (work in review). By reducing the number of cycles required per experiment (using early prediction) and the total number of experiments (using optimal experimental design), we can optimize previously intractible battery challenges in a fraction of the time.
Research at University of Delaware
I worked with Dr. Joshua Zide for three years on a novel application of thermoelectric materials. Thermoelectrics are often considered for waste-heat recovery applications, exploiting a steady-state spatial temperature gradient to generate electricity. We investigated thermoelectric power generation in dynamic temperature environments, or environments with either cyclical or random temperature variations with respect to time. This work is detailed in Bomberger et al and Attia et al.
Lastly, I interned with DuPont Engineering Technologies in the Heat, Mass, and Momentum Transfer group for a summer. I worked on a variety of chemical engineering problems, including water absorption, heat exchanger design, and solid-liquid mixing.