Please join us for the 14th Annual Stanford Student Energy Lecture Series! During the series, 16 graduate students/postdoctoral scholars, consisting of two speakers per week, will present their energy-related research to an audience of Stanford students, faculty, and staff. 

Koosha Nassiri Nazif 

Talk title: Power anything, anywhere: High-specific-power TMD solar panels

Abstract: A flexible solar cell with a high specific power (power-per-weight) opens unprecedented opportunities in a wide range of industries from wearable electronics to electric vehicles. Ultrathin transition metal dichalcogenides (TMDs) are promising candidates due to their excellent optical and electrical properties. However, engineering challenges have prevented most TMD solar cells from exceeding 2% power conversion efficiency (PCE). In this talk, I explain how we addressed these issues and as a result achieved record PCE of 8% and record specific power of 7 W g−1 in flexible TMD (WSe2) solar cells, the latter on par with established thin-film solar cell technologies. Further design optimization could achieve an additional 10x increase in specific power, providing unprecedented capabilities for wearable electronics and autonomous drones among many others.

Bio: Koosha is a postdoctoral scholar at Stanford developing novel flexible sensors and solar cells for use in a wide range of applications, from wearable electronics to autonomous drones. He received his Ph.D. (2021) in Electrical Engineering and M.S. (2016) in Mechanical Engineering from Stanford, and B.S. (2014) in Mechanical Engineering from Sharif University of Technology.

Yufei Yang    

Talk title: Capacity Recovery by Transient Voltage Pulse in Silicon Anode Batteries

Abstract: In the quest for high-capacity battery electrodes, addressing the significant capacity loss attributed to isolated active materials remains a critical challenge. Here, for the first time, we invent an approach to substantially recover the isolated active materials in silicon electrodes. We employ a voltage pulse to reconnect the isolated Li_xSi particles back to the conductive network. Via a five-second pulse, we achieve >30% of capacity recovery in both Li-Si and Si-LFP batteries. The recovered capacity sustains and replicates through multiple pulses, providing a constant capacity advantage. We validate the recovery mechanism as the movement of the neutral isolated Li_xSi particles under a localized non-uniform electric field, a phenomenon known as dielectrophoresis.

Bio: Yufei Yang is a sixth-year Ph.D. candidate in Materials science and Engineering under the supervision of Prof. Yi Cui. Her research focuses on developing new anode materials for high energy density lithium-ion batteries. She received her Bachelor’s in Engineering at the University of Chinese Academy of Sciences.