Groups of freshmen Nanoengineering students from the University of California, San Diego are creating flexible battery packs the size of a credit card, from scratch. The students will test their batteries by attaching an LED bulb and looking for a glow.
This is one of the projects in “NANO 4 / Experience NanoEngineering” – an undergraduate class being taught in a new hands-on educational facility at UC San Diego: EnVision, the Arts and Engineering Maker Studio. NANO 4 is also part of the Experience Engineering Initiative at the Jacobs School of Engineering, which aims to give every engineering and computer science undergraduate student a hands-on or experiential engineering lab course each and every year — starting freshman year.
Nanoengineering professors Sheng Xu and Oscar Vazquez Mena are teaching NANO 4, which involves getting students more deeply involved into some of the fundamental concepts and applications of nanoengineering like energy harvesting and storage, and novel nanomaterials like graphene, exposing them to real problems the society is facing today and also opportunities they can potentially make a notch to the field.
“We want to help expose the students to this side of the field, while giving them a flavor of some cutting-edge research and letting them have fun,” said Xu.
Xu is responsible for mentoring the students for battery and photocatalytic water splitting projects, while Vazquez Mena supervises a project on the two-dimensional material graphene. According to Xu, projects like these have direct connections to current research efforts to expand the function portfolio and improve the device performance. Flexible battery technology, in particular, is of critical importance and value to the burgeoning wearable electronic devices industry as it is an integral part of a self-contained independently working wearable system, for applications in healthcare and consumer electronics.
The students in the course, who are mostly freshmen, are enjoying themselves. Nanoengineering major Deepak Lakshmipathy said that “the professors and TAs are always really helpful – they want you to learn for the class as well as for the future.”
The course is structured to get students engaged with the enabling nanomaterials in these devices. Freshmen nanoengineering majors Jonatan Villegas, Steve Silva, and Emmanuel Antonio worked to do a meticulous job of the first step in the battery fabrication process, carefully painting mixtures of zinc and silver nanoparticles onto flexible foam strips to create the anode and cathode that undergo chemical oxidation and reduction as the battery operates. The trio then placed the strips into a miniature oven to solidify them properly, and inserted them into polymer packages to be sealed with potassium hydroxide solution to form the battery.
As they assemble the battery, students are encouraged to remain mindful of the principles that govern the design: the high surface to volume ratio of the electrodes, and the thin geometry of the overall battery dimension, and the functional composites that improve the device robustness.
Although the class is primarily composed of freshmen looking to get a feel for their selected major field, there are a few upperclassmen enrolled who can reflect on the transformative effect this class has on the nanoengineering course catalog. Senior nanoengineering major Nicole Chiang remarks that “for the freshmen, it’s an amazing way to get involved with the major.”
As the day winds down and the battery packs are ready and charged, a group of students hooks up their batteries to red LED bulbs. A small red glow instantly appears, verifying the batteries’ functionality and eliciting victorious grins from the engineers.