PhD Project by Swetha V. Kanakkottu

Project Title: Fabrication of On-chip microsupercapacitors for electrochemical energy storage
Group: Biomaterial Microsystems
Supervisor: Stephan Sylvest Keller

Project Description
With the rapid development and advancement of nanotechnology, there is a development trend towards low-power integrated circuits such as microprocessors or wireless communication chips. These types of systems are designed to operate without connection to the power grid. Li-ion batteries are most dedicated technologies to supply power to these systems. But due to the short life span, Incapability to charge and discharge at high rate and high resistance, On-chip micro batteries do not fulfill the requirements demanded by the autonomous systems. But when come to these applications, supercapacitors can fill the voids that is created by Li-ion batteries. On-chip microsupercapacitors are nothing but an EDLC or puedocapacitors miniaturized to microscopic level and fabricated on the chip, so that the system can be easily integrated with existing micro electronic systems.

Micro supercapacitors meet the micro power demands and have the capability to replace micro batteries in electrical storage and harvesting systems where high rate of charging and discharging required in very short times.

Various technologies have been reported for the miniaturization and fabrication of On-chip micro supercapacitors such as photolithography, Inkjet printing, screen printing, selective wetting induced fabrication, microfluid etching assisted fabrication and laser irradiation assisted fabrication etc.
But these technologies are either expensive, time consuming or required high sophisticated environment like clean room set up. Thus, an efficient, easy and cost-effective fabrication method for high energy density on-chip microsupercapacitors is high in demand.
The main aim of this PhD project is to design and fabricate On-Chip microsupercapacitor with a low cost and simple DLP 3D printing technology with higher energy density.

Perspective
It was observed that 3D printing is a promising technology to fulfill all the requirements needed for On-Chip microsupercapacitor fabrication. Thus, a detailed study of On-Chip microsupercapacitor fabrication by DLP 3D printing technology needs to be investigated systematically. This allows for commercialization and mass production of On-chip microsupercapacitors.

The hypothesis of this project is that the direct 3D printing of optimized interdigitated structure of photocurable resin with pore generating additives on silica substrate, followed by optimized pyrolysis process will allow for the fabrication of 3D carbon microelectrodes on the substrate with higher material loading on the same footprint area.