­ 'Plug-and-Play' Biobatteries Generate Power for Weeks

One of the most challenging things about implementing the Internet of Things (IoT) is powering the sensors. We need measurements of almost every metric in a system so that the processing elements can understand what is happening and provide the most accurate output. That means that there will be small sensors embedded throughout each system to measure its performance, as well as the environment around it. Many of these sensors will be in remote locations, far from the mains power. They will be difficult, and sometimes impossible to reach for maintenance and battery changes. Keeping them powered is vital to the success of the system.

There has been some great research done on tiny solid-state batteries, but they are still quite a way to be truly commercialized. Other small cell batteries have a lifespan that can be measured in hours. In the meantime, researchers are looking at new ways to power IoT systems. One of these researchers is Professor Seokheun “Sean” Choi — a faculty member in the Department of Electrical and Computer Engineering at Binghamton University’s Thomas J. Watson College of Engineering and Applied Science. Choi has working for years on biobatteries, which generate electricity through bacterial interaction. In his latest piece of work, Choi has developed a “plug-and-play” biobattery that can last for weeks at a time and has the ability to be stacked to improve output voltage and current, depending on how the cells are arranged.

The new study has been published in the Journal of Power Sources. In the paper, Choi and his fellow researchers described a “plug-and-play” biobattery that has the ability to last for weeks at a time. Co-authors on the research are from Choi’s Bioelectronics and Microsystems Lab: current PhD student Anwar Elhadad, and Lin Liu, PhD ’20 (now an assistant professor at Seattle Pacific University).

The batteries that had previously been developed by Choi functioned by using two bacteria that interacted to generate the power needed. His latest iteration uses three bacteria in separate vertical chambers: “A photosynthetic bacteria generates organic food that will be used as a nutrient for the other bacterial cells beneath. At the bottom is the electricity-producing bacteria, and the middle bacteria will generate some chemicals to improve the electron transfer.”

Vhoi described the need for a new type of battery by saying, “with artificial intelligence, we are going to have an enormous number of smart, standalone, always-on devices on extremely small platforms. How do you power these miniaturized devices? The most challenging applications will be the devices deployed in unattended environments. We cannot go there to replace the batteries, so we need miniaturized energy harvesters”

Choi compares these new biobatteries — which measure 3 centimeters by 3 centimeters square — to Lego bricks that can be combined and reconfigured in a variety of ways depending on the electrical output that a sensor or device needs. He is hoping to research the battery further to create a package that can float on water and perform self-healing to automatically repair damage incurred in harsh environments. He also wants to shrink the batteries down to a tiny size. He explained, “we call this ‘smart dust,’ and a couple of bacterial cells can generate power that will be enough to operate it. Then we can sprinkle it around where we need to.”

The study was supported by a $510,000 grant from the Office of Naval Research

https://discovere.binghamton.edu/