Lithium-ion batteries power almost everything we use today—from smartphones and laptops to electric cars.
But while these batteries have changed how we live, there’s still a lot we don’t fully understand about how they work or how healthy they are over time.
That’s where Shabbir Ahmed, an assistant professor at South Dakota State University, comes in.
His research is focused on making lithium-ion batteries smarter by figuring out more accurate ways to measure how much energy they hold and how well they’re aging.
To understand why this matters, think of your car’s fuel gauge. It tells you how much gas you have left, so you know when to fill up.
Electronic devices like phones and laptops have a similar feature—the battery icon that shows you how much charge is left.
But according to Ahmed, that number you see on your screen is just an estimate, and it’s often not very precise.
That’s because current methods calculate battery life using rough guesses based on voltage and current.
Over time, lithium-ion batteries also lose their ability to hold a charge, something called their “state of health.” For example, you might notice that your phone battery doesn’t last as long after a couple of years.
But most devices don’t show users this important information. Ahmed wants to change that by developing a way to measure both the “state of charge” and the “state of health” more accurately.
This becomes especially important for electric vehicles or aircraft powered by batteries, where incorrect battery readings could affect safety or performance.
Knowing exactly how much power is left and how reliable the battery still is becomes critical in these cases.
To solve this challenge, Ahmed uses sound waves. He places a small sensor on the outside of the battery, which sends an ultrasonic guided wave through it.
This wave interacts with the lithium ions inside the battery, and depending on how those ions are distributed, the wave behaves differently. By analyzing the wave patterns, Ahmed can tell how charged the battery is and how well it’s functioning—without having to take the battery apart.
Ahmed started this work during his postdoctoral research at Stanford University, using his background in ultrasonic wave modeling from his PhD studies at Rensselaer Polytechnic Institute. Now, he’s developing algorithms that could help battery makers, especially in the electric vehicle industry, make safer and more reliable products.
In the future, Ahmed also hopes to bring his expertise into robotics, where energy management is just as crucial. His work could lead to a new generation of smarter, more dependable battery-powered devices.
Source: KSR.
