As a chemist, Dr. Yangju Lin tackles the big picture by looking at its smallest pieces. His research combines polymer science with device applications, offering molecular solutions that can help address practical challenges, such as sustainable energy.
“If you dig down into any material, it’s just molecules,” says Lin. “For me, molecular engineering feels like seeing the truth of the materials around us. When I think about societal challenges or real-life problems, I look at them through molecules.” This gives him a unique perspective on battery power, in particular.
Lin develops functional and smart plastics that are chemically engineered to respond to force, light, and other chemical signals. These functional plastics might, for example, change colour or texture when force is applied. They have many applications, batteries among them.
“People don’t often think much about the polymeric components in batteries because they are small, but they are critical to efficient battery performance,” says Lin.
Lin is currently focused on the plastic membrane, or polymer electrolyte, between positive and negative electrodes. This membrane ensures the battery won’t short-circuit and catch fire, but it also needs to allow ions to move back and forth. Functional polymers can do this more efficiently, while also improving overall battery performance.
Mechanical durability of the membrane is another factor that makes batteries more sustainable. A more durable membrane can withstand internal dynamic stress within batteries, mitigating mechanically induced side effects and improving battery lifespan.
Lin’s research also has the potential to lessen the environmental impact of batteries in another important way. Many of the polymers currently used as binders in electrodes are fluorinated. Fluorinated polymers are often referred to as “forever chemicals” because of their extreme persistence. That, alongside the toxic by-products released throughout their life cycle, makes them an environmental concern.
“One thing we are looking at is designing better, greener alternatives to fluorinated polymers,” says Lin.
Batteries that are more efficient, durable, and environmentally friendly are key to sustainable and reliable energy and have applications from electric vehicles to renewable energy systems. Lin’s research shows how small changes can have big impacts.