Scientists from Case Western Reserve University have made a major breakthrough in developing zinc-sulfur rechargeable batteries, offering a safer, more sustainable, and cost-effective alternative to lithium-ion batteries.

These findings, published in the journal Angewandte Chemie, could transform energy storage for a wide range of applications, from renewable energy systems to portable devices.

Lithium-ion batteries power many of today’s technologies, including electric cars and smartphones, but they have drawbacks.

They rely on rare materials, are expensive to produce, and come with safety concerns like fire risks.

Zinc-sulfur batteries, on the other hand, use abundant, inexpensive materials and are safer for the environment.

However, zinc-sulfur batteries have faced challenges, such as zinc corrosion, poor conductivity, and the growth of dendrites—tiny metal spikes that can cause batteries to short-circuit and even catch fire.

These issues have limited their commercial use.

The research team, led by Chase Cao, an assistant professor of mechanical and aerospace engineering at Case School of Engineering, tackled these problems by adding two special chemicals to the battery: propylene glycol methyl ether and zinc-iodide.

These additives improved the battery’s performance in several important ways:

• Increased energy capacity by 20%
• Enhanced conductivity and stability
• Prevented the growth of dangerous zinc dendrites

“These additives don’t just improve efficiency; they also make the batteries safer by addressing the dendrite problem,” explained Guiyin Xu, a professor at Donghua University in Shanghai and co-senior author of the study.

The result is a compact, high-density battery that lasts longer and can be recharged many times without significant wear and tear.

Zinc-sulfur batteries also have a higher energy density than lithium-ion batteries, meaning they can store more energy in smaller sizes. This makes them ideal for portable electronics, renewable energy storage, and even advanced technologies like soft robotics.

Cao’s lab is particularly interested in using these batteries for soft robotics and sensing systems, such as biologically inspired swimming robots that need reliable, long-lasting power for missions in challenging environments.

Beyond robotics, this breakthrough could also benefit space exploration, farming technologies, and efforts to remove dangerous space debris. By improving affordability, safety, and performance, zinc-sulfur batteries could revolutionize energy storage and reduce our reliance on lithium-based technologies.

The study involved collaboration with researchers from Fudan University in Shanghai and The Hong Kong University of Science and Technology, highlighting the global effort to develop more sustainable and innovative energy solutions.