From electric vehicles to power tools, traditional lithium-ion batteries are becoming an essential element in everyday work and life, offering fast charging and high energy storage. However, these batteries rely on liquid electrolytes, which pose serious safety risks—they can catch fire if damaged or overheated. For electrical contractors working with energy-intensive devices, battery reliability and safety are paramount.

Solid-state batteries are a viable alternative, but present greater manufacturing challenges compared to traditional lithium-ion batteries. Their production demands highly precise fabrication techniques to achieve seamless solid-solid interfaces between components, ensuring optimal performance and reliability. Maintaining this level of precision is critical for enhancing battery efficiency, longevity and overall safety.

Researchers at the University of Missouri are exploring a safer, more energy-efficient solid-state battery. The research team is developing a way to replace liquid electrolytes with solid materials, reducing the risk of fire while improving performance.

Although solid-state batteries promise greater efficiency, safety and longevity, they face a major roadblock. When the solid electrolyte meets the cathode, a chemical reaction forms an interphase layer about 100 nanometers thick, which is very thin—1,000 times smaller than the width of a human hair, in fact.

According to the research team, this layer blocks lithium ions and electrons from moving easily, increases resistance and hurts battery performance. This has challenged scientists for many years and explains why solid-state batteries have remained largely experimental—until now.

The researchers tackled the problem by investigating its root cause using four-dimensional scanning transmission electron microscopy. This advanced technique allowed them to examine the battery’s atomic structure without disassembling it—a game-changer for the field.

By analyzing the chemical reactions occurring inside the battery, they determined that the interphase layer was the primary obstacle to battery efficiency, which prompted them to direct their focus on preventing this unwanted reaction from occurring in the first place.

The University of Missouri team specializes in thin-films created using oxidative molecular layer deposition, a vapor-phase process that could be the key to solid-state battery advancement. They are now testing whether these nanotechnology thin films can act as protective coatings to prevent the solid electrolyte and cathode from reacting.

The team was further challenged as the coatings need to be thin enough to prevent reactions but not so thick that they block lithium-ion flow. Ideally, the best performance comes when keeping the solid electrolyte and cathode materials working together without sacrificing performance.

This nanotechnology-driven approach could be a game-changer for battery safety and efficiency, making solid-state batteries more viable for widespread use in electrical applications.

For electrical contractors, the development of solid-state batteries can enhance job-site safety by eliminating the risk of thermal runaway and fires. This technology also improves battery longevity, reducing replacement costs for power tools and equipment, and delivers higher energy efficiency, ensuring longer run times and faster charging for devices.