A team of scientists in South Korea has discovered a way to make all-solid-state batteries safer and more powerful using inexpensive materials. Instead of adding costly metals, they redesigned the battery’s internal structure to help lithium ions move faster. This simple structural tweak boosted performance by up to four times. The work points to cheaper, safer batteries for phones, electric vehicles and beyond.
Batteries play a critical role in everyday life, from powering smartphones to enabling electric vehicles. Despite their importance, today’s batteries still come with major drawbacks, including high costs and the risk of fires or explosions. All-solid-state batteries have long been viewed as a safer alternative, but progress has been slowed by the challenge of balancing safety, performance and affordability. The new research has shown that battery performance can be significantly improved through smart structural design alone, without relying on expensive metals.
Advertisement
Together, the researchers developed a new design approach for key all-solid-state battery materials that uses inexpensive raw ingredients while maintaining strong performance and a lower risk of fire or explosion.
Traditional lithium-ion batteries depend on a liquid electrolyte that allows lithium ions to move between electrodes. All-solid-state batteries replace this liquid with a solid electrolyte, which greatly improves safety. However, lithium ions move more slowly through solids, and past efforts to speed them up often depended on costly metals or complicated manufacturing techniques.
Advertisement
To solve this problem, the researchers focused on improving how lithium ions travel through solid electrolytes. Their strategy centred on the use of ‘divalent anions’ such as oxygen and sulphur. These elements influence the crystal structure of the electrolyte by becoming part of its fundamental framework, which can change how ions move inside the material.
The team applied this idea to low-cost zirconium-based halide solid electrolytes. By carefully introducing divalent anions, they were able to precisely adjust the internal structure of the material. This approach, known as the Framework Regulation Mechanism, expands the pathways available to lithium ions and reduces the energy needed for them to move. As a result, lithium ions can travel more quickly and efficiently through the solid material.
Advertisement
Tests showed that adding oxygen or sulphur to the electrolyte increased lithium-ion mobility by two to four times compared with conventional zirconium-based electrolytes. This improvement indicates that solid-state batteries can reach performance levels suitable for real-world use without relying on expensive materials.
‘Through this research, we have presented a design principle that can simultaneously improve the cost and performance of all-solid-state batteries using cheap raw materials,’ said Professor Dong-Hwa Seo from the Department of Materials Science and Engineering at the Korea Advanced Institute of Science and Technology. ‘Its potential for industrial application is very high.’
The research has been published in Nature Communications.