Wedoany.com Report on Mar 4th, Research institutions from India, Australia, and the UK recently collaborated, utilizing a 270-year-old physics phenomenon—the Leidenfrost effect—to construct an atomic highway within the cathode of a sodium-ion battery, significantly improving battery performance.
This research was conducted by scientists from the Indian Institute of Science Education and Research (IISER) Bhopal and the Indian Institute of Technology Gandhinagar (IITGN), in collaboration with teams from the University of Southern Queensland, Australia, and Swansea University, UK. They developed a novel cathode material that enables rapid, repeated sodium-ion movement while maintaining structural stability.
The transition to a clean energy economy relies on lithium-ion batteries to store renewable energy. However, lithium extraction is complex, costly, and environmentally taxing. In contrast, sodium is abundant and cheap, but its larger ions can easily clog the cathode, leading to degraded battery performance. Therefore, finding suitable cathode materials is a key challenge.
The researchers used Na₄Fe₃(PO₄)₂(P₂O₇), an iron-based phosphate-pyrophosphate mixture, to construct the cathode. It naturally forms a stable three-dimensional tunnel-like structure that facilitates sodium-ion flow. However, pure iron-based materials suffer from conductivity and energy capacity issues. To address this, the team added indium to the mixture. Replacing just 1% of the iron atoms with indium increased atomic spacing, making sodium-ion movement easier and enhancing conductivity.
"We decided to build the right cathode infrastructure, an atomic highway, so sodium ions could travel fast!" explained Subhajit Singha, a PhD student at IISER Bhopal involved in the work.
Beyond material improvement, the researchers also optimized the manufacturing process by applying the Leidenfrost effect. This effect, discovered 270 years ago by German physician Johann Gottlob Leidenfrost, describes how water droplets glide on an overheated surface due to a vapor layer. The team sprayed the cathode material onto a metal surface, triggering instantaneous evaporation, which produced a porous particle powder. This sponge-like structure absorbs electrolyte, enabling smoother sodium-ion transfer.
This method avoids the use of traditional furnaces, making the manufacturing process more environmentally friendly and ensuring the cathode's crystal structure remains intact over thousands of cycles. In contrast, standard lithium-ion batteries typically last only a few hundred cycles.
"The optimized cathode material demonstrated a high energy density of approximately 359 Wh kg⁻¹, along with remarkable durability and stable performance over more than 10,000 charge-discharge cycles," said Raghavan Ranganathan, an associate professor at IITGN, in a press release.
The research findings have been published in the journal Small, offering a new approach for developing large-scale energy storage infrastructure. It holds promise for reducing battery costs using inexpensive sodium materials and advancing green energy applications.
