A team of materials scientists in China has developed a breakthrough design for sodium-ion battery anodes that could significantly enhance energy storage capabilities, according to a recent report titled “Core-shell anodes boost energy storage in sodium-ion batteries,” published by Tech Xplore. By engineering a novel core-shell structure, the researchers have successfully addressed long-standing challenges in the performance and stability of sodium-ion batteries, positioning the technology as a more viable alternative to current lithium-ion systems.
The researchers, based at China’s Shenzhen Institute of Advanced Technology, focused on improving hard carbon—a common but imperfect anode material for sodium-ion batteries. While hard carbon is attractive due to its abundance and affordability, it suffers from limited capacity and poor structural integrity under repeated cycling. The innovation reported by the team centers on a dual-level structural enhancement: a stable core that maintains conductivity, and an outer shell designed to buffer volume changes and promote uniform sodium ion distribution.
This core-shell strategy, implemented using a combination of nitrogen-doped carbon and iron-based nanoparticles, led to a substantial increase in both capacity and cycling stability. In laboratory tests, the modified anodes delivered higher reversible capacity and retained performance over hundreds of charge-discharge cycles. Such improvements demonstrate the feasibility of sodium-ion batteries for larger-scale applications, such as grid energy storage and electric vehicles, where cost and resource availability are driving concerns.
In contrast to lithium, which is relatively scarce and concentrated in specific geographic regions, sodium is abundant and widely distributed. However, its larger atomic radius and unique electrochemical properties have historically hindered its competitiveness. The research team’s efforts to overcome these molecular-scale obstacles mark a significant stride in advancing the commercial prospects of sodium-based energy storage.
The reported advance comes amid global efforts to diversify battery chemistries and mitigate dependence on critical materials like lithium and cobalt. While further testing and development are required before commercialization, the study’s positive results signal growing momentum behind sodium-ion technologies.
The findings contribute to a growing body of work aimed at improving the performance of alternative battery systems. As noted in the Tech Xplore article, the researchers are optimistic that the core-shell architecture may be adaptable to other electrochemical systems as well, broadening its potential impact beyond sodium-ion configurations.
