Researchers have developed a high-energy, high-power hybrid sodium-ion battery that could be a viable alternative to lithium-ion batteries.

Led by Jeung Ku Kang, a team from the Korea Advanced Institute of Science and Technology (KAIST) and Lawrence Berkeley National Laboratory has found a way to enhance sodium-ion hybrid energy storage systems through an innovative hybrid energy storage system that integrates anode and cathode materials.

Sodium, a metal 500 times more abundantly available than lithium, shows much promise for electrochemical storage technologies. While iron-based sulfides are environmentally non-toxic, low-cost, and promising anode materials, they have low electrical conductivity, significant volume change during charging/discharging cycles, and slow kinetics.

This necessitated the development of next-generation energy storage materials.

In a recent paper in the Energy Storage Materials journal, the researchers said they combined these materials to allow for high energy density, rapid charging capabilities, and robust long-term stability over many charging cycles, addressing the limitations plaguing sodium-ion technologies.

Sodium-ion hybrid energy storage cells that can use the different potential windows of capacitor-type cathodes and battery-type anodes have attracted a lot of attention because they could, in principle, simultaneously allow for high energy density and fast-rechargeable power density.

The team synthesized iron sulfide-embedded S-doped carbon or graphene (FS/C/G) anode materials from the iron-based metal-organic framework or graphene oxide heterostructures via graphitic carbon formation and sulfidation.

This optimized the balance and minimized the disparities in energy storage rates between the electrodes.

They also achieved high-energy density and fast-rechargeable sodium ion cells by developing a low-crystallinity multivalence iron FS/C/G anode and a ZIF-derived porous carbon cathode.

Through this, the team was able to offer a more abundant and potentially cheaper alternative to lithium-ion systems, which will be especially useful for large-scale energy storage applications.

Earlier this year, Australian and American researchers developed a new type of aqueous sodium-ion battery that they claimed would last for over 13,000 charge cycles.

In February 2024, another team from Liverpool University discovered a solid material that rapidly conducts lithium-ions, which consists of non-toxic, earth-abundant materials.