New doping helps sodium batteries retain 60% capacity for 300 cycles

Researchers at Tokyo University of Science have demonstrated that doping the cathode material of sodium-ion batteries with scandium significantly improves their cycling stability. Specifically, introducing scandium into the P′2 polytype of sodium manganese oxide (Na2/3[Mn1−xScx]O2) cathodes helps maintain structural integrity by altering crystal growth, reducing side reactions with the electrolyte, and enhancing moisture stability. In practical tests, coin-type full cells with 8% scandium doping retained 60% of their capacity after 300 charge-discharge cycles, addressing the common problem of rapid capacity fading caused by Jahn-Teller distortion in layered sodium manganese oxides. This study not only highlights scandium doping as a promising strategy to extend the lifespan and performance of sodium-ion batteries but also provides a broader approach for improving the structural stability of layered metal oxides used in battery applications. While scandium is an expensive metal, the findings suggest its feasibility for developing high-performance, long-life sodium-ion batteries