Recently, there has been a growing interest in developing sodium ion batteries using sodium instead of lithium, which is becoming more and more scarce, and implementing high capacity energy storage systems.
In this work, we estimated the formation enthalpy and electrode potential of sodium-ion battery cathode material, NaFeCl4 (NFC), using the first-principles calculation.
We performed structural optimizations for the supercells of the intermediate phases Na1+xFeCl4, formed by inserting additional Na atoms into the NFC supercell with 8 fu (48 atoms), to simulate the discharge process in sodium-ion batteries(SIBs).
Then, we calculated the formation enthalpies of the intermediate phases with respect to the intermediate phases according to the inserted Na content, and using these results, estimated the electrode potential.
In this work, all the calculations were carried out by applying the pseudopotential plane-wave method, as implemented in the Quantum ESPRESSO (QE, version 7.2) package. The kinetic cutoff energies were set to 50 Ry for the wave function and the k-point meshes for the Brillouin zone (BZ) integration were set to (2× 2 × 2). A relatively wide plateau region of electrode potential was observed at 3.44 V, from these results, it can be concluded that the NFC compound can be used as a cathode material in all-solid-state sodium-ion batteries(ASSIBs).
This result was published in "Royal Society of Chemistry"under the title of "First-principles study of the electrochemical properties of NaFeCl4 for cathode applications in sodium-ion batteries"(https://doi.org/10.1039/d5ra06124e).
