Breaking Limits of Li-Ion Batteries with High-Voltage Spinel LiNi_0.5Mn_1.5O₄ Nanofiber/Carbon Nanotube Composite Cathodes

Spinel-structured LiNi_0.5Mn_1.5O₄ (LNMO), which is used as a cathode material for lithium-ion batteries, offers economic and eco-friendly advantages, as it operates at a high voltage of 5 V and does not require expensive cobalt. However, challenges such as low electronic conductivity and volume changes due to phase transitions during charging and discharging at 3 V or lower persist, resulting in capacity degradation. In this study, LNMO nanofibers were created using the electrospinning method to tackle the volume expansion issue and maintain structural integrity of the material. In addition, the electrode was constructed with carbon nanotubes as a conductive material to improve electronic conductivity. Electrochemical evaluations showed that LNMO nanofibers combined with carbon nanotubes exhibited a higher capacity and outstanding cyclability compared to LNMO powder.