Boosting Initial Coulombic Efficiency in Li-Rich Mn-based Cathodes by Tuning Orbital Hybridization

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Li-rich manganese-based oxides (LRMO) offer high capacity and low cost for lithium-ion batteries.
• Commercialization is hindered by low initial coulombic efficiency (ICE) and oxygen release.
• Understanding transition metal-oxygen orbital hybridization is key to improving LRMO performance.

Purpose of the Study:

• To investigate the effect of glyoxal treatment on LRMO cathode materials.
• To modulate the hybridization between transition metal (TM) 3d and oxygen (O) 2p orbitals.
• To enhance the initial coulombic efficiency (ICE) and electrochemical performance of LRMO.

Main Methods:

• Glyoxal treatment applied to Li-rich manganese-based oxides (LRMO).
• Analysis of transition metal (TM) 3d and oxygen (O) 2p orbital hybridization.
• Electrochemical testing to evaluate initial coulombic efficiency (ICE), specific capacity, and capacity retention.

Main Results:

• Glyoxal treatment reduced Co/Mn t_2g-O 2p hybridization and activated Co²⁺/Co³⁺ redox.
• The ICE of LRMO was significantly improved from 85.3% to 102.5%.
• Achieved a high specific capacity of 291.2 mAh g^-1 at 0.1 C with enhanced capacity retention.

Conclusions:

• Tuning TM 3d-O 2p orbital hybridization is a viable strategy for improving LRMO performance.
• Glyoxal treatment effectively enhances the ICE and specific capacity of LRMO cathodes.
• The findings support the potential of treated LRMO for advanced lithium-ion battery applications.