Intelligent phase-transition MnO₂ single-crystal shell enabling a high-capacity Li-rich layered cathode in Li-ion...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Layered, Li-rich Mn-based oxides (LLMOs) offer high energy density for next-generation batteries.
• Their practical use is hindered by low initial coulombic efficiencies and poor cycling stability.

Purpose of the Study:

• To enhance the electrochemical performance of LLMO cathodes.
• To address limitations in coulombic efficiency and cycling stability.

Main Methods:

• Hydrothermal synthesis using KMnO4 and MnSO4 to create a nano-single crystal composite (SCMO) shell on LLMO materials (SCMO@LLMO).
• Characterization of the SCMO@LLMO structure and electrochemical properties.

Main Results:

• The SCMO shell improves the electrochemical reaction and surface stability of LLMO cathodes.
• The optimal SCMO@LLMO-2.0 sample showed high initial discharge capacity (238.2 mA h g⁻¹ at 1C) and improved cycling performance (84.67% retention at 1C after 200 cycles).
• Enhanced initial coulombic efficiency (89.6% at 1C) was observed.

Conclusions:

• The hydrothermal synthesis of SCMO@LLMO is an effective strategy to boost LLMO cathode performance.
• This approach provides a foundation for developing high-performance LLMO primary battery cathodes.