Engineering Homogeneous Dopant Distribution via Nano-Sol Infusion: A Strategy for Microcrack Suppression in LiNiO₂.

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• Lithium nickel oxide (LiNiO2) is a key material for high-energy-density lithium-ion batteries.
• However, its commercialization is hindered by limited cycle life due to structural degradation during cycling.
• Conventional doping methods often result in poor dopant distribution and particle agglomeration.

Purpose of the Study:

• To develop a novel doping strategy for LiNiO2 to enhance its structural stability and cycle life.
• To overcome the limitations of conventional solid-state doping methods.
• To improve the overall performance of lithium-ion batteries.

Main Methods:

• A nano-sol infusion doping strategy was employed to uniformly introduce nanoscale dopant precursors into the cathode precursor.
• This method uses minimal solvent and simple equipment, facilitating homogeneous dopant distribution.
• The synthesized infusion-doped LiNiO2 (ID-LNO) was characterized for structural and electrochemical properties.

Main Results:

• The ID-LNO exhibited superior capacity retention (86.06% after 100 cycles at 1 C) compared to undoped and solid-state doped LNO.
• Enhanced structural stability was observed, including suppressed microcrack formation and mitigated c-axis contraction during phase transitions.
• The nano-sol infusion method ensured homogeneous dopant distribution and stable incorporation.

Conclusions:

• Nano-sol infusion doping is a highly effective strategy for improving the performance and durability of LiNiO2.
• This method fundamentally alleviates structural degradation issues in LiNiO2.
• The approach shows potential for various dopants and layered oxide compositions (NCM, NCA) in developing advanced lithium-ion batteries.