A cross-like hierarchical porous lithium-rich layered oxide with (110)-oriented crystal planes as a high energy density cathode for lithium ion batteries

Abstract

Lithium-rich layered oxide (LLO) is a promising cathode for high energy density batteries due to its combined large specific capacity (>250 mA h g⁻¹) and high discharge voltage; however its application is limited by drawbacks including low rate capability, poor cycling stability and rapid voltage decay. To address these issues, a novel architecture, cross-like hierarchical porous LLO microsized aggregates made of ∼100 nm primary particles with highly exposed (110) crystal planes, has been successfully developed by a morphology-conserved solid-state Li implantation method. Electrochemical performances demonstrate that the as-synthesized LLO exhibits a high initial capacity of 276 mA h g⁻¹ at 0.1C, a remarkable rate capability of 143 mA h g⁻¹ at 20C, a good cycling stability of 132 mA h g⁻¹ after 300 cycles at 20C, and no significant voltage decay after 200 cycles at 0.5C. When it is coupled with a graphite anode, an energy density of 436 W h kg⁻¹ (based on the total active materials of the cathode and anode) and an energy retention of 83% after 100 cycles are achieved. This architecture establishes a great strategy to engineer LLO for its application in high energy density batteries.