Method for Activating Electrochemical Properties of Cathode Active Materials for Lithium Secondary Batteries and Cathode Active Materials for Lithium Secondary Batteries

Manufacturing Method for Cathode Materials Activating Oxygen Redox via Lithium Vacancy Formation and Heat Treatment

This technology maximizes the reversibility of oxygen redox reactions during initial charge and discharge cycles by forming lithium vacancies within the crystal structure of lithium-rich metal oxides and performing heat treatment at a specific temperature to induce the diffusion and redistribution of transition metals (M, M').

Lithium-rich cathode materials have historically suffered from irreversible oxygen gas evolution and structural collapse in the 4.4–4.6V range during initial charging, leading to lower actual reversible capacity compared to their high theoretical capacity and poor cycle stability.

By chemically or electrochemically delithiating 10–30 mol% of the total lithium content to create lithium vacancies while maintaining structural integrity, followed by heat treatment at 50–300°C for 6–24 hours to enhance activity, this process can be used to reliably secure the properties required for lithium-ion battery cathode materials.

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Key Features:

• A delithiation step that removes a portion of lithium from layered lithium-rich metal oxides to generate a high density of lithium vacancies.
• A heat treatment step for the delithiated lithium-rich metal oxide to facilitate the diffusion and dispersion of constituent elements.
• Configuration for generating lithium vacancies by chemically or electrochemically delithiating 10 to 30 mole percent of the total lithium content.
• Configuration for activating initial oxygen redox reactions by redistributing transition metals through heat treatment following lithium vacancy formation.

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