Oxygen vacancy chemistry in oxide cathodes.

Secondary batteries are a core technology for clean energy storage and conversion systems, to reduce environmental pollution and alleviate the energy crisis. Oxide cathodes play a vital role in revolutionizing battery technology due to their high capacity and voltage for oxide-based batteries. However, oxygen vacancies (OVs) are an essential type of defect that exist predominantly in both the bulk and surface regions of transition metal (TM) oxide batteries, and have a crucial impact on battery performance.

Origin of the Seriously Limited Anionic Redox Reaction of Li-Rich Cathodes in Sulfide All-Solid-State Batteries.

Li-rich layered oxide (LLO) cathode materials with mixed cationic and anionic redox reactions display much higher specific capacity than other traditional layered oxide materials. However, the practical specific capacity of LLO during the first cycle in sulfide all-solid-state lithium-ion batteries (ASSLBs) is extremely low. Herein, the capacity contribution of each redox reaction in LLO during the first charging process is qualitatively and quantitatively analyzed by comprehensive electrochemical and structural measurements.

Direct Observation of Li-Ion Transport Heterogeneity Induced by Nanoscale Phase Separation in Li-rich Cathodes of Solid-State Batteries.

Li-rich layered oxide (LLO) cathode materials with high specific capacities could significantly enhance the energy density of all-solid-state lithium batteries (ASSLBs). However, the specific practical capacities of LLO materials in ASSLBs are extremely low due to poor initial activation. Here, scanning transmission electron microscopy with in situ differential phase contrast imaging was first used to study the initial activation mechanism of Li Ni Co Mn O .