Depolarization of Li‐rich Mn‐based oxide via electrochemically active Prussian blue interface providing superior rate capability

Abstract

The high‐rate cyclability of Li‐rich Mn‐based oxide (LMO) is highly limited by the electrochemical polarization resulting from the slow kinetic of the Li2MnO3 phase. Herein, the Prussian blue (PB) coating layer with specific redox potential is introduced as a functionalized interface to overcome the side effect and the escaping of O on the surface of LMO, especially its poor rate capability. In detail, the PB layer can restrict the large polarization of LMO by sharing overloaded current at a high rate due to the synchronous redox of PB and LMO. Consequently, an enhanced high rate performance with capacity retention of 87.8% over 300 cycles is obtained, which is superior to 50.5% of the pristine electrode. Such strategies on the high‐rate cyclability of Li‐rich Mn‐based oxide compatible with good low‐rate performances may attract great attention for pursuing durable performances.

Understanding the Synthesis Kinetics of Single‐Crystal Co‐Free Ni‐Rich Cathodes

“…In addition, the long-term charge/discharge curves of high-temperature synthesis display significant voltage decay (Figure S13a Supporting Information), which indicates a serious electrochemical degradation of the structural and chemical instability. [40][41][42][43] In sharp contrast, the voltage distribution of molten-salt synthesis remains small changes (Figure S13b Supporting Information), which confirms the stable physical and chemical structure of molten-salt synthesis. In order to further analyze the reaction kinetics of these two materials, we analyzed the internal resistance of the electrodes after 200 cycles.…”

Effects of Bending on Nucleation and Injection of Oxygen Vacancies into the Bulk Lattice of Li‐Rich Layered Cathodes

“…By developing a procedure to have one phase appropriately distributed in the other phase, bending of the Li 2 MnO 3 phase can be mitigated. [47][48][49][50]…”

Lithium-Ion Conductor Li2ZrO3-Coated Primary Particles To Optimize the Performance of Li-Rich Mn-Based Cathode Materials

“…With the development of electric vehicles and grid energy storage, there are high expectations for LIBs with high energy density. − Currently, it is urgent to develop cathode materials with high specific capacity and high voltage to enhance the energy density of LIBs. In recent years, the lithium-rich manganese-based cathode material (LRMC) has been highly anticipated for its high specific capacity, high operating voltage, low production cost, and environmental friendliness. − This kind of cathode material has attracted widespread attention from scientific research and industry . However, the LRMC still faces all-round challenges including high first irreversible capacity, poor Coulombic efficiency, poor rate capacity, and voltage decay, which have restricted the large-scale use and industrialization of the LRMC. − Therefore, numerous scholars have made a series of important research in enhancing the performance of the LRMC.…”