Improving Fast Charging-Discharging Performances of Ni-Rich LiNi0.8Co0.1Mn0.1O2 Cathode Material by Electronic Conductor LaNiO3 Crystallites

Fast charging-discharging is one of the important requirements for next-generation high-energy Li-ion batteries, nevertheless, electrons transport in the active oxide materials is limited. Thus, carbon coating of active materials is a common method to supply the routes for electron transport, but it is difficult to synthesize the oxide-carbon composite for LiNiO2-based materials which need to be calcined in an oxygen-rich atmosphere. In this work, LiNi0.8Co0.1Mn0.1O2 (NCM811) coated with electronic conductor LaNiO3 (LNO) crystallites is demonstrated for the first time as fast charging-discharging and high energy cathodes for Li-ion batteries. The LaNiO3 succeeds in providing an exceptional fast charging-discharging behavior and initial coulombic efficiency in comparison with pristine NCM811. Consequently, the NCM811@3LNO electrode presents a higher capacity at 0.1 C (approximately 246 mAh g−1) and a significantly improved high rate performance (a discharge specific capacity of 130.62 mAh g−1 at 10 C), twice that of pristine NCM811. Additionally, cycling stability is also improved for the composite material. This work provides a new possibility of active oxide cathodes for high energy/power Li-ion batteries by electronic conductor LaNiO3 coating.

Electrochemical Evaluation of Layered Perovskite YBa0.5Sr0.5Co1.5Fe0.5O5+δ Cathode as a Triple Ionic and Electronic Conductor for Protonic Ceramic Fuel Cells

Protonic ceramic fuel cells (PCFCs) have receiving huge attention as a promising energy conversion device because of their high conversion efficiency, lack of fuel dilution, and high ionic conductivity at intermediate temperature regime (400 ∼ 600 oC). Although this fuel cell system can effectively solve the main obstacle for the commercialization of conventional solid oxide fuel cells, electrochemical performance is currently limited by the cathodic polarization due to insufficient catalytic activity. To overcome this issue, layered perovskite materials, PrBa0.5Sr0.5Co1.5Fe0.5O5+δ, have been discovered as triple ionic and electronic conductor, which enables to simultaneously conduct H+/O2-/e-. Despite great advantages, there is large gap in the thermal expansion coefficient (TEC) between the cathode and electrolyte. Herein, we developed a new triple conducting cathode material, YBa0.5Sr0.5Co1.5Fe0.5O5+δ (YBSCF) to minimize TEC while maintaining the high electro-catalytic activity with excellent hydration properties. Structural analysis, hydration properties, and electrochemical performances of YBSCF cathode were investigated. In particular, the peak power density of YBSCF cathode based on BaZr0.4Ce0.4Y0.1Yb0.1O3-δ (BZCYYb4411) electrolyte attained 0.702 W cm-2 at 600 oC. Moreover, power output is fairly stable for 300 h without observable degradation by applying a constant voltage of 0.7 V at 600 oC.

Li+-Zn2+ tailored nanostructured metallohydrogel based mixed ionic-electronic conductor

A conductive metallohydrogel (MHG) has been obtained via insitu LiOH deprotonation of Mandelic acid derived ligand H2IML followed by coordination of Zn2+ with an objective to fabricate a mixed ionic-electronic...

Theory of the Electrostatic Surface Potential and Intrinsic Dipole Moments at the Mixed Ionic Electronic Conductor (MIEC)-gas Interface

The local activation overpotential describes the electrostatic potential shift away from equilibrium at an electrode/electrolyte interface. This electrostatic potential is not entirely satisfactory for describing the reaction kinetics of a...