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LiCoO 2 has excellent volume energy density, and is the dominant cathode materials for 3 C electronic products. However, the capacity of LiCoO 2 is not fully utilized, and its cycle stability is not high enough. To preserve the structural stability of LiCoO 2 at high voltage, the mixed ion-electron conductor Li 0.33 La 0.557 Ti 0.8 Cr 0.2 O 3 is coated on LiCoO 2 particles, and the effects of coating amount and annealing temperature on the electrochemical performances are systematically investigated. The capacity retention of the pristine LiCoO 2 in the range of 2.8–4.5 V is only 51.0% after 200 cycles, which is related to the resistance increase of interface and cracks of cathode particles. The coating layer can improve the interface stability and keep the particles intact, and therefore, the capacity retention of the coated sample is significantly increased to 88.2%. • Mixed electron-ion conductor Li 0.33 La 0.557 Ti 0.8 Cr 0.2 O 3 is chosen as coating layer of LiCoO 2. • The coating material is coated on LiCO 2 particles by coprecipitation method. • The hard shell can maintain the particle integrity of LiCoO 2. • The coated particles have excellent cycle stability and rate performance. [ABSTRACT FROM AUTHOR]

Using density functional theory with GGA + U method, the mechanical, thermodynamic properties and minimum thermal conductivity of Gd 2 Zr 2 O 7 pyrochlore are investigated. The obtained lattice parameters and density with GGA + U method are consistent with other experimental and theoretical results. The calculated elastic constants reveal that Gd 2 Zr 2 O 7 pyrochlore is mechanically stable and ductile material under high pressure. From the direction dependence Young's modulus and Zener ratio analysis, it is shown that Gd 2 Zr 2 O 7 pyrochlore is weak anisotropy at 0 GPa and 10 GPa. In addition, the pressure effect on the Young's modulus, bulk modulus, sound wave velocity, shear modulus and minimum thermal conductivity of Gd 2 Zr 2 O 7 pyrochlore are analyzed. Subsequently, the thermodynamic properties such as the constant volume heat capacity, thermal expansion coefficient, Debye temperature, thermal expansion coefficient and entropy under high pressure and temperature are also estimated with the quasi-harmonic Debye model. • Gd 2 Zr 2 O 7 pyrochlore is mechanically stable and ductile under high pressures. • Gd 2 Zr 2 O 7 pyrochlore is weak anisotropy at 0 GPa and 10 GPa. • The thermodynamic properties of Gd 2 Zr 2 O 7 pyrochlore have been investigated. [ABSTRACT FROM AUTHOR]