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This paper presents elasticity solutions for functionally graded piezoelectric plates under electric fields in cylindrical bending. Based on the generalized Mian and Spencer plate theory, the assumption of the material parameters which can vary along the thickness direction of the plate in an arbitrary fashion is kept; however, the materials are extended from elastic materials to piezoelectric materials. The electric potential function is constructed following the forms of the displacement functions in Mian and Spencer plate theory. The essential idea of Mian and Spencer plate theory (J Mech Phys Solids 46:2283–2295, 1998) is that the three-dimensional elasticity equations for inhomogeneous materials can be obtained by two-dimensional solution for homogeneous materials by straightforward substitutions. Through rigorous derivation, the corresponding elasticity solutions of cylindrical bending of functionally graded piezoelectric plates under electric fields are obtained. In the numerical examples, the accuracy of the present solutions is verified and the responses of plates subjected to electrical potential difference and electrical displacement are investigated, respectively. [ABSTRACT FROM AUTHOR]

Li-rich layered-layered-Spinel structure spherical LiMnNiCoO particles was successfully prepared and coated with a uniform layer by a two-step co-precipitation method and evaluated in lithium cells. The structures and electrochemical properties of pristine LiMnNiCoO and AlF-coated LiMnNiCoO were characterized. When the coating amount was 2 wt%, the cathode showed the best cycling performance and rate capability compared to others. The AlF-coated LiMnNiCoO Li-ion cell cathode had a capacity retention of 90.07 % after 50 cycles at 0.5 C over 2.0-4.8 V, while the pristine LiMnNiCoO exhibited capacity retention of only 80.73 %. Moreover, the rate capability and cyclic performance also improved. Electrochemical impedance spectroscopy testing revealed that the improved electrochemical performance might attribute to the AlF coating layer which can suppress the increase of impedance during the charging and discharging process by preventing direct contact between the highly delithiated active material and electrolyte. [ABSTRACT FROM AUTHOR]