A piezoelectric ceramic containing a perovskite-type compound containing at least Pb, Zr, Ti, Mn, and Nb, in which in an X-ray crystal structure analysis chart of the perovskite-type compound, there is no X-ray diffraction peak branching between a (101) plane of a main peak of a PZT tetra phase in a range of 2θ=30.5° to 31.5° and a (110) plane on which an X-ray diffraction peak is in a range of 2θ=30.8° to 31.8°, and a number of X-ray diffraction peaks based on the (101) plane and the (110) plane is one.

The present disclosure is related to a positive electrode active material for lithium secondary batteries, a method for preparing the positive electrode active material, and a lithium secondary battery including the positive electrode active material. The positive electrode active material for lithium secondary batteries includes an overlithiated layered oxide (OLO), and the overlithiated layered oxide includes primary particles having a size in a range of 300 nm to 10 μm in an amount ranging from 50 to 100% by volume with respect to the total overlithiated layered oxide.

Herein disclosed are compositions for passive NOx adsorption and oxidation that include at least a manganese-based oxide and one or more promoter materials and methods for making and using said compositions. The promotor materials may include a rare earth, transition, or main group metal. The compositions may be used in NOx emission control system and adsorbs NOx compounds at low temperatures and then release NOx at higher temperatures, where the NOx can be oxidized, without the hybridized MnOX composition breaking down. The compositions are capable of maintaining a sufficiently large surface area at high temperatures found in the emissions gas streams of internal combustion engines necessary for the complete elimination of NOx.

A positive electrode active material according to the present disclosure includes a lithium composite oxide. The lithium composite oxide is a multiphase mixture including a first phase having a crystal structure belonging to space group C2/m and a second phase having a crystal structure belonging to space group R-3m and includes at least one selected from the group consisting of F, Cl, N, and S. In an XRD pattern of the lithium composite oxide, the integrated intensity ratio I.sub.(20-23)/I.sub.(18-20) of a second maximum peak present in a diffraction angle 2 range of greater than or equal to 20 and less than or equal to 23 to a first maximum peak present in a diffraction angle 2 range of greater than or equal to 18 and less than or equal to 20 satisfies 0.05I.sub.(20-23)/I.sub.(18-20)0.26.

A positive electrode active material according to the present disclosure includes a lithium composite oxide that is a multiphase mixture including a first phase having a crystal structure belonging to a monoclinic crystal (e.g., space group C2/m), a second phase having a crystal structure belonging to a hexagonal crystal (e.g., space group R-3m), and a third phase having a crystal structure belonging to a cubic crystal (e.g., space group Fm-3m or space group Fd-3m). In addition, a battery according to an aspect of the present disclosure includes a positive electrode containing the positive electrode active material, a negative electrode, and an electrolyte. The positive electrode active material according to the present disclosure improves the capacity of the battery.

A class of compositions in the LiMnOF chemical space for Li-ion cathode materials. The compositions are cobalt-free, high-capacity Li-ion battery cathode materials synthesized with cation-disordered rocksalt (DRX) oxide or oxyfluorides, with the general formula Li.sub.xMn.sub.2-xO.sub.2-yF.sub.y (1.1x1.3333; 0y0.6667). The compositions are characterized by: (i) high capacities (e.g., >240 mAh/g); (ii) high energy densities (e.g., >750 Wh/kg between 1.5-4.8V); (iii) favorable cyclability; and (iv) low cost.

Process for precipitating a carbonate or (oxy)hydroxide comprising nickel from an aqueous solution of a nickel salt wherein such process is carried out in a vessel comprising (A) a vessel body, (B) one or more elements that control the hydraulic flow of the slurry formed during the precipitation and that induce a loop-type circulation flow, and (C) a stirrer whose stirrer element is in the vessel but located separately from the element(s) (B).

Disclosed are a precursor for preparation of a lithium composite transition metal oxide, a method for preparing the same and a lithium composite transition metal oxide obtained from the same. More particularly, the transition metal precursor which has a composition represented by Formula 1 below and is prepared in an aqueous transition metal solution, mixed with a transition metal-containing salt, including an alkaline material, the method for preparing the same and the lithium composite transition metal oxide obtained from the same are disclosed.
Mn.sub.aM.sub.b(OH.sub.1-x).sub.2-yA.sub.y(1) wherein M is at least one selected form the group consisting of Ni, Ti, Co, Al, Cu, Fe, Mg, B, Cr, Zr, Zn and Period II transition metals; A is at least one selected form the group consisting of anions of PO.sub.4, BO.sub.3, CO.sub.3, F and NO.sub.3, and 0.5a1.0; 0b0.5; a+b=1; 0<x<1.0; and 0y0.02.

Provided is a battery including: a positive electrode containing a positive electrode active material; a negative electrode; and an electrolyte solution containing a nonaqueous solvent. The positive electrode active material contains a compound represented by composition formula (1) below and having a crystal structure belonging to space group FM3-M: Li.sub.xMe.sub.yO.sub.F.sub.. (1) Here, Me is one or two or more elements selected from the group consisting of Mn, Co, Ni, Fe, Al, B, Ce, Si, Zr, Nb, Pr, Ti, W, Ge, Mo, Sn, Bi, Cu, Mg, Ca, Ba, Sr, Y, Zn, Ga, Er, La, Sm, Yb, V, and C. x, y, , and satisfy the following conditions: 1.7x2.2, 0.8y1.3, 12.5, and 0.52, respectively. The nonaqueous solvent includes at least one solvent selected from hydrofluoroethers, phosphazenes, phosphates, and perfluoropolyethers.

Li-ion battery materials, such as Li-ion cathodes, are provided that have spinels characterized by a close-packed face-centered-cubic rocksalt-type structure and spinel-like ordered TM (the TM preferably occupying one of the two octahedral sites 16c and 16d) that favor fast Li transport kinetics. Such spinels have a larger deviation from a normal spinel and have a formula. Li.sub.1+xTM.sub.2-yO.sub.4-zF.sub.z where 0.2x1, 0.2y0.6, and 0z0.8; and TM is Mn, Ni, Co, Al, Sc, Ti, Zr, Mg, Nb, or a mixture thereof. The spinels achieve a higher gravimetric energy density than traditional spinels while still retaining high capacity at an extremely fast charging/discharging rate.