Compounds, particles, and cathode active materials that can be used in lithium ion batteries are described herein. Methods of making such compounds, powders, and cathode active materials are described. The particles have a particle size distribution with a D50 ranging from 10 μm to 20 μm.

An electrode active material for lithium-ion secondary batteries that has a sufficiently high initial capacity, improved charge-and-discharge cycle characteristics, and improved coulombic efficiency in the mid-term charge-and-discharge cycles can be obtained by a phosphorus-containing low-crystalline vanadium sulfide comprising vanadium, phosphorus, and sulfur as constituent elements, the composition ratio of the phosphorus to the vanadium (P/V) being 0.1 to 1.0 in terms of the molar ratio, the composition ratio of the sulfur to the vanadium (S/V) being 4.00 to 10.00 in terms of the molar ratio.

The present disclosure discloses a lithium-manganese rich material and a preparation method and a use thereof.

The present disclosure provides a cobalt-free cathode material of a lithium ion battery, a method for preparing the cobalt-free cathode material, and the lithium ion battery. A general formula of the cobalt-free cathode material is Li.sub.xNi.sub.aMn.sub.bR.sub.cO.sub.2, wherein, 1≤x≤1.15, 0.5≤a≤0.95, 0.02≤b≤0.48, 0<c≤0.05, and R is aluminum or tungsten. Therefore, as the cobalt-free cathode material is free of metal cobalt, the cost of the cathode material can be lowered effectively. Aluminum or tungsten in the cobalt-free cathode material can stabilize a crystal structure of the cathode material better, such that the lithium ion battery has excellent rate capability and cycle performance, and furthermore, good cycling stability of the lithium ion battery can be still maintained under a high-temperature and high-pressure testing condition.

The present invention comprises: an overlithiated layered oxide represented by chemical formula 1 below; and an ion-conductive coating layer on the overlithiated layered oxide represented by chemical formula 1: [chemical formula 1] .sub.rLi.sub.2MnO.sub.3.Math.(1-r)Li.sub.aNi.sub.xCo.sub.yMn.sub.zM1.sub.1−(x+y+z)O.sub.2 (in chemical formula 1, 0<r≤0.6, 0<a≤1, 0≤x≤1, 0≤y<1, 0≤z<1, and 0<x+y+z<1, and M1 is at least one selected from among Na, K, Mg, Al, Fe, Cr, Y, Sn, Ti, B, P, Zr, Ru, Nb, W, Ba, Sr, La, Ga, Mg, Gd, Sm, Ca, Ce, Fe, Al, Ta, Mo, Sc, V, Zn, Cu, In, S, B, Ge, Si, and Bi).

The invention provides a positive electrode active material for a lithium ion battery, comprising a lithium transition metal-based oxide powder, the powder comprising single crystal monolithic particles comprising Ni and Co and having a general formula Li.sub.1+a ((Ni.sub.z (Ni.sub.1/2 Mn.sub.1/2).sub.y Co.sub.x).sub.1−kA.sub.k).sub.1-a 02, wherein A is a dopant, −0.02<a≤0.06, 0.10≤x≤0.35, 0≤z≤0.90, x+y+z=1 and k≤0.01, the particles having a cobalt concentration gradient wherein the particle surface has a higher Co content than the particle center.

A solid electrolyte material is represented by the following compositional formula (1):
Li.sub.3-3δ-2aY.sub.1+δ-aM.sub.aCl.sub.6-x-yBr.sub.xI.sub.y where, M is at least one selected from the group consisting of Ta and Nb; and −1<δ<1, 0<a<1.2, 0<(3−3δ−2a), 0<(1+δ−a), 0≤x≤6, 0≤y≤6, and (x+y)≤6 are satisfied.

A positive electrode active material for a lithium ion battery comprises a lithium transition metal-based oxide powder, the powder comprising single crystal monolithic particles comprising Ni and Co and having a general formula Li.sub.1+a (Ni.sub.z Mn.sub.y Co.sub.x Zr.sub.q A.sub.k).sub.1−a O.sub.2, wherein A is a dopant, −0.025≤a<0.005, 0.60≤z≤0.95, y≤0.20, 0.05≤x≤0.20, k≤0.20, 0≤q≤0.10, and x+y+z+k+q=1. The particles have a cobalt concentration gradient wherein the particle surface has a higher Co content than the particle center.

A process for producing a surface-modified particulate lithium nickel metal oxide material is provided. The process comprises the addition of a controlled quantity of a coating liquid to lithium nickel metal oxide particles followed by a calcination step.

A lithium ion conductive solid electrolyte contains a lithium ion conductive powder having a garnet-type crystal structure including at least Li, La, Zr, and O, and a lithium ion conductive polymer. The lithium ion conductive solid electrolyte can maintain its shape without use of an additional polymer different from the lithium ion conductive polymer. The lithium ion conductive solid electrolyte exhibits an activation energy of 30 kJ/mol or less at 20° C. to 80° C.