Disclosed herein is a stabilised Na-ion oxide P3 phase of formula (I): P3-Na.sub.xM.sub.yO.sub.z Where, x>0.66, 0.8≤y≤1.0, z≤2; and M is selected from one or more of the group consisting of a 3d transition metal, a 4d transition metal, Al, Mg, B, Si, Sn, Sr and Ca. The stabilised Na-ion oxide P3 phase of formula (I) may be particularly useful as an active material in a Na-ion battery.

A battery comprising an acidified metal oxide (“AMO”) material, preferably in monodisperse nanoparticulate form 20 nm or less in size, having a pH <7 when suspended in a 5 wt % aqueous solution and a Hammett function H.sub.0 >−12, at least on its surface.

The sodium ferrite particle powder according to the present invention is characterized in that at least one metal or more selected from the metal group consisting of silicon, aluminum, titanium, manganese, cobalt, nickel, magnesium, copper and zinc is contained in an amount of 0.05 to 20% by weight in terms of the oxide, and the molar ratio of Na/Fe is 0.75 to 1.25.

A composite metal oxide material and a preparation method thereof, a positive electrode plate, a secondary battery, a battery module, a battery pack and an electrical device are provided. The composite metal oxide material includes a central core and a coating layer on the surface of the central core, in which the central core material has a chemical formula of Li.sub.5Fe.sub.xM.sub.1-xO.sub.4, 0.6≤x≤1; the coating layer material has a chemical formula of LiMO2, M is one or more metal elements with +3 valence, and the absolute value of the difference between the +3-valence ion radius of Fe and the +3-valence ion radius of M is ≤0.02 nm. The composite metal oxide material of the present disclosure makes the secondary battery have high charge capacity, high discharge capacity and long cycle life.

An LiFePO.sub.4 precursor for manufacturing an electrode material of an Li-ion battery and a method for manufacturing the same are disclosed. The LiFePO.sub.4 precursor of the present disclosure can be represented by the following formula (I):
LiFe.sub.(1-a)M.sub.aPO.sub.4  (I)
wherein M and a are defined in the specification, the LiFePO.sub.4 precursor does not have an olivine structure, and the LiFePO.sub.4 precursor is powders constituted by plural flakes.

The present disclosure relates to the technical field of positive electrode lithium-supplementing additives of the lithium battery, and discloses a carbon-coated lithium-rich oxide composite material and a preparation method thereof. The method comprises the following steps: (1) mixing an iron source or a cobalt source with a lithium source, and sintering to obtain a lithium-rich oxide Li.sub.5FeO.sub.4 or Li.sub.6CoO.sub.4; wherein, a molar ratio of the lithium source to the iron source is 5-25:1, and a molar ratio of the lithium source to the cobalt source is 6-30:1; (2) crushing the lithium-rich oxide obtained in the step (1); and (3) mixing the lithium-rich oxide crushed in the step (2) with a carbon source, and sintering to obtain the carbon-coated lithium-rich oxide composite material. The carbon-coated lithium-rich oxide composite material prepared by the method of the present disclosure overcomes the insufficient conductivity of lithium-rich materials, and has good electrochemical properties, which is capable of effectively compensating for active lithium lost during the initial charge-discharge process of the lithium battery.

A lithium iron complex oxide is represented by Li.sub.5FeO.sub.4, two peaks with different quadrupole splitting values (QS) analyzed using .sup.57Fe Mössbauer spectroscopy are shown, one of the two peaks, a peak A, satisfies QS>0, and the other one of the two peaks, a peak B, satisfies QS=0.

A battery comprising an acidified metal oxide (“AMO”) material, preferably in monodispersed nanoparticulate form 20 nm or less in size, having a pH<7 when suspended in a 5 wt % aqueous solution and a Hammett function H.sub.0>−12, at least on its surface.

A method for synthesising metal oxide nanoparticles. The method comprises mixing, to provide a reaction mixture, a precursor solution comprising metal ions with an initiator solution to initiate a nanoparticle precipitation process, and then quenching the precipitation process by adding a quenching agent to the reaction mixture so as to yield a dispersion comprising metal oxide nanoparticles. The resulting metal oxide nanoparticles may have an average diameter of less than 7 nm, for example 5 nm or less.

A battery comprising an acidified metal oxide (“AMO”) material, preferably in monodisperse nanoparticulate form 20 nm or less in size, having a pH<7 when suspended in a 5 wt % aqueous solution and a Hammett function H.sub.0>−12, at least on its surface.