A method for manufacturing an electrode having a porosity of between 20% and 60% by volume and pores with an average diameter of less than 50 nm. In the method, provision is made of a substrate and a colloidal suspension of aggregates or agglomerates of monodisperse primary nanoparticles of an active electrode material, having an average primary diameter D.sub.50 of between 2 and 100 nm, the aggregates or agglomerates having an average diameter D.sub.50 of between 50 nm and 300 nm. A layer is deposited from said colloidal suspension on the substrate. The deposited layer is then dried and consolidated to obtain a mesoporous layer. A coating of an electronically conductive material is then deposited on and inside the pores of the porous layer. Such a porous electrode can be used in lithium-ion microbatteries.

A positive active material, comprising a lithium transition metal composite oxide containing Co and R elements and an M element. The lithium transition metal composite oxide has a P6.sub.3mc crystal structure. The M element includes at least one of Al, Mg, Ti, Mn, Fe, Ni, Zn, Cu, Nb, Cr, Y, or Zr. The R element includes at least one of F or Cl. A molar content of the R element is n.sub.R, a sum of a molar content of the Co element and a molar content of the M element is n.sub.Co+M, and a ratio δ of n.sub.R to n.sub.Co+M is 0<δ≤0.01. The crystal structure of the positive active material according to this application is highly stable, thereby improving cycle performance and thermal stability of the electrochemical device.

The present invention relates to a negative electrode for a lithium secondary battery and a lithium secondary battery comprising the same. The negative electrode for a lithium secondary battery comprises a current collector and a negative electrode active material layer formed on the current collector, wherein the negative electrode active material layer includes a first negative electrode active material and a first binder, and a second active material layer formed on the first active material layer and including a second negative electrode active material and a second binder, a content of the first binder is greater than that of the second binder, a loading level of the negative electrode active material layer is 10 mg/cm.sup.2 to 30 mg/cm.sup.2, a loading level of the first active material layer is 4 mg/cm.sup.2 to 25 mg/cm.sup.2, a loading level of the second active material layer is 4 mg/cm.sup.2 to 25 mg/cm.sup.2, and a loading level of the second active material layer is equal to or higher than that of the first active material layer.

A method for processing a negative electrode plate, a sodium-metal negative electrode plate and related devices. In a vacuum environment, the metal vapor reacts with oxygen, and the metal oxide formed by the reaction is plated on the surface of the sodium-metal negative electrode plate to form a metal oxide protective layer with high mechanical strength and stable chemical properties. The metal oxide protective layer can greatly reduce the phenomenon of low yield and performance deterioration caused by the reaction of sodium metal with air and water during the processing of the sodium-metal negative electrode plate. Since the metal oxide has a nanoscale thickness, it can form a corresponding sodium salt with sodium metal under electrochemical conditions, thereby improving the sodium ion transport rate on the surface of the sodium-metal negative electrode plate and improving the battery’s kinetic performance.

This positive electrode active material for non-aqueous electrolyte secondary batteries is composed of single particles and/or secondary particles containing not more than 10 primary particles, of a lithium transition metal composite oxide containing not less than 85% by mole of Ni relative to the total number of moles of metal elements other than Li. In the positive electrode active material, the particle cross-sections of the single particles and the primary particles of the lithium transition metal composite oxide each have a polygonal shape that includes a side having a length of 1.5 μm or greater, and at least three interior angles of the polygonal shape are 45-160°.

An electrode plate includes a current collector and an active material layer provided on the current collector. The active material layer includes a first composite particle including a first active material particle and a first binder particle and a second composite particle including a second active material particle and a second binder particle. In a thickness direction of the active material layer, the first composite particle is closer to the current collector than the second composite particle. A quantity of the first active material particle contained in the first composite particle is greater than a quantity of the second active material particle contained in the second composite particle. Components of both the first binder particle and the second binder particle include polypropylene.

An embodiment of the present invention relates to a silicon-based carbon composite, a preparation method therefor, and an anode active material for a lithium secondary battery, comprising same, and, more specifically, the silicon-based carbon composite of the present invention is a silicon-based carbon composite having a core-shell structure, wherein the core comprises silicon, silicon oxide compound and magnesium silicate, the shell comprises at least two carbon layers comprising a first carbon layer and a second carbon layer, and the second carbon layer is reduced graphene oxide, and thus, during application of the silicon-based carbon composite to an anode active material for a secondary battery, the charge/discharge capacity, initial charge/discharge efficiency and capacity retention of the secondary battery can be improved.

Provided is an electrode, including: a collector; and an active material layer formed on the collector, wherein the active material layer contains sulfur-modified polyacrylonitrile and a lithium-titanium oxide, wherein an average secondary particle diameter of the sulfur-modified polyacrylonitrile is larger than an average secondary particle diameter of the lithium-titanium oxide, and wherein a content of the sulfur-modified polyacrylonitrile in the active material layer is from 5 mass % to 85 mass %, and a content of the lithium-titanium oxide in the active material layer is from 5 mass % to 85 mass %.

A positive electrode material includes a first powder. The first powder includes first secondary particles. The first secondary particles includes at least two first primary particles. An average particle diameter D1 of the first primary particles is 500 nm to 3 μm. An average particle diameter D2 of the first secondary particles is 2 μm to 8 μm. A ratio K1 of D2 to D1 satisfies: 2≤K1≤10. The first powder includes an element Co and optionally further includes a metal element M. The metal element M includes at least one of Mn, Al, W, Ti, Zr, Mg, La, Y, Sr, or Ce. A molar ratio R1 between Co and M is greater than or equal to 5. The positive electrode material achieves relatively high rate performance and safety on the basis of achieving a relatively high energy density.

A positive electrode material includes a first lithium manganese iron phosphate material in an aggregate form, a second and third lithium manganese iron phosphate materials in an aggregate and/or single-crystal-like form, and a fourth and fifth lithium manganese iron phosphate materials in a single-crystal-like form. D.sub.50.sup.5<D.sub.50.sup.4<D.sub.50.sup.3<D.sub.50.sup.2<D.sub.50.sup.1, D.sub.50.sup.2=aD.sub.50.sup.1, D.sub.50.sup.3=bD.sub.50.sup.1, D.sub.50.sup.4=cD.sub.50.sup.1, D.sub.50.sup.5=dD.sub.50.sup.1, and 5 μm≤D.sub.50.sup.1≤15 μm. 0.35≤a≤0.5, 0.2≤b≤0.27, 0.17≤c≤0.18, and 0.15≤d≤0.16. Molar ratios of manganese to iron in the first, the second, the third and the fourth lithium manganese iron phosphate materials increase sequentially, and a molar ratio of manganese to iron in the fifth lithium manganese iron phosphate material is greater than that in the third lithium manganese iron phosphate material.