Provided by the present disclosure are a carbonate precursor that has a high-nickel and low-cobalt sandwich structure, a preparation method therefor and an application thereof. The precursor comprises an inner core and an outer shell layer, wherein the outer shell layer covers at least a part of the outer surface of the inner core. The carbonate precursor having the sandwich structure has the advantages of narrow particle size distribution, good fluidity, and an excellent electrochemical performance, and may be stably produced in both an ammonia-free system and an ammonia-containing system.

Various implementations of a method of forming an electrochemical cell include providing a first electrode, a second electrode, a separator between the first and second electrodes, and an electrolyte in a cell container. The first electrode can include silicon-dominant electrochemically active material. The silicon-dominant electrochemically active material can include greater than 50% silicon by weight. The method can also include exposing at least a part of the electrochemical cell to CO.sub.2, and forming a solid electrolyte interphase (SEI) layer on the first electrode using the CO.sub.2.

The present invention provides a lithium secondary battery that has high energy density and capacity and has excellent cycle characteristics. The present invention relates to a lithium secondary battery including a positive electrode current collector, a negative electrode that is free of a negative electrode active material, a separator that is disposed between the positive electrode current collector and the negative electrode, a positive electrode that is disposed between the positive electrode current collector and the separator and contains a positive electrode active material, and electrolytic solution, wherein the lithium secondary battery includes a layer containing an anion-absorbing conductive polymer between the positive electrode current collector and the separator.

A positive electrode according to the present invention is a positive electrode of a lithium ion secondary battery in which a coating film containing a positive electrode active material is pressed against a surface of a positive electrode base material, and the positive electrode active material is a mixture of a first active material containing single particles of lithium composite oxide and a second active material containing secondary particles which are aggregated single particles of lithium composite oxide.

A battery including a negative electrode active material layer, a positive electrode active material layer and a separator. In a first direction, the positive electrode active material layer includes a first portion and a second portion connected to the first portion. The second portion includes a first end, and the first portion includes a first surface. The first surface is connected to the second portion through a first connection, the first end is away from the first connection and is an end of the positive electrode active material layer, and a thickness of the second portion in a second direction perpendicular to the first direction decreases from the first connection to the first end in the first direction.

A non-aqueous electrolyte secondary battery according to an aspect of the present disclosure is provided with a negative electrode having: a negative electrode collector: a first negative electrode mixture layer provided on the surface of the negative electrode collector; and a second negative electrode mixture layer provided on the surface of the first negative electrode mixture layer. Each of the first negative electrode mixture layer and the second negative electrode mixture layer contains graphite particles. The ratio (S2/S1) of the inter-particle porosity (S2) of the graphite particles in the second negative electrode mixture layer to the inter-particle porosity (S1) of the graphite particles in the first negative electrode mixture layer is 1.1-2.0. The ratio (D2/D1) of the filling density (D2) of the second negative electrode mixture layer to the filling density (D1) of the first negative electrode mixture layer is 0.9-1.1.

A nonaqueous electrolyte secondary battery that is an aspect of the present disclosure comprises a positive electrode, a negative electrode, and a nonaqueous electrolyte solution. The negative electrode comprises a negative electrode current collector and a negative electrode active material layer disposed on the negative electrode current collector. The negative electrode active material layer contains graphite particles A and graphite particles B as negative electrode active materials. The graphite particles A have an internal void ratio of 5% or less. The graphite particles B have an internal void ratio of 8-20%. When the negative electrode active material layer is divided in half in the thickness direction, the region of the half to the side of the outer surface contains more graphite particles A than the region of the half to the side of the negative electrode current collector.

The non-aqueous electrolyte secondary cell according to an embodiment of the present disclosure has a positive electrode, a negative electrode, and a non-aqueous electrolytic solution. The negative electrode has a negative electrode collector and a negative electrode active material layer provided on the negative electrode collector. The negative electrode active material layer contains graphite particles A and graphite particles B as negative electrode active materials. The graphite particles A have an internal void rate of 5% or below. The graphite particles B have an internal void rate of 8 to 20%. When the negative electrode active material layer is halved in the thickness direction, a region on the half closer to the outer surface contains more graphite particles A than a region on the half closer to the negative electrode collector.

Disclosed is a method of fabricating an anode for a lithium-ion battery, including milling a mixture of nano-silicon, one or more carbonaceous materials and one or more solvents, wherein the mixture is retained as a wet slurry during milling. The mixture is carbonised to produce a silicon thinly coated with carbon (Si@C) material. Further milling occurs of a second mixture of the Si@C material, one or more graphite, one or more second carbonaceous materials and one or more second solvents, wherein the second mixture is retained as a second wet slurry during milling. The second mixture is carbonised to produce a Si@C/graphite/carbon material. The anode is formed from the Si@C/graphite/carbon material.

A negative active material for an all solid-state includes an aggregated material of amorphous carbon having pores therein in which primary particles are aggregated, and metal nanoparticles filling in the pores.