An electrochemical cell is provided, which includes a cathode comprising a three dimensional (3D) porous cathode structure, an anode, an electrolyte separator, comprised of a ceramic material, located between the cathode and the anode, and a cathode current collector, wherein the cathode is located between the cathode current collector and the electrolyte separator. The 3D porous cathode structure includes ionically conducting electrolyte strands extending through the cathode from the cathode current collector to the electrolyte separator, pores extending through the cathode from the cathode current collector to the electrolyte separator, and an electronically conducting network extending on sidewall surfaces of the pores from the cathode current collector to the electrolyte separator.

Disclosed is a positive electrode for a lithium-sulfur battery, including a current collector; and a positive electrode active material layer on the current collector, wherein the positive electrode active material layer includes a positive electrode active material and a binder, and the positive electrode active material layer has surface properties defined by the following S.sub.a (arithmetic mean surface roughness of the positive electrode) and S.sub.z (maximum height roughness of the positive electrode) ((i) 1 μm≤S.sub.a≤5 μm, (ii) 10 μm≤S.sub.z≤60 μm (wherein S.sub.a is the average value of the distance from the middle surface of the surface irregularity structure of the positive electrode to the highest point and the lowest point of each irregularity part, and S.sub.z means the distance from the lowest point to the highest point of the positive electrode)) and a method for manufacturing the same.

An energy storage device can include a cathode, an anode, and a separator between the cathode and the anode, where the anode and/or electrode includes an electrode film having a super-fibrillized binder material and carbon. The electrode film can have a reduced quantity of the binder material while maintaining desired mechanical and/or electrical properties. A process for fabricating the electrode film may include a fibrillization process using reduced speed and/or increased process pressure such that fibrillization of the binder material can be increased. The electrode film may include an electrical conductivity promoting additive to facilitate decreased equivalent series resistance performance. Increasing fibrillization of the binder material may facilitate formation of thinner electrode films, such as dry electrode films.

Disclosed is a method of preparing a negative electrode which includes the steps of: forming a cell by sequentially stacking a preliminary negative electrode, a separator, and a lithium metal, immersing the cell in an electrolyte solution comprising a lithium salt and a solvent; applying a current after the cell is immersed in the electrolyte solution containing the lithium salt and the solvent, separating the preliminary negative electrode from the cell after removing the cell immersed in the electrolyte solution from the electrolyte solution, washing the separated preliminary negative electrode, performing a first drying on the washed preliminary negative electrode at room temperature, and performing a second drying on the first dried preliminary negative electrode at a temperature ranging from 30° C. to 70° C. in a vacuum state.

A negative electrode for a lithium secondary battery including a negative electrode active material layer; a lithiation retardation layer on the negative electrode active material layer; and a lithium layer on the lithiation retardation layer, wherein the lithiation retardation layer can be dissolved in an electrolyte. The lithiation retardation layer may include a polymer having at least one of an acrylate repeating unit and a carbonate repeating unit.

Provided herein is a method of making a conductive network by combining uncoated carbon nanotubes and carbon nanotubes coated with an electroactive substance to create an electrically conductive network; and redistributing at least a portion of the electroactive substance. Also provided herein is an electrically conductive network with an active material coating; first carbon nanotubes coated with the active material coating; and second carbon nanotubes partially coated with the active material coating, wherein at least a portion of the surfaces of the second carbon nanotubes directly contact surfaces of other second carbon nanotubes without the active material coating between these second carbon nanotubes, and wherein the first carbon nanotubes and the second carbon nanotubes are entangled to form an electrically conductive network.

Disclosed is a method of manufacturing a negative electrode, wherein a negative electrode structure is electrochemically charged while being pressed with a plurality of pre-lithiation rolls in performing pre-lithiation of the negative electrode structure by a roll-to-roll method, and here, the pressing pressures of the plurality of pre-lithiation rolls are increased in a movement direction of the negative electrode structure. Since the pressing pressures are increased in the movement direction of the negative electrode structure, volume expansion, structural deformation, and damage to an active material due to the pre-lithiation may be prevented, and at the same time, the pre-lithiation may be performed uniformly, and thus it is preferable for improving lifespan characteristics of a negative electrode.

A method for manufacturing an electrochemical device, implementing a process for manufacturing a porous electrode having a porous layer deposited on a substrate, the porous layer having a porosity of between 20% and 60% by volume and pores with an average diameter of less than 50 nm. The method includes providing a substrate and a colloidal suspension including aggregates or agglomerates of monodisperse primary nanoparticles of an active electrode material, having an average primary diameter of between 2 and 60 nm, the aggregates or agglomerates having an average diameter of between 50 nm and 300 nm, then depositing a layer from the colloidal suspension on the substrate, then drying and consolidating the layer to obtain a mesoporous layer, and then depositing a coating of an electronically conductive material on and inside the pores of the layer.

A method for producing a positive electrode active material includes preparing a lithium transition metal oxide in the form of a secondary particle in which primary particles are aggregated, mixing the lithium transition metal oxide and a carbon-based material of a hollow structure having a plurality of pores to form a mixture, and surface treating the mixture in a mechanical manner to form a carbon coating layer on the surface of the lithium transition metal oxide, wherein the carbon-based material of a hollow structure having a plurality of pores has a specific surface area of 200 m2/g or greater and a graphitization degree(ID/IG) of 0.5 or greater.

A silicon-based negative electrode material and a method for preparing the same, a battery including the silicon-based negative electrode material, and a terminal are provided. The silicon-based negative electrode material includes a silicon-based matrix with a low silicon-oxygen ratio and silicon-based particles with a high silicon-oxygen ratio dispersed in the silicon-based matrix with the low silicon-oxygen ratio. A silicon-oxygen ratio of the silicon-based matrix with the low silicon-oxygen ratio is 1:x, and 1<x≤2. A silicon-oxygen ratio of the silicon-based particles with the high silicon-oxygen ratio is 1:y, and 0≤y≤1. The silicon-based matrix with the low silicon-oxygen ratio is silicon dioxide, or the silicon-based matrix with the low silicon-oxygen ratio includes silicon dioxide and silicon-containing crystal particles dispersed in the silicon dioxide.