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 method for pre-lithiating a silicon oxide negative electrode for a secondary battery, specifically a method for pre-lithiation by immersing the silicon oxide negative electrode in an electrolytic solution for wetting, and by applying pressure while a lithium metal is in direct contact with the wetted silicon oxide negative electrode. The silicon oxide negative electrode for a secondary battery manufactured through pre-lithiation provided in the present disclosure has improved initial irreversibility, and a secondary battery manufactured using such a silicon oxide negative electrode for a secondary battery has excellent charge/discharge efficiency.

Methods for producing nanostructures from copper-based catalysts on porous substrates, particularly silicon nanowires on carbon-based substrates for use as battery active materials, are provided. Related compositions are also described. In addition, novel methods for production of copper-based catalyst particles are provided. Methods for producing nanostructures from catalyst particles that comprise a gold shell and a core that does not include gold are also provided.

A method of manufacturing a negative electrode includes providing a negative electrode roll on which a negative electrode structure including a negative electrode current collector, a first negative electrode active material layer formed on one side of the negative electrode current collector, and a second negative electrode active material layer formed on the other side of the negative electrode current collector is wound, preparing a pre-lithiation bath including an impregnation section and a pre-lithiation section and containing a pre-lithiation solution, unwinding the negative electrode structure, moving the negative electrode structure to the impregnation section, and impregnating the negative electrode structure with the pre-lithiation solution; and pre-lithiating the negative electrode structure by moving the same from the impregnation section to the pre-lithiation section. The pre-lithiation is carried out by alternately electrochemically charging the first negative electrode active material layer and the second negative electrode active material layer in the pre-lithiation section.

Process for the preparation of electrodes from a porous material making it possible to obtain electrodes that are useful in electrochemical systems and that have at least one of the following properties: a high capacity in mAh/gram, a high capacity in mAh/liter, a good capacity for cycling, a low rate of self-discharge, and a good environmental tolerance.

A main object of the present disclosure is to provide an active material wherein a volume variation due to charge/discharge is small. The present disclosure achieves the object by providing an active material comprising a silicon clathrate II type crystal phase, and having a composition represented by Na.sub.xSi.sub.136, wherein 1.98<x<2.54.

A method of pre-lithiating a negative electrode for a secondary battery, including: dispersing a lithium metal powder, an inorganic material powder and a binder in a solvent to prepare a mixed solution; and applying the mixed solution to the negative electrode to form a lithium metal-inorganic composite layer on the negative electrode, thereby forming the pre-lithiated negative electrode. Also, a method for pre-lithiating a negative electrode having a high capacity by a simple process. Further, a negative electrode for a secondary battery manufactured through the pre-lithiation method provided in the present invention has an improved initial irreversibility, and secondary batteries manufactured using such a negative electrode for a secondary battery have excellent charge/discharge efficiency.

Articles and methods involving protected electrode structures are generally provided. In some embodiments, a protected electrode structure includes an electrode comprising an alkali metal and a protective structure directly adjacent the electrode. In some embodiments, the protective structure comprises elemental carbon and intercalated ions. In some embodiments, the protective structure is a composite protective structure. The composite structure may comprise an alloy comprising an alkali metal, an oxide of an alkali metal, and/or a fluoride salt of an alkali metal.

Embodiments described herein relate generally to electrochemical cells having pre-lithiated semi-solid electrodes, and particularly to semi-solid electrodes that are pre-lithiated during the mixing of the semi-solid electrode slurry such that a solid-electrolyte interface (SEI) layer is formed in the semi-solid electrode before the electrochemical cell formation. In some embodiments, a semi-solid electrode includes about 20% to about 90% by volume of an active material, about 0% to about 25% by volume of a conductive material, about 10% to about 70% by volume of a liquid electrolyte, and lithium (as lithium metal, a lithium-containing material, and/or a lithium metal equivalent) in an amount sufficient to substantially pre-lithiate the active material. The lithium metal is configured to form a solid-electrolyte interface (SEI) layer on a surface of the active material before an initial charging cycle of an electrochemical cell that includes the semi-solid electrode.

Methods for producing nanostructures from copper-based catalysts on porous substrates, particularly silicon nanowires on carbon-based substrates for use as battery active materials, are provided. Related compositions are also described. In addition, novel methods for production of copper-based catalyst particles are provided. Methods for producing nanostructures from catalyst particles that comprise a gold shell and a core that does not include gold are also provided.