A polymorphic lithium-silicon compounds for use in pure silicon anode of lithium-ion battery and use thereof are provided. The pure silicon anode includes nucleuses which have one or more structures of Li.sub.4.1Si_Cmcm, Li.sub.13Si.sub.4_Pbam, Li.sub.2Si_C12m1, and LiSi_I41/AZ. It was generally believed Li.sub.4.1Si_Cmcm to be a high-temperature stable phase, not presenting at room temperature or in the pure silicon anode of lithium-ion battery, but this present invention proves that Li.sub.4.1Si_Cmcm can exist in the disclosed material. After lithiation process, the pure silicon anode can have a structure of one or more of Li.sub.4.1Si_Cmcm, Li.sub.13Si.sub.4_Pbam, Li.sub.2Si_C12m1, and LiSi_I41/AZ, with extremely improved capacity. The present disclosure may increase the electrical capacity of the pure silicon anode in actual use and solve the problem of the existing pure silicon anode that the volume expansion after repeated lithiation and delithiation leads to electrode damage and battery failure.

A main object of the present disclosure is to provide an active material wherein the volume variation of an electrode layer during charge/discharge may be suppressed. The present disclosure achieves the object by providing an active material used for an all solid state battery, the active material comprising at least Si, and in infrared spectrum, when a maximum peak intensity in 900 cm.sup.−1 or more and 950 cm.sup.−1 or less is regarded as I.sub.1, and a maximum peak intensity in 1000 cm.sup.−1 or more and 1100 cm.sup.−1 or less is regarded as I.sub.2, the I.sub.1 and the I.sub.2 satisfy 0.55≤I.sub.2/I.sub.1≤1.0, and 0.01≤I.sub.1.

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.

The electrode manufacturing method for manufacturing an electrode provided with an active material layer that contains an active material doped with alkali metal. In an atmosphere with an oxygen concentration of 1 volume % or more and 18 volume % or less, the active material is doped with alkali metal using a dope solution containing alkali metal ions. In a manufacturing method for a power storage device, a negative electrode active material contained in a negative electrode active material layer of a negative electrode is doped with alkali metal using a dope solution containing alkali metal ions in an atmosphere with an oxygen concentration of 1 volume % or more and 18 volume % or less. After the doping with alkali metal, the negative electrode, a separator, and an electrode different from the negative electrode are sequentially stacked to form the electrode cell.

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.

A solid lithium cell is formed by stacking an etched copper substrate, a layer of graphite, an electrolyte, and a layer of nickel, manganese, and cobalt oxides. The electrolyte is in contact with the graphite layer and the layer of nickel, manganese, and cobalt oxides. The copper substrate forms the anode of the cell. The layer of nickel, manganese and cobalt oxides forms the cathode of the cell. The electrolyte is a solid lithium-based electrolyte. The graphite layer has a first solid electrolyte interface produced during a pre-lithiation with a liquid lithium-based electrolyte and a second solid electrolyte interface produced during a pre-lithiation with the solid lithium-based electrolyte.

A negative electrode active material includes graphite and silicon oxide. On a rectangular coordinate system having an SOC of the battery on a horizontal axis and a dimension of the battery on a vertical axis, a charging profile of the battery includes a first stage and a second stage. When the battery is charged at a current rate equal to or higher than an inherent current rate, a first slope is less steep than a second slope. When the battery is charged at a current rate lower than the inherent current rate, the first slope is steeper than the second slope. During the initial charging, at least charging in the first stage is performed at a current rate lower than the inherent current rate. After the initial charging proceeds to the second stage, the thermal aging is performed at an SOC included in the second stage.

Provided herein are an all-solid-state battery having an intermediate layer including a metal and a metal nitride, and a method for manufacturing the same.

The present invention relates to a negative electrode for the use in alkali-ion rechargeable battery where electrochemically active material is selected from the Group IV semiconductors, the active material forming a heterofibrous monolithic anode body, the anode body comprises at least of 2 layers of aligned and/or stacked and/or interlaced fibers wherein the layers of fibers are spot-fused together at points of their physical contact and further over-lithiated by ex-situ anisotropic chemical and or electrochemical means forming a monolithic wafer-like self-standing over-lithiated alloying type anode where part of the lithium excess is subsequently depleted during forming artificial SEI-layer.

The present invention relates to a cathode, a lithium air battery including a cathode, and a method of preparing the lithium air battery. A cathode configured to use oxygen as a cathode active material, the cathode including: a lithium alloy represented by Formula 1
Li.sub.xM.sub.y  Formula 1 wherein, in Formula 1, M is Pb, Sn, Mo, Hf, U, Nb, Th, Ta, Bi, Mg, Al, Si, Zn, Ag, Cd, In, Sb, Pt, or Au, 0<x≤10, 0<y≤10, and 0<x/y<10.