A silicon-based negative electrode material, a preparation method therefor, and an application thereof in a lithium ion battery are provided. A lithium ion battery contains the silicon-based negative electrode material. The negative electrode material contains a silicon-containing material and a phosphorus-containing coating layer at the surface of the silicon-containing material. The phosphorus-containing coating layer contains a polymer that has polycyclic aromatic hydrocarbon structural segments. The negative electrode material exhibits improved initial coulombic efficiency, reversible charging specific capacity, cycle charging capacity retention and conductivity. When used in the lithium ion battery, the negative electrode material may improve the energy density of the battery.

A secondary battery including a positive electrode, a negative electrode and a separator interposed between the negative electrode and the positive electrode. The negative electrode includes: a negative electrode current collector; and a negative electrode active material layer on at least one surface of the negative electrode current collector. The negative electrode active material layer includes a mixed active material comprising a carbonaceous active material and a Si-based active material. The secondary battery is controlled by setting a lower limit of state-of-charge (SOC) during operation of the secondary battery depending on a weight mixing ratio of the Si-based active material to the carbonaceous active material. The capacity ratio of the Si-based active material to the carbonaceous active material.

A negative electrode active material for a secondary battery for achieving high initial efficiency and improved discharge capacity and capacity retention. The negative electrode active material for a secondary battery includes first silicon oxide powder particles doped with at least one of alkali metal or alkaline earth metal, and second silicon oxide powder particles, which are not doped, wherein the second silicon oxide powder particles are amorphous. A negative electrode and a secondary battery including the negative electrode active material are also disclosed.

An apparatus for pre-lithiating a negative electrode includes a pre-lithiation reactor having a pre-lithiation solution accommodated therein, a high-pressure chamber surrounding the pre-lithiation reactor, wherein an internal air pressure of the high-pressure chamber is configured to exceed atmospheric pressure, at least one lithium metal counter electrode disposed in the pre-lithiation solution, the lithium metal counter electrode being disposed to face a negative electrode receivable in the pre-lithiation solution in a state that the lithium metal counter electrode is spaced apart from the negative electrode by a predetermined interval, and a charge and discharge unit being connectable to the negative electrode and the lithium metal counter electrode to provide a circuit.

A negative electrode pre-lithiation method comprising the steps of: manufacturing a negative electrode by forming, on a negative electrode current collector, a negative electrode active material layer comprising a negative electrode active material. Then, manufacturing a pre-lithiation cell, which comprises the negative electrode and a lithium metal counter electrode, and impregnating the pre-lithiation cell with a pre-lithiation solution; and charging the pre-lithiation cell with a constant voltage to form a pre-lithiated negative electrode. The pre-lithiation solution comprises 3 vol % to 30 vol % of an organic carbonate compound substituted with halogen.

A method of manufacturing an all-solid-state battery electrode, an all-solid-state battery electrode manufactured by the method, and an all-solid-state battery including the electrode are disclosed. In the method, a specific type of binder included in the electrode is prepared in a fiber form by applying pressure to the binder under specific conditions, so that the fiber-form binder thus prepared has an average fineness that satisfies a specific range. Therefore, the all-solid-state battery including the electrode has an advantage of having high capacity even in the case of electrode thickening for high loading.

Improved electrolytes for lithium-based cells can include a dual salt combination of lithium hexafluorophosphate and lithium bis(fluorosulfonyl)imide or lithium bis(trifluoro-methanesulfonyl)imide, and a solvent that includes dimethyl carbonate, ethylmethyl carbonate and 5 to 25 volume percent of fluoroethylene carbonate. The improved electrolytes can include additives triethyl phosphate, ethoxy(pentafluoro)cyclotriphosphazene, 1,3-propane sultone, or mixtures thereof, and have small limited amounts of additional cosolvents and/or lithium-free organic additives. The improved electrolytes can be used to prepare lithium-based cells with silicon-based active materials as negative electrodes and nickel rich lithium metal oxides as positive electrodes. The lithium-based cells can achieve high energy, high power, fast charge and long cycle life along with good thermal stability.

The present invention relates to a negative electrode including a current collector and a negative electrode active material layer disposed on the current collector, wherein the negative electrode active material layer includes a negative electrode active material, carbon black, and a binder, wherein the negative electrode active material includes silicon particles, and the binder includes a copolymer containing a unit derived from a poly(vinylalcohol) (PVA) and a unit derived from an ionized and substituted acrylate, the binder being included in the negative electrode active material layer in an amount of 18 wt % to 22 wt %.

A positive electrode active material for a non-aqueous electrolyte secondary battery that includes a lithium transition metal composite oxide having a spinel structure and containing nickel and manganese is provided. The positive electrode active material includes a first surface region having a chemical composition with a molar ratio of nickel to manganese of 0.1 or less on the surface of the lithium transition metal composite oxide.

A rechargeable lithium battery includes an electrode laminate including a positive electrode including a positive current collector and a positive active material layer disposed on the positive current collector; a negative electrode including a negative current collector, a negative active material layer disposed on the negative current collector, and a negative electrode functional layer disposed on the negative active material layer; and a separator, wherein the electrode laminate has a ratio (L/W) of a height (L), which is a length in a protruding direction of an electrode terminal, relative to a width (W), which is perpendicular to the protruding direction of the electrode terminal and parallel to the laminate surface, is about 1.1 to about 2.3, the positive active material layer includes a first positive active material including at least one of a composite oxide of a metal selected from cobalt, manganese, nickel, and a combination thereof and lithium and a second positive active material including a compound represented by Chemical Formula 1, the negative electrode functional layer includes flake-shaped polyethylene particles, and an operation voltage is greater than or equal to about 4.3 V.
Li.sub.aFe.sub.1-x1M.sub.x1PO.sub.4  [Chemical Formula 1] In Chemical Formula 1, 0.90≤a≤1.8, 0≤x1≤0.7, and M is Mn, Co, Ni, or a combination thereof.