An electrode for batteries that does not include a metal-film-type current collector is disclosed herein. In some embodiments, the electrode comprises a composite having a core-shell structure including a core having an electrode active material, and a metal material coated on or doped in the surface of the core. A secondary battery having the electrode has increased capacity and energy density and exhibits improved lifespan characteristics.

Silicon particles with a reduced and/or delayed propensity to generate hydrogen gas by reaction with water in aqueous inks for preparing lithium ion battery anodes are prepared by milling silicon, preferably in an oxidative atmosphere, followed by heat treating at an elevated temperature in vacuum or an inert atmosphere.

A submicron sized Si based powder having an average primary particle size between 20 nm and 200 nm, wherein the powder has a surface layer comprising SiO.sub.x, with 0<x<2, the surface layer having an average thickness between 0.5 nm and 10 nm, and wherein the powder has a total oxygen content equal or less than 3% by weight at room temperature. The method for making the powder comprises a step where a Si precursor is vaporized in a gas stream at high temperature, after which the gas stream is quenched to obtain Si particles, and the Si particles are quenched at low temperature in an oxygen containing gas.

A submicron sized Si based powder having an average primary particle size between 20 nm and 200 nm, wherein the powder has a surface layer comprising SiO.sub.x, with 0<x<2, the surface layer having an average thickness between 0.5 nm and 10 nm, and wherein the powder has a total oxygen content equal or less than 3% by weight at room temperature. The method for making the powder comprises a step where a Si precursor is vaporized in a gas stream at high temperature, after which the gas stream is quenched to obtain Si particles, and the Si particles are quenched at low temperature in an oxygen containing gas.

A method of fabricating and using a zinc negative electrode and systems thereof are described. A zinc electroplated electrode including a layer of zinc metal bonded to a surface of an electrically conductive current collector is fabricated by an electroplating process using a zinc electroplating system. The zinc electroplating system includes: a zinc metal anode, a cathode including the current collector for plating zinc thereon, and an electrolyte bath comprising zinc ions. The electroplating process bonds the zinc metal to the surface of the current collector to create the electroplated zinc electrode. The electroplated zinc electrode is used as a negative electrode in a zinc metal cell. The zinc metal cell may be a primary cell or a secondary cell.

A miniature electrochemical cell having a volume of less than 0.5 cc is described. The cell has a casing of first and second ceramic substrates that are hermetically secured to each other to provide an internal space housing an electrode assembly. First and second conductive pathways extend through the ceramic substrates. The pathways have respective inner surfaces that are conductively connected to the respective anode and cathode current collectors and respective outer surfaces that provide for connection to a load. An electrolyte in the internal space of the housing activates the electrode assembly.

A miniature electrochemical cell having a volume of less than 0.5 cc is described. The cell has a casing of first and second ceramic substrates that are hermetically secured to each other to provide an internal space housing an electrode assembly. First and second conductive pathways extend through the ceramic substrates. The pathways have respective inner surfaces that are conductively connected to the respective anode and cathode current collectors and respective outer surfaces that provide for connection to a load. An electrolyte in the internal space of the housing activates the electrode assembly.

In an embodiment, a Li-ion battery cell comprises an anode electrode with an electrode coating that (1) comprises Si-comprising active material particles, (2) exhibits an areal capacity loading in the range of about 3 mAh/cm.sup.2 to about 12 mAh/cm.sup.2, (3) exhibits a volumetric capacity in the range from about 600 mAh/cc to about 1800 mAh/cc in a charged state of the cell, (4) comprises conductive additive material particles, and (5) comprises a polymer binder that is configured to bind the Si-comprising active material particles and the conductive additive material particles together to stabilize the anode electrode against volume expansion during the one or more charge-discharge cycles of the battery cell while maintaining the electrical connection between the metal current collector and the Si-comprising active material particles.

In an embodiment, a Li-ion battery cell comprises an anode electrode with an electrode coating that (1) comprises Si-comprising active material particles, (2) exhibits an areal capacity loading in the range of about 3 mAh/cm.sup.2 to about 12 mAh/cm.sup.2, (3) exhibits a volumetric capacity in the range from about 600 mAh/cc to about 1800 mAh/cc in a charged state of the cell, (4) comprises conductive additive material particles, and (5) comprises a polymer binder that is configured to bind the Si-comprising active material particles and the conductive additive material particles together to stabilize the anode electrode against volume expansion during the one or more charge-discharge cycles of the battery cell while maintaining the electrical connection between the metal current collector and the Si-comprising active material particles.

A purpose of the present invention is to provide a lithium ion secondary battery having improved battery characteristics. The lithium ion secondary battery according to the present invention comprises a negative electrode comprising a negative electrode active material comprising a silicon material and an electrolyte solution comprising an electrolyte solvent comprising an open chain sulfone compound, a fluorinated cyclic carbonate and an open chain carbonate and a supporting salt comprising LiN(FSO.sub.2).sub.2.