Various implementations of a method of forming an electrochemical cell include providing a first electrode, a second electrode, a separator between the first and second electrodes, and an electrolyte in a cell container. The first electrode can include silicon-dominant electrochemically active material. The silicon-dominant electrochemically active material can include greater than 50% silicon by weight. The method can also include exposing at least a part of the electrochemical cell to CO.sub.2, and forming a solid electrolyte interphase (SEI) layer on the first electrode using the CO.sub.2.

Electrodes, production methods and mono-cell batteries are provided, which comprise active material particles embedded in electrically conductive metallic porous structure, dry-etched anode structures and battery structures with thick anodes and cathodes that have spatially uniform resistance. The metallic porous structure provides electric conductivity, a large volume that supports good ionic conductivity, that in turn reduces directional elongation of the particles during operation, and may enable reduction or removal of binders, conductive additives and/or current collectors to yield electrodes with higher structural stability, lower resistance, possibly higher energy density and longer cycling lifetime. Dry etching treatments may be used to reduce oxidized surfaces of the active material particles, thereby simplifying production methods and enhancing porosity and ionic conductivity of the electrodes. Electrodes may be made thick and used to form mono-cell batteries which are simple to produce and yield high performance.

A method for making nanoporous nickel composite material comprises: providing a cathode plate and a copper-containing anode plate, electroplating a copper material layer a surface of the cathode plate; laying a carbon nanotube layer on the copper material layer, and forming an overlapped structure of the copper material layer and the carbon nanotube laye; the cathode plate and the overlapped structure are used as a cathode, and a nickel-containing anode plate is used as an anode, plating a nickel material layer on the overlapped structure to form sandwich structure; repeating steps S1 to S3 to obtain a carbon nanotube-reinforced copper-nickel alloy; rolling and annealing the carbon nanotube-reinforced copper-nickel alloy; and etching the carbon nanotube-reinforced copper-nickel alloy to form the nanoporous nickel composite material.

A lithium ion battery including an electrolyte and a lithium titanate negative electrode is provided. The lithium titanate negative electrode includes structures of a lithium titanate core and a conformal layer surrounding each lithium titanate core. The conformal layer either includes titanium oxide with substantially no lithium or has a concentration of lithium ranging from a lower concentration at a surface portion of the layer to a higher concentration at an interior portion of the layer adjacent to the lithium titanate core. A method of preparing the lithium titanate structures and a method of preparing an electrode for a lithium ion battery, wherein the electrode includes lithium titanate structures, are also provided.

A method for manufacturing an all-solid lithium battery includes: providing a substrate; and forming M rows×N columns of lithium battery cells on the substrate, wherein each of the lithium battery cells includes a positive electrode current collector layer, a positive electrode layer, an electrolyte layer, a negative electrode layer, and a negative electrode current collector layer.

A method for fabricating a stacked battery structure. The method includes preparing a plurality of battery layers separately, wherein each battery layer includes a substrate, a film battery element fabricated on the substrate and an insulator formed over the film battery element. The insulator has a flat top surface and the film battery element includes a current collector. The method also includes stacking the plurality of battery layers, wherein the insulator of a first battery layer of the plurality of battery layers bonds to the substrate of a second battery layer of the plurality of battery layers by the flat top surface. The method further includes forming a conductive path within the plurality of battery layers, wherein the conductive path connects with at least one of the current collectors of the plurality of battery layers.

Various implementations of a method of forming an electrochemical cell include providing a first electrode, a second electrode, a separator between the first and second electrodes, and an electrolyte in a cell container. The first electrode can include silicon-dominant electrochemically active material. The silicon-dominant electrochemically active material can include greater than 50% silicon by weight. The method can also include exposing at least a part of the electrochemical cell to CO.sub.2, and forming a solid electrolyte interphase (SEI) layer on the first electrode using the CO.sub.2.

Disclosed is a Proton Exchange Membrane Fuel Cell (PEMFC) incorporating a porous membrane element formed of a porous silicon wafer, in which the pores are coated at least in part with a noble metal. Alternatively, the porous silicon wafer may be sandwiched between paper, carbon or graphite sheet impregnated with a noble metal. The separator is formed of using MEMS Technology. Also disclosed is a lithium ion battery, has a cathode electrode; an anode electrode formed of a porous silicon substrate in which surfaces of the pores of the porous silicon substrate are coated at least in part with a metal silicide; a separator element disposed between the cathode and the anode; and an electrolyte.

Provided herein is a composite anode active material including: a porous carbon structure; a first coating layer on the porous carbon structure and including a non-carbonaceous material capable of intercalating and deintercalating lithium; and a second coating layer on the first coating layer and including a carbonaceous material.

Provided are processes to form microporous silicon useful as an active material in an electrode of an electrochemical cell the processes including subjecting a mixture of silicon oxide and a metal reducing agent, optionally aluminum, to mechanical milling to form mechanically activated silicon oxide/aluminum, thermally treating the silicon oxide/aluminum to reduce the silicon oxide and form Si/Al.sub.2O.sub.3, and removing at least a portion of the alumina from the Si to form a microporous silicon. The resulting electrochemically active microporous silicon is also provided with residual alumina present at 15% by weight or less that demonstrates excellent cycle life and safety.