A rechargeable lithium cell comprising an anode, a separator, a cathode, and an electrolyte or an electrolyte solution, characterized in that said anode comprises (a) a metal capable of being alloyed with lithium and (b) a metal incapable of being alloyed with lithium, said anode contains lithium when charging is operated, and wherein an anode terminal is extended from a portion formed of said metal (b).

Rechargeable lithium battery

The present invention relates to a power storage device including: a positive electrode having a positive-electrode current collector, a positive-electrode active material with a plurality of first projections on the positive-electrode current collector, and a first insulator on an end of each of the plurality of first projections; a negative electrode having a negative-electrode current collector, a negative-electrode active material with a plurality of second projections on a surface of the negative-electrode current collector, and a second insulator on an end of each of the plurality of second projections; a separator between the positive electrode and the negative electrode; and an electrolyte provided in a space between the positive electrode and the negative electrode and containing carrier ions. In each of the first projections and the second projections, a ratio of the height to the width is 3 or more and 1000 or less to 1, i.e. (3 to 1000):1.

Power storage device

High capacity silicon based anode active materials are described for lithium ion batteries. These materials are shown to be effective in combination with high capacity lithium rich cathode active materials. Supplemental lithium is shown to improve the cycling performance and reduce irreversible capacity loss for at least certain silicon based active materials. In particular silicon based active materials can be formed in composites with electrically conductive coatings, such as pyrolytic carbon coatings or metal coatings, and composites can also be formed with other electrically conductive carbon components, such as carbon nanofibers and carbon nanoparticles. Additional alloys with silicon are explored.

High capacity anode materials for lithium ion batteries

Disclosed are a negative active material for a rechargeable lithium battery including a spherically-shaped natural graphite-modified composite particle including: a spherically-shaped natural graphite particle where flake-shaped natural graphite fragments build up and assemble into a cabbage or random shape; and amorphous or semi-crystalline carbon, wherein an open gap between the flake-shaped natural graphite fragments is positioned on a surface part or inside the spherically-shaped natural graphite particle, the amorphous or semi-crystalline carbon is coated on the surface of the spherically-shaped natural graphite particle, and the amorphous or semi-crystalline carbon is present in the open gap, and thereby the open gap positioned on the surface part and inside the spherically-shaped natural graphite particle is maintained, a method of preparing the same, and a rechargeable lithium battery including the same.

Negative active material for rechargeable lithium battery, method of preparing the same, and rechargeable lithium battery including the same

A lithium ion battery electrode includes silicon nanowires used for insertion of lithium ions and including a conductivity enhancement, the nanowires growth-rooted to the conductive substrate.

Electrode including nanostructures for rechargeable cells

Provided are electrode assemblies that contain electrochemically active materials for use in batteries, such as lithium ion batteries. Provided also are methods for fabricating these assemblies. In certain embodiments, fabrication involves one or more electrospinning operations such as, for example, electrospinning to deposit a layer of fibers on a conductive substrate. These fibers may include one or more electrochemically active materials. In the same or other embodiments, these or similar fibers can serve as templates for depositing one or more electrochemically active materials. Some examples of active materials include silicon, tin, and/or germanium. Also provided are electrode fibers that include cores containing a first active material and shells or optionally second shells (surrounding inner shells) containing a second active material. The second active material is electrochemically opposite to the first active material. One or more shells can function as a separator and/or as an electrolyte.

Electrospinning to fabricate battery electrodes

Provided are conductive substrates having open structures and fractional void volumes of at least about 25% or, more specifically, or at least about 50% for use in lithium ion batteries. Nanostructured active materials are deposited over such substrates to form battery electrodes. The fractional void volume may help to accommodate swelling of some active materials during cycling. In certain embodiments, overall outer dimensions of the electrode remain substantially the same during cycling, while internal open spaces of the conductive substrate provide space for any volumetric changes in the nanostructured active materials. In specific embodiments, a nanoscale layer of silicon is deposited over a metallic mesh to form a negative electrode. In another embodiment, a conductive substrate is a perforated sheet with multiple openings, such that a nanostructured active material is deposited into the openings but not on the external surfaces of the sheet.

Open structures in substrates for electrodes

Provided are novel negative electrodes for use in lithium ion cells. The negative electrodes include one or more high capacity active materials, such as silicon, tin, and germanium, and a lithium containing material prior to the first cycle of the cell. In other words, the cells are fabricated with some, but not all, lithium present on the negative electrode. This additional lithium may be used to mitigate lithium losses, for example, due to Solid Electrolyte Interphase (SEI) layer formation, to maintain the negative electrode in a partially charged state at the end of the cell discharge cycle, and other reasons. In certain embodiments, a negative electrode includes between about 5% and 25% of lithium based on a theoretical capacity of the negative active material. In the same or other embodiments, a total amount of lithium available in the cell exceeds the theoretical capacity of the negative electrode active material.

Preloading lithium ion cell components with lithium

Provided are novel electrodes for use in lithium ion batteries. An electrode includes one or more intermediate layers positioned between a substrate and an electrochemically active material. Intermediate layers may be made from chromium, titanium, tantalum, tungsten, nickel, molybdenum, lithium, as well as other materials and their combinations. An intermediate layer may protect the substrate, help to redistribute catalyst during deposition of the electrochemically active material, improve adhesion between the active material and substrate, and other purposes. In certain embodiments, an active material includes one or more high capacity active materials, such as silicon, tin, and germanium. These materials tend to swell during cycling and may loose mechanical and/or electrical connection to the substrate. A flexible intermediate layer may compensate for swelling and provide a robust adhesion interface. Provided also are novel methods of fabricating electrodes containing one or more intermediate layers.

Mark C. Platshon

Papers

Electrode including nanostructures for rechargeable cells

Electrospinning to fabricate battery electrodes

Open structures in substrates for electrodes

Preloading lithium ion cell components with lithium

Intermediate layers for electrode fabrication